EPS C20 Final Study Guide
Loma Prieta: Cypress Viaduct
- Collapse: Section on landfill over soft mud - No collapse: Section on stronger sand and gravel - Most shaking in soft mud
Francis Bacon (1620)
- Discovered that Africa and S. America's coastal outline fit together like a puzzle - "Not an accidental coincidence"
Ocean Transforms
- Displacement side by side (refer to drawing in notebook) - Can move left or right lateral
Bulnay Fault, Mongolia (1905)
- M 8.1 - Penultimate rupture - Largest magnitude in shallow continental crust - Use repeated displacement to see future slips - ~3 ka
Rat's Island, Alaska Earthquake
- M 8.7 - 8th largest earthquake - Didn't produce a large tsunami bc they're so far away
Tohoku Earthquake (2011)
- M 9.1 - Around 300k people exposed - 16k people dead in tsunami - Around 5% people in inundated areas
Sumatra Earthquake (2004)
- M 9.1 - Around 300k people exposed - 230k people dead in tsunami
Sumatra-Andaman Earthquake (2004)
- M 9.2 - 1200 km rupture - 2nd largest earthquake - Earthquake not felt in California, but CA seismographs measured displacement.
Why is earthquake prediction like the analogy of an avalanche on a pile of sand?
- No way of predicting how system works like earthquakes - Don't know when sand will topple
Faults and their Equivalents
- Normal = Divergent boundaries (tension) - Reverse = Convergent boundaries (compression) - Strike slip = Transform boundaries (shear)
Mid Ocean Ridge
- Normal fault (tension) - Divergent boundary - We know strike but not dip. (see notebook for diagram).
The Largest Plates
- North American - Eurasian - Pacific - Antarctic - South American - African - Australian
Body Wave Magnitude
- Notation: Mb - Measured from P wave amplitude of distant earthquake
Codd or Duration Magnitude
- Notation: Mc - For smaller earthquakes
Local Magnitude
- Notation: Ml - For smaller areas - For local earthquakes - Similar to Richter magnitude
Surface Wave Magnitude
- Notation: Ms - Measured from amplitude of surface waves of distant earthquake
Moment Magnitude Scale
- Notation: Mw - A logarithmic scale that directly measures earthquakes by estimating the total energy released by an earthquake - Most commonly used and preferred scale today
Examples of Seismic Risks
- Population density and exposure - Construction quality of buildings and structure - Personal preparedness
Richter's Claims on Intensity
- Varies spatially for a given earthquake - Subjective measure (depends on type of building) - Need a measure of "size" of earthquake
Example of Strike Slip Faults
- Wallace Creek - San Andreas - Carrizo Plain, CA
Rapid Magnitude Estimation
- Warning system uses frequency of p-wave arrival to determine earthquake magnitude - Earthquake mitigation efforts in the US use long timer probabilistic hazard assessments and post earthquake notification to reduce damage of earthquake
Lesson Eight from Research: Risk and Communication
Scientists struggle to communicate bc science is a culture. There's unique language, terms, and concepts. There are specific channels used that are only accessed by scientists (conferences, journal articles). This can create isolation. Language used to impress colleagues rather than interacting w/ people.
What amplifies strength of a wave?
Sea bin (ex. Thailand in Sumatra earthquake)
How many times did plate separation occur in Earth history?
4-5 times (separate, come back, separate, collide, separate)
How old is the Earth
4.6 billion years old (4.5 mentioned in lecture)
The Bay Area moves at...
40 mm/year
What is the probability of rupture of Southern Hayward Fault over the next 30 years
40-75%
How many decimal places are needed for accuracy (latitude and longitude)?
5
What is the delay goal for earthquake early warning system?
5 seconds
Pacific North American Boundary Slip Rate
50 mm/year
How much has 50 year flood flows increased in Southern Sierra?
50-100%
1964 Alaska Earthquake: Wave Height
6.1 meters
What was the maximum displacement during 1906 earthquake in San Francisco?
6.5 meters
What was the average delay for seismic stations to process information?
6.5 seconds
What is the probability of an M > 6.7 earthquake by 2032 (in California)?
62%
Rate of Seismicity in SF Region
63% chance of M ≥ 6.7
Rate of Seismicity on LA Region
67% chance of M ≥ 6.7
What is a volcano considered during a convergence?
Secondary effect
How many fires would result from the Haywired scenario and what are the damages?
670 fires damaging ~53k houses (aggravated by water supply damage)
What does green circles mean on the Google Earth file?
70-150 km
What deep are the deepest earthquakes?
700 km
The Great San Francisco Earthquake (1868) is the ___ most deadly Calfornia earthquake.
7th
How deep is the Juan de Fuca Ridge?
80 km
What is the probability of an earthquake between M6 - M 6.6 by 2032 (in California)?
80%
How old is communication as a research discipline?
80+ years old
Where do most fatalities from earthquakes occur (California)?
84% of fatalities in California occur in San Francisco and Oakland.
How many residents would need shelter after SAFRR earthquake scenario?
8500
How many M≥3 earthquakes occurred during 1973-2008 in Central U.S.?
852 (more scattered across U.S.)
How many M≥3 earthquakes occurred during 1973-2008?
867
How many pipelines accomodate 10% of U.S. crude storage and cross cushing?
9 major pipelines
What is the value of 1 g?
9.81 m/s^2
Rate of Seismicity Statewide
99% chance of M ≥ 6.7
Loma Prieta Falling Hazards Rate
> 50% injuries linked to falls
The Goal of Data Latency and Network Status
> 90% stations operation - Data latency < 1 seconds
Modified Mercalli Intensity Scale
A 12 point subjective scale developed to evaluate earthquake intensity based on the amount of damage to various structures
How does a bomb create seismic energy?
A bomb creates seismic energy in the form of compressional P waves similar to sound waves in all directions away from point source.
Partitioned Slip
A combo of strike slip fault and dip slip fault (normal fault)
Seismograph
A device that records ground movements caused by seismic waves as they move through Earth
Earthquake Warning Times in San Francisco
A few seconds to tens of seconds
Tsunami
A giant wave generated by any process that produces uplift or subsidence of sea floor
What can aftershocks also lead to?
A larger main shock
Magnitude
A measure of energy released in earthquake
Seismic Moment
A measure of the energy released in an earthquake obtained by fitting long period seismic waves
Example of Background Earthquakes
A moderate earthquake on the Hayward fault will redistribute some of the constraints that are applied on the San Andreas fault, but will not necessarily be taken into account in the models that are used.
Fire
A secondary hazard we need to worry about
Example of a Love Wave
A shear wave tied to surface
Foreshock
A small earthquake that often precedes a major earthquake
What does a great amount of displacement on fault mean?
A sum of many movement recurrent on same fracture by renewal of elastic strain
Convergent Plate Boundary
A tectonic plate boundary where two plates collide, come together, or crash into each other.
What are common at hotspots?
A volcanic island at the end of a chain of islands (not a subduction)
What did the Indian Ocean lack (NOVA)?
A warning signal
When did the largest earthquake happen (Rocky Mountain Arsenal)?
A year after injection stopped (M 4.9)
Hanging Wall
Above fault
Where is the epicenter located?
Above the hypocenter
Where do earthquakes grow?
Across a rupture area on the fault surface
The tsunami in Japan (2011) propogated ____.
Across the Pacific
Lesson Two from Research: Risk and Communication
Seeing the public as one massive group is wrong. Find channels that appeal to different audiences.
_______ and ______ are used to calculate _________ from a single fault or an ensemble of faults for building codes and critical facilities.
Magnitude; recurrence; ground motions
Why is it difficult to divide fault into fault segments based on their likeliness of hosting earthquakes of different sizes
Segments aren't set in stone.
Earthquake clusters challenge our ability to...
Predict probability of future earthquakes
_____ isn't possible, but _____ is the answer.
Prediction; mitigation
Step 3: Prepare Disaster Kits (7 Steps to Earthquake Safety)
Prepare: - Household disaster kit - Personal go kits
Downtime of Collapse Prevention: Performance Level
Probable total loss
Alfred Wegener (1880-1930)
Proposed idea of continental drift
How does social distancing impact seismic activity?
Seismic noise has gone down due to decreased human activity from social distancing.
What type of observations are available in Japan and around the world?
Seismic observations
Seismic Velocity vs. Depth of the Earth
Seismic velocity gets faster deeper down.
What do you use to image the Earth?
Seismic wave velocities
What type waves the earthquakes produce?
Seismic waves and energy that propagate Earth in some velocity
A fault that goes left and right is...
Right lateral
Plate Tectonics
Rigid plates moving across the surface of the Earth
When the plates are ____, the deformation occurs ____.
Rigid; at the edges
Where are the 20 biggest earthquakes located?
Ring of Fire (subduction zones around Pacific Plate and Indian plate)
What do people falsely claim about earthquakes?
Rise in earthquakes is due to global rise.
What happens to transportation after the Shakeout Scenario?
Roads impassable due to damage, debris, landslides, fault rupture, gridlock, stranded commuters
Rocks vs. Velocities vs. Earth's Depth
Rocks get more rigid and velocities get faster as we go deeper into the Earth through the crust, lithosphere, and mantle.
What are the continents made out of?
Rocks that aren't very dense (less dense than ocean crust)
What does surface rupture recognize?
Rupture geomorphology and structure that can be seen while fresh
Energy radiates from _____ as _____.
Rupture surface; seismic waves
Earthquakes occur in a ____ area on which ___ occurs.
Rupture; slip
Where did the 1906 San Francisco Earthquake M 7.8 rupture?
Ruptured from San Juan Bautista to Cape Mendocino
What is the goal for reproductivity during a pandemic?
Rₒ < 1
Shear Wave
S wave
What is a direct measure of distance?
S-P time
What bridge collapsed during the Loma Prieta Earthquake (1989)?
SF-Oakland Bay Bridge
Aristotle (384-322 BCE)
Said earthquakes were caused by strong winds that blew through caves inside earth (similar to winds in our bodies that cause throbbing)
Lucretius (99-55 BC) and Seneca (4 BC- 65 AD)
Said earthquakes were caused by underground rock falls
If LA goes offshore, what would it be moved by?
San Andreas Fault
What is an example of a transform fault that humans live on?
San Andreas Fault
Shakeout
San Andreas Fault Southern California earthquake scenario (2008)
What city did the 1868 Hayward Earthquake hit besides Hayward?
San Francisco
What is the most active area in East Bay in terms of seismicity?
San Ramon
SAFRR
Science Application for Risk Reduction
Disciplines Brought Together by Preparedness Campaigns
Science ➝ preparedness campaigns ➝ communication + emergency management
Why Predicting Earthquakes is So Hard
Scientific processes are difficult. 1. Observation and measurement of physical process 2. Development of physical theory to predict outcome
What are the flaws behind science communication?
Scientists offer too many details, which can lead to miscommunication to the media and general public.
What do you need to know to measure change in velocity of an earthquake?
The exact location of an earthquake
Uniform Building Code (1928)
The first one established that included recommendation for earthquake resistant forces
What did scientists do when studying Bay Area's earthquake history (1600-Present)?
They tend to divide fault into fault segments based on their likeliness of hosting earthquakes of different sizes?
How are pandemics like earthquakes?
They're at constant risk.
Why are earthquake precursors hard to pinpoint?
They're scientifically very stringent and challenging requirements.
How is is Berkeley extending coverage?
They are expanding network with 85 stations today.
How have messages about earthquake safety improved?
They became more inclusive.
Why are wood beams ductile?
They can bend and absorb earthquake motion w/out breaking.
Wind Waves
They come and go without flooding higher areas.
Why are masonry bricks and mortar are brittle?
They crack and collapse.
How are waves generated?
They get generated at rupture plane (where slip propagates on fault). Different types of waves are initiated.
Why don't disciplines sometime don't get along in theory?
They have different pools of thought.
What is true about different waves?
They have different velocities and particle motions .
What is true about bigger earthquakes?
They have stronger shaking and shake large areas.
What was wrong with past preparedness campaigns?
They inaccurately communicated risk and created skepticism in public.
How did Japan's earthquake early warning system deal with the 2011 Tohoku earthquake?
Underestimated its magnitude of 9.0
Knowing intensities of small and large earthquakes help us...
Understand shaking distribution of an earthquake
What is big takeaway from David Schwartz' guest lecture?
Understanding how faults work and good engineering can serve us well for preparing for earthquakes.
Earthquakes are ___.
Unpredictable
Y-axis
Up and down
What are the first motions of a P wave from a fault?
Up or down
Age of Continents
Up to 4 billion years old
Japan (Convergent Plate Boundary)
Upper plate mostly oceanic ging underneath volcanoes - Can also go underneath oceanic crust
Dr. David Steward
Urged public to keep open mind on predicting earthquakes
What should you do if you suspect a gas leak?
Use manual gas shut off
The Original Seismograph
Use mass and Earth moves around it. Pen attached to mass makes seismograph.
How did we develop seismic hazard maps?
Used knowledge of plate tectonic and history of earthquakes in the past across (and size of earthquakes)
Nonogram
Used to estimate magnitude before computers by calibrating it relative to the amount of shaking of that particular instrument
Seismic Tomography
Uses seismic waves collected from seismic stations to create an x-ray of Earth's interior
How are earthquakes located?
Using P and S wave arrival times at many seismic sensors
Ingredient 2
Vague prediction of earthquake
Relationship Between Velocity and Rock Types
Velocity is faster as you go deeper into the Earth (as rocks are more dense/rigid).
Z-axis
Vertical
Which component is the most sensitive in the P wave?
Vertical component (z axis)
What type of force do building design mostly focus on?
Vertical forces
Red (ShakeMap)
Very extreme
What type of rocks transmit energy better than chewed up rocks in fault zones?
Very solid granites
Estimates of when the next earthquake will occur are _____.
Very uncertain
Hot Spots
Volcanic regions fed by underlying mantle (refer to diagram in notebook)
What does reproductivity (Rₒ) measure?
Vulnerability or the # of people who will get infected by the virus Ex. If Rₒ = 2, a person will infect 2 other people.
Example of Vulnerability (Sun Scenario)
Vulnerability to sunburn depends on: - How strong the sun is - How long you sit in the sun - How sensitive your skin is
____ is most likely to induce earthquakes.
Wastewater disposal
-nami
Wave
Example of a Rayleigh Wave
Waves on lake surface
What happens during a tsunami?
Waves propagate very fast, but waves are gentle (around 500 mph).
What is the benefit of having enough seismic stations and earthquakes propagating their waves toward the stations?
We can figure out which areas seem to have lower seismic velocity.
Shaking vs. Earthquake
We can predict shaking, but NOT earthquake.
What's the benefit of having large earthquakes?
We can provide increase hazard probabilities.
Why can't we do better than a statistical model when creating a physical model to forecast seismicity?
We don't know where every fault is located.
Takeaway from Iben Browning's theories?
We need theoretical basis for predictions before we believe them.
Blue (ShakeMap)
Weak
Which part of the U.S. is at the greatest risk?
West Coast
Long Term Slip Rate (Hayward Fault)
~10 mm/year
How often do the volcanoes on Cascadia Mountain Range erupt?
~100 years
What do beach ball diagrams show?
- 2 orientations a fault can have - Geometry of fault
Earthquakes on East vs. West Coast
- 2014 Napa Earthquake M 6.0 - 2011 Mineral, VA Earthquake M 5.8
Azle, Texas (November 2013-January 2014)
- 27 M2+ earthquakes - Didn't have seismometer - Used USGS seismic sensor
2014 Case Study by USGS (New Madrid Seismic Zone)
- 3 quakes M 7.8+ in 1811 and 1812 - Peak ground acceleration w/ 2% probability of exceedance in 50 years
Mexico City
- 300k from subduction zone - Sits on sedimentary basin - Built on lake bed
West Central Denali Paleo-Offsets
- 50 km west of 2002 epicenter 8m in 2 events - 8m offset (~2 similar earthquakes caused this) - Had smaller offsets (series of 4m offsets)
What did Dr. Iben Browning predict?
- 50% chance of M > 6 earthquake within 5 days around December 3, 1990 - Shows magnitude, location, time period
Scenario Earthquake: Bay Area
- 7 faults - 18 fault segments - 35 rupture scenarios Note: Each of these must have a probability and each possible earthquake must be identified.
Shakeout Scenario of Los Angeles
- 7.8M earthquake - 1800 deaths - $213 billion in economic losses
Juan de Fuca Cascadia Initiative (2010-2014)
- 70 ocean bottom seismometers - Deployed each year for 4 years - 280 deployment locations
Results of Haywired Scenario
- 800 deaths - 1800 nonfatal injuries from building and structural damage (caused by shaking and liquefaction) - 2500+ people in region could require rescue from collapsed building - 22k+ people could require rescue from stalled elevator - 52k+ single family homes could burn as a result of more fires than can be fought by available firefighters and firetruck
Earthquake Death Toll from Last Century
- > 2 million total
Northridge Falling Hazards Rate
- > 50% injuries from non-structural (falling) hazards - $2-3 billion cost of injuries
Dr. Iben Browning
- A meteorologist - Predicted Loma Prieta earthquake (no documentation
Love Wave
- Side to side particle motion in horizontal plane - A surface wave
Downtime of Damage Control: Performance Level
2 to 3 weeks
How much does North America move away from Europe?
2-3 cm/year or 1 inch/year
2011 Japan Earthquake: Wave Height
2.4 meters
When did plate tectonics begin?
2.5 billion years ago
How many seconds of warning did Loma Prieta receive?
20 seconds for San Francisco and Oakland
Hayward faults accounts for _____ of total plate motion.
20%
Death Toll of 2010 Puerto Rico Earthquake
200,000
Bay Area Earthquake Probabilities
2000-2030: 70% 2003-2032: 62% 2007-2036: 63%
When did the next Parkfield earthquake ACTUALLY occur?
2004
Where have we seen the prevention of column failure?
2014 Napa earthquake bc there was minor damage
What is an example of an explosive source that created seismic energy?
2017 North Korean nuclear test
S-P Time for Ridgecrest Earthquake
21 seconds
How many satellites are continually orbiting earth?
24
Downtime of Immediate Occupancy: Performance Level
24 hours
How long did it take to fix the SF-Oakland Bay bridge after Loma Prieta Earthquake?
24 years
About how many big earthquakes occur in CA, Hawaii, U.S. Virgin Islands, and Puerto Rico respectively?
250+
What do the 3 components on MyShake represent?
3 directions of movement
How is the distance of waves measured?
As an angle in degrees (from pole to equator)
____ frequency waves lose energy more quickly than _____ frequency waves.
High; low
Low Frequency
Higher
The ____ the injection rate, the ____ the likelihood of earthquake.
Higher; higher
What does pink mean on an earthquake probability map?
Highest probability of shaking
What do creeping faults do?
Release plate tectonic strains w/out need for earthquakes
What do locked faults only do?
Release strain in earthquakes
What is observed along faults?
Repeating earthquake cycles
Riley Act
Required earthquake resistant standards and inspections for all buildings
What does the GPS let us see?
The elastic loading of individual faults.
Plates change velocities frequently. (T/F)
True
Performance Levels
- Collapse prevention - Life safety - Damage control - Immediate occupancy
What does the SAFRR Project integrates?
- USGS earth science research - Social science - Needs of external partners
Predicting earthquakes is like finding the theory behind Newton's Apple. (T/F)
True
Protect yourself first in a disaster before helping others. (T/F)
True
Seismic data is openly available for research. (T/F)
True
Some earthquake cycles are regular or irregular. (T/F)
True
Some earthquakes occur far away from actual plate. (T/F)
True
Stress shadows affect other faults. (T/F)
True
Subducting zones can have some fault creeps. (T/F)
True
The 1st disaster dissertation was observational. (T/F)
True
The Indian Plate's movement is a rare case where plate changed velocity over time. (T/F)
True
The Pacific Northwest is prone to earthquakes. (T/F)
True
The common and scientific answers for defining an earthquake are BOTH correct.
True
The further the lines are on a beach ball diagram. the shallower the dip. (T/F)
True
There are roughly 10x as many M4 earthquakes as there are M5 earthquakes. (T/F)
True
There are ~ten times as many M4 as there are M5 earthquakes. (T/F)
True
There has been no clear evidence or documentation of electrical conductivity. (T/F)
True
There have been no convincing observations of changes in velocity prior to earthquakes. (T/F)
True
There used to be a subduction zone in the Bay Area, but the two plates connected over time. (T/F)
True
Tsunamis in oceans are undetectable. (T/F)
True
Tsunamis run quickly over lands as wall of water. (T/F)
True
Using more data is better. (T/F)
True
Visitors are not typically well educated about tsunamis. (T/F)
True
Waves propagate in every direction. (T/F)
True
Some sequences continue long after injection stops. (T/F)
True (ex. Rocky Mountain Arsenal)
Tsunami Scenario
Tsunami generated by an Alaskan earthquake and impacting the U.S. West Coast (2013)
What is the early origin of earthquakes for Native Americans?
Turtles waking up
Each type of magnitude scale is ____ to they're similar to the ___ as possible.
Tweaked; Richter magnitude scale
What was the displacement across San Andreas in 50 years prior to the 1906 earthquake?
3.2 meters
Who created the building rating system?
U.S. Resiliency Council
Which region had the most tsunami victims (Sumatra earthquake)?
3/4 of tsunami victims died in Sumatra.
We have to assign ____ to forecasts.
Uncertainties
Death Toll of 1868 Hayward Earthquake
30 deaths, 5 in SF
How much has 50 year flood flows increased in Northern Sierra?
30-90%
At what temperature will rocks flow?
300-600 degrees
What do blue and red circles mean on the Google Earth file?
300-700 km
Age of Channel (Hayward Fault)
32,000 years
Each magnitude difference is a factor of...
32x energy
How long is the creek offset between Strawberry Creek?
335 m
How many M≥3 earthquakes occurred during 2009-2019?
3642
How many M≥3 earthquakes occurred during 2009-2020 in Central U.S.?
3665 (more concentrated in specific zones)
Memorial Stadium is creeping at _____.
4 mm/year
Do we want earthquake predictions?
Under strict conditions
The Number of Earthquakes to Offset Strawberry Creek
~170
Slip Length from Hayward Earthquake
~2 m
Spatial Correlation: Characteristics of Induced Earthquakes
Are earthquakes close to mining/oil and gas operations?
How many earthquakes per year occurred in Central U.S. during 1973-2008?
~24
How many earthquakes per year occurred in Central U.S. during 2009-2020?
~330
Where does most surface deformation occur?
At the 3 types of plate boundaries (divergent, convergent, transform)
Dual-Use Networks
Early warning + research into next generation hazard reduction
Oklahoma vs. California in 2014-2017
Earthquake rate in Oklahoma is greater than California's earthquake rate.
What happened in Central U.S. in 2015?
Earthquake rate peaked, but is still declining due to reduced human activity.
What happened in L'Aquila, Italy?
Earthquake struck anyway (M 6.3).
MyShake and MyQuake
Earthquake tracker apps developed by UC Berkeley Seismology Lab
What is the source of the biggest tsunamis?
Earthquakes
Why was the trial in Italy regarding Members of Council controversial?
Earthquakes aren't predictable.
Why do vulnerabilities matter in the context of earthquakes?
Earthquakes don't kill people, buildings do.
Background Earthquakes
Earthquakes that occur on the same fault system but are not necessarily included in the models used for forecasting earthquakes
Gap Filling Earthquakes
Earthquakes that occurred in areas that haven't had earthquake in a long time
What is the relationship between early origins of earthquakes and animals?
Earthquakes were associated with giant creatures that supported the earth.
"____ don't kill people, ____ do."
Earthquakes; buildings
At which fault did the Turkey earthquake occur in?
East Anatolian fault
What is the Southern Anatolian plate also called>
Eastern Anatolian Fault
Tsunami Scenario Uniqueness
Highlights impact to ports, port traffic, and world's 8th largest economy (CA)
Wegener's ideas were discussed for a decade. However, what happened next?
His ideas were dropped by the scientific community.
East Bay Seismicity (1984-2002)
Historical earthquakes have been M ≥ 5. - M 5.5 (1954) - M 5.7, 5.8 (1980) - M6 (1861) - M 5.7 (1986)
Oklahoma
Home of Quakenado
What component is in the S wave?
Horizontal component (x and y axis)
Volcanoes ____ from the hotspot are ____.
Farther away; older
Why was there variable behavior on Hayward fault after the 2014 South Napa earthquake?
Fault eventually moved half a meter.
Blind Thrust Fault
Faults that don't appear at the surface
Lesson Five from Research: Risk and Communication
Fear campaigns are rarely successful. Think short term gains w/out positive suggestions on ways to improve circumstances. These campaigns are largely ignored anger from the publics towards the fear inducing agency.
What type of force do earthquakes cause?
Horizontal forces
Bert the Turtle (1950s)
"Cartoon Character" that gave kids a sense of safety about being hit with a nuclear bomb
What is the cost of retrofit post earthquake repair?
$100000-$40000
Building Damage in 1989 Loma Prieta
$12 billion
What is the cost of retrofit now?
$2000-$10000
How big are the losses of boats and docks from the tsunami scenario?
$700 million
What is the reproductivity (Rₒ) during a pandemic?
(Duration) x (opportunity) x (transmissibility) x (susceptibility)
Reduced Risk: Denali Earthquake
(Hazard) x (vulnerability)
What is the risk during a pandemic?
(Hazard) x (vulnerability)
Seismic Risk
(Seismic hazard) x (vulnerability)
Strike Slip Nodal Plane Diagram
(see diagram)
Pull vs. Push Diagram
(see notebook under midterm 2 review section)
Right Lateral vs. Left Lateral Diagram
(see notebook)
Seismic Wave Visual
(see notebook)
Source Mechanism Diagram
(see notebook)
What factors determine an earthquake scenario?
- # of faults - # of fault segments - # rupture scenarios
Annualized Loss in CA (Total Long Term Expected Average per Year)
- $2.2 billion average annual loss (building damage) - $104 average annual loss per capita (building damage)
What are the losses if the 1906 SF earthquake (M 7.9) occurs again?
- $4 billion damage (buildings only) - $170-$225 billion damage (all losses)
Breakdown of Economic Loss: Shakeout Scenario of Los Angeles
- $48 billion from shaking damage - $65 billion due to fire - $96 billion due to business interruption - $4 billion due to traffic delays
Statewide Loss from Tsunami
- $5-10 billion - Exact cost depends on action and prep - Recovery depends on planning
How much is the annualized earthquake loss?
- $6.1 billion per year - 61% in California - 73% CA + OR + WA
Calculating Earthquake Slip Accumulation Rate
- (Long term - creep rate) x (time) - ex. (10 mm/year - 0.0 mm/year) x (2020-1868) = 1.5 meters
How many people live/are in the inundation zones and would need to evacuate from the tsunami?
- 1/4 of million people living in areas - 1.4 of a million tourists and visitors on coast
North Coast Vedanta Site
- 12 events within the last 2566 years (average interval of 233-263 years) - 5 events within last 810 years (average interval of 167-192 years)
The Shakeout Scenario
- 180-mile rupture - M 7.8 - 100 seconds of fault rupture - Shaking for 2+ minutes in many places
Japan: Earthquake Early Warning Systems
- 1800 seismic stations installed after Kobe earthquake - 2004: JMA begins testing - 2005: Successful warning in Sendai, Miyagi that alerted 140 schools and agencies (M 7.2) - 2007: Nationwide public warning system launched
How big is the population of the Bay Area in 1868 vs present day?
- 1868: ~260,000 - Present: ~8 million (30 times larger)
Studying Induced Earthquakes
- 1908 Bochum Seismological Laboratory - 1920 Silesia Coal Basin Seismic Monitoring
Where was the problem of non-ductile concrete buildings recognized?
- 1985 Mexico City earthquake - 1994 Northridge earthquake - 1995 Kobe earthquake - 2011 Christchurch earthquake
Where was the problem of soft-story buildings recognized?
- 1989 Loma Prieta earthquake - 1994 Northridge earthquake
Where was the problem of single family homes (observed building failure modes) recognized?
- 1989 Loma Prieta earthquake - 1995 Northridge earthquake - 1993 Long Beach earthquake - 2011 South Napa Earthquake
Rocky Mountain Arsenal (Denver)
- 1st observation of injection-induced earthquakes - Fluid injection begins in 1962 - Earthquakes began shortly after injection - Where chemical weapons are created
Lake Mead (1935)
- A reservoir that experienced M~3 earthquakes caused by filling of reservoir - Water infiltrated faults below reservoir, causing slip on fault
Statement from the Road
- A short media story written in POV of the organization - Still used today
Richter's Claim on Magnitude
- A single number for an earthquake - Initially, a measure of amplitude of ground - Shaking w/ respect to a reference point
Column Failure
- A steel and concrete based structure that's vulnerable - Most traumatic and costly damage
Byerly Vault
- Above UC Berkeley campus - One of the original WWSSN networks
How does the USGS spread awareness of the tsunami scenario?
- Ads - Brochures - Media
Yellowstone Caldera
- Age progressive rack - High gravity anomaly - High helium ratio - Responsible for some of biggest volcanic eruptions in U.S. (but they're rare)
Lessons From Mexico and Japan
- Alert message must be simple and provide action - Alert delivery must be geo-targeted (to those who need it)
Consider: Will you have medical services? (Earthquake Preparedness)
- All emergency systems may be overloaded. - Hospitals and other medical facilities may be damaged. - Emergency rooms and trauma centers may be overwhelmed. - Assisted living, critical care, and other health services (ex. dialysis) may not be operational.
Benefits of GPS in Plate Tectonics
- Allows determination of motions of globally distributed points at mm/year precision
The Great Shakeout Earthquake Drill
- An exercise developed as an outcome of the Shakeout scenario - A public drill - Promoted by schools, businesses, and community organizations
Silver Bullet
- An observable that we can make before every earthquake - Tells us information about large earthquakes
Faults
- Any fracture in Earth separating 2 pieces of rock sliding against each other so each individual fault can slip and make earthquake - Can occur within a plate boundary - Fracture in rock with movement across from it - Plate boundary itself is a fault
The Palmdale Bulge
- Apparent rapid uplift in region starting in 1960s - Maximum of 35 cm - No earthquake occurred - Signal turned out to be data error - Bulge diminished
Relationship between Turkey and Plate Tectonics
- Arabian plate thrusting into Iran (lot of deformation) - Arabian plate squeezing Turkey and Anatolian plate to West - Left later (moving North at 2-3 cm per year)
Near Surface (Shallow Depth): Characteristics of Induced Earthquakes
- Are earthquakes close to surface (since human activity is close to surface)? - Earthquakes near surface more likely to be induced.
Samoa Tsunami (2009)
- Around 185 people died - M 8.2 offshore Samoa - 10-20 minutes to evacuate (not enough time) - Highest recorded wave height: 35 feet
Rate of Plate Tectonics
- As fast as a growing finger nail (mm/year to 10s of cm/year) - A foot per year in some places
How powerful was the North Korean nuclear explosion?
- As strong as two earthquakes (M 5.2 and M 4.4) - Had explosion and implosion sequence - 3x bigger Hiroshima
In what scenarios do we not feel earthquakes?
- Aseismatic creeping fault - Locked faults
ARKStorm
- Atmospheric River (AR) 1000(K) Storm - Winter storm scenario impacting U.S. West Coast (2010)
What to Expect After Next Quake (Observed Building Failure Modes): Non-ductile concrete buildings (Pre-1976)
- Collapse - Partial collapse - Debris on street
Why should you prepare disaster kits?
- Basic services (electrical, water, gas, etc) may be disrupted for several days - Emergency responders will be overwhelmed - Your house needs to be self sufficient for at least 3-5 days
Example of Past Preparedness Campaigns
- Bert the Turtle (1950s) - Hydrogen Bomb Campaign
Caribbean Plate
- Between North and South American plate - Small plate - Has 2 subduction sones - Has transform boundaries on North and South
Prince William Sound, Alaska Earthquake (1964)
- Biggest historic American earthquake - Happened in Anchorage along subduction plate boundary of Pacific Plate pushing underneath Alaska - Biggest damage from liquefaction bc ground wasn't bedrock - Tsunami produced by sea floor deflection in earthquake - Had wide zone of subsidence and uplift - Produced damage in Crescent City, Northern CA
SAFRR Tsunami Scenario: Results
- Billions of dollars in losses in CA - Largest economic impact in CA - 1/3 boats damaged - 2/3 docks damaged or destroyed
What resources are found in mid-oceanic ridges?
- Black smokers producing rich mineral deposits at 2.5 km depth - Black water heated by magma - Wildlife - Energy in Earth's interior
Retrofit
- Bold building to foundation - Build shear walls - Add metal frames - No laws requiring retrofit, even on sale of homes
Dealing w/ Water and Gas Pipes: Step 1 of 7 Steps to Earthquake Preparedness
- Brace water heaters and other gas appliances - Replace rigid gas connections to water heaters and other gas appliances w/ flexible (corrugated) stainless-steel gas connectors
Latest Events Involving Plate Tectonics
- Break-up of Pangea - North America and Europe 1) split apart from each other for thousands of kilometers 2) subduction formed 3) moved towards each other again 4) collided in continental collision; split up
Brittle Deformation
- Brittle materials change a little and then break suddenly - Fractures rock
Earth Tides: Iben Browning's Theory
- Bulge of water due to gravitational attraction of the moon - Solid earth also bulges, creating earth tide and applying stress on faults - If all planets pull in same direction as the moon, that produce stresses that would produce large earthquake. - Moon is more important than other planets because it's smaller/closer.
How has changes in solid stress due to fluid extraction or injection caused earthquakes?
- By adding or removing fluid, you change the amount the fault is being pressed down upon. - Poro-thermoelastic effects, changes in gravitational loading.
How to reduce embarrassment when executing public education about earthquakes?
- Can be addressed by humor, visual aid, messaging - More frequent drills - Normalizing behavior
How do earthquakes interact with each other?
- Can enhance the occurrence of other earthquakes in the vicinity - Can produce stress and temporarily decrease the number of earthquakes in the area
Limited Water Supply: Shakeout Scenario of Los Angeles
- Can last for a year - 88% of water comes from outside the region - Much of water crossed fualt lines, travels in very old pipes
Juan de Fuca Subduction
- Caused by compression and convergence - Moves 4 cm/year
Reverse and Thrust Fault
- Caused by compressional tectonic environments - Strike and dip - Has dip slip - Hanging wall goes up, foot wall goes down [see notes for beachball diagram]
Strike Slip Fault
- Caused by translational tectonic movements - Goes in 2 directions - Strike and dip - Has dip slip - Motion across fault is horizontal - No hanging/foot wall [see notes for beachball diagram]
What does GPS measure?
- Changes in position - Displacement of Earth's surface
What affects velocities and refract seismic waves?
- Changes in temperature - Rock types
Step 6: Check for Injuries and Damages After Quake (7 Steps to Earthquake Safety)
- Check yourself for injuries and then help others. - Protect mouth and nose from dust - direct pressure to bleeds - Don't move someone who is severely injured unless they're in danger - Cover injured people w/ blankets (to help w/ shock)
Rayleigh Wave
- Circular particle motion in vertical plane - A surface wave - The deeper you go, the lesser the motion gets
Fault Segment
- Clusters of earthquakes - Section of faults believed to slip in single, large earthquake
Earthquake Cluster
- Clusters of earthquakes in time (where there are many earthquakes in time than at other times) - On individual and groups of faults
Why was Wegener's idea of continental drift dropped?
- Coastlines don't match perfectly (could be coincidence) - Were rock formations really the same? - Impossible to have continent plow through rocks
What to Expect After Next Quake (Observed Building Failure Modes): Unreinforced Masonry Buildings
- Collapse - Fallen walls - Bricks falling into street
Non-ductile Concrete Buildings
- Collapses in moderate earthquake - Brittle behavior in joints and columns - Limited reinforcing steel - Affects buildings constructed prior to late 1970s when 1976 code was adopted
What is Chris Goldfinger known for?
- Collecting sediment up and down coast - Drilling into the sediment and carbon dating the sediment
What is responsible for increased earthquake activity?
- Combination of volcano and active faulting - Hotspot deforming crust
How was the Lawson Report created?
- Compiled newspaper reports - Cataloged/recorded damages
Transamerica Building
- Completed in 1972 - 49 stories and 260 meters high - Accelerometers record motion - Loma Prieta earthquake was 100 km away - Shook for > 1 minute - Top swayed for > 30 cm
P Waves
- Compression - The fastest wave - Primary (first arriving) - Push-pull (type of particle motion) - Left and right particle motion (direction of propagation)
ShakeMap
- Computer-generated intensity maps of ground motion that show the distribution of maximum acceleration and maximum ground velocity during earthquakes - Incorporates modified Mercalli scale - Uses seismographs - Created with seismometers
The Parkfield "Prediction"
- Considered accurate forecast - Series of "repeating" earthquakes recognized (around M6 roughly every 20 years) - Estimated that probability of earthquake in next 30 years was 100% - Prediction was incorrect
Earthquake Rupture is a Critical Failure Process: Why Predictions are Hard
- Constant build up of stress - Fault patches failing (e.g., slipping) all the time - Most failure stays small, some become big
What was Wegener's theory of continental drift (how the continents spread apart)?
- Continents broke through crust that's underlying the ocean - Like an icebreaker plowing through weak crust under oceans - Theory later proven WRONG
Blue (Tomographic Maps Color Key)
- Cool rocks - High rigidity - Fast seismic velocity
National Earthquake Prediction Evaluation Council (NEPEC)
- Created in 1980 - Provide advice on earthquake hazard research - Assess predictions
The Consequences of Chemical Weapons (Rocky Mountain Arsenal)
- Created nasty by-products - Used well to inject these products
Slip on Faults (Release Loading)
- Creep measured by GPS - Need past events to forecast earthquakes.
What to Expect After Next Quake (Observed Building Failure Modes): Single Family Homes (Pre 1979)
- Cripple wall collapse - Homes knocked off foundations
Why do we need to strengthen buildings in LA?
- Current building codes protect life, not financial loss - Must build to a higher standards for continuing operation, not more expensive - Many older buildings are known to be more dangerous and require mandatory retrofit
Demographic and Economic Analysis of Haywired Scenario
- Damage to buildings will be a major impediment to business operations - Utility outages and transportations network - Interruptions will exacerbate employment loss in first year after earthquake - Many people will leave region after earthquake
Why would the SAFRR Tsunami Scenario be the largest economic impact to CA?
- Damages and incapacitates our ports and harbors - Damages coastal properties
What mostly occurs at plate boundaries?
- Deformation - Earthquakes
Requirements for Sending out Warning Before Shaking
- Dense sensor network (esp. close to fault) - Quick robust telecommunication from sensor - Algorithm for fast evaluation of event (location, magnitude, continued propagation along fault) - Quick, reliable mass notification - Liability protection - End user education
Turbidite
- Deposit on sea floor that gets deposited from landslides that come off continental margins - River brings sediment to shore that get deposited at shore
Mira Vista Golf Course: Northern Hayward Fault
- Depression (dip) on golf course called sag - Chose location bc gold course is prestine - Showed small offsets and evidence of 4.7 earthquake in past 1000 years - Most recent large earthquake found was around 1670-1776 (approximately around 1705)
Fortify the Water System (Recommendations): Shakeout Scenario of Los Angeles
- Develop alternative water system for firefighting - Fortify aqueducts (particularly where faults cross) - Fortify water storage (ex. dams) - Increase local sources of water: capture and clean up - Create seismic resilient pipe network
How does ShakeAlert sign up test users?
- Develop appropriate uses - Provide feedback - Implement automated responses
Elastic Rebound Theory
- Developed by Andrew Lawson and Reid - Continuing stress along a fault results in a buildup of elastic energy in the rocks, which is abruptly released when an earthquake occurs. - Earthquake is due to slip on a rupture in Earth's crust
Mexico City: Seismic Alert System
- Developed in 1989 in wake of 1985 Michoacán earthquake - 15 stations along coast - Station data transmitted to central processing in Mexico City - Warning issued when 2 stations indicated an event greater than M5 - Gives a minute of warning
Dealing w/ Hanging Objects: Step 1 of 7 Steps to Earthquake Preparedness
- Don't hang heavy objects above bed or sofa. Only soft object (unframed posters, rugs) - Hang mirrors, pics, other heavy object on closed pic hooks
Why do the magnetic fields flip?
- Due to the dynamics in the core
Logarithmic Scale
- Each step in magnitude means 10x more shaking and 32x more energy
User Application: MyShake
- Earthquake awareness - Education and preparedness
All Saint's Day (1755)
- Earthquake near offshore Portugal - One of the biggest earthquakes that struck the Earth - M > 8; 60k causalities - Happened during period of Enlightenment
Outlook in Oklahoma
- Earthquake rate declined by ~94% from 2015 to 2019 - 3 of 4 M5+ earthquakes since 2009 occurred in 2016 (includes the largest historic earthquake in Oklahoma) - Earthquake rate still elevated - Decline due to production decline of oil, gas, and water (caused by drop in oil and gas prices) - Injection decline due to regulation phased in 2015
MyShake 2.0
- Earthquake warning system developed by Berkeley - California's goal is to get 4 million people to download the app
ShakeAlert
- Earthquake warning system that opened in October 2019 - Alerts available for CA, Oregon, WA by technical and industrial users
Tsunami Generation Sources
- Earthquakes - Submarine explosions (volcano) - Landslides-terrestrial and submarine - Meteorite impact
What did Dr. Iben Browning argue?
- Earthquakes are triggered by gravitational attraction of moon and other planets. - Periodicity of alignments is 179 years.
How are earthquakes and pandemics related?
- Earthquakes can cause disease outbreak. - Pandemic increases earthquake vulnerability (in terms of preparedness).
Early Origin of Earthquakes: Christian Europe
- Earthquakes meant god's angry response to human sins - Earthquakes seen as "kismet" or "acts of god"
Denali Fault: Gillett Pass (2002)
- Edge of stream had 8.1 m of movement - Narrow rupture - We can now study fault geometrically since it's narrow.
Key Learning Points from Hayward Earthquake
- Elastic rebound and earthquake cycles at work - Quake recurrences are quite regular - Hayward fault is ready for its next Earth
Key Learning Points from Parkfield Earthquake
- Elastic rebound and earthquake cycles at work - Quake recurrences are quite regular - No obvious precursors
Example of Interdependences
- Electricity - WIFI - Water - Finances
Communication on natural hazards requires a combo of these disciplines...
- Emergency/disaster management - Geography - Public health
Soft Story Program (Berkeley)
- Enacted in 2014 - Mandatory retrofit of soft-story buildings w/ 5 or more dwellings - Apply for retrofit building permit by December 2016 - Work must be completed within 2 years - 85% buildings retrofitted
Non-ductile Concrete Retrofit Program (LA)
- Enacted in October 2015 - Construction permit prior to 1977 - Affects 1400 buildings in LA - Mandatory retrofit (or demolish) - 3 years to submit plan - 10 years to obtain permit - 25 years to complete work
Anak Krakatau
- Erupted in Indonesia in December 2018 - Underwater and barely emerging
Santa Barbara Building Codes
- Established in 1925 - Considered horizontal forces caused by earhtquakes
Strategies of Reducing Risk
- Estimating earthquake probabilities - Estimating fault slip and shaking levels - Designing buildings to withstand slip and shaking - Insurance to cover - Public policy to encourage/enforce risk mitigation - Rapid/short term warning and response systems
How do you install trenches inside the fault?
- Excavated by back hoes - Sometimes done by hand
Components of a Scenario: Output
- Exposed vulnerabilities - Scientific report and tools - Products, simulations, communication tools - Emergency response excercises
The Earthquake Quartet
- Expressed 2 ideas about earthquakes - Composed piece following 1999 earthquakes in Turkey and Taiwan
Normal Fault
- Fault created by tension - Hanging wall goes down, foot wall goes up - Fault is dip-slip - Strike and dip - Caused by extensional tectonic environments [see notes for beachball diagram]
Scientific Discovery: MyShake
- Fault detection - Micro seismicity
What did the Lawson Report map?
- Fault rupture - Ground shaking
What comes out of an earthquake cycle?
- Fault slip - Earthquake rupture - Creep
Dipping Fault
- Fault with an inclined fault plane - Has hanging and foot wall - Fault that isn't vertical
Basic Observations are Hard: Why Predictions are Hard
- Faults are buried km beneath the surface - Fault surfaces are heterogeneous - Faults are massive undulating surfaces below ground - State of stress on faults is very heterogeneous
Things to Check After Quake: Step 6 of 7 Steps to Earthquake Safety
- Fire - Gas leak - Damaged electrical wiring - Downed power line (stay away) - Falling items - Spills, damaged masonry
What info does surface rupture provide?
- Length - Slip distribution - Rupture complexity - Structure of endpoints (used in fault scaling relations)
How has direct fluid pressure effects of injection (fluid pressure diffusion) caused earthquakes?
- Fluids get into reservoir. - Sometimes fluid is connected into the fault and raises fluid pressure within that fault. - Pries fault apart, making it likely to slip (because it reduces friction on fault).
Examples of Mitigation
- Focusing on building codes - Understanding probability of earthquake
Example of Ductile Deformation
- Folding on compression - Sheering on tension - Stretching on strike slip fault
2009 L'Aquila Earthquake (Italy)
- Foreshocks between Nov 1 and Apr 6 - Aftershocks between Apr 6 and May 1 - Local prediction based on radon gas that got people concerned - Government council convenes and says no unusual hazard and tells people not to worry about it
What are some factors that have been observed before an earthquake?
- Foreshocks, seismic swarms - Change in velocity of seismic waves - Ground uplift - Radon gas - Electrical conductivity - Animal behaviors Note: None of these factors have been observed before ALL (big) earthquakes or even before many earthquakes.
Torsion Seismometer
- Frame twists around inertial mass - Light beam reflected off mirror "writes" on photographic paper
What two models joined together give you a better model?
- Geodetic - Joint
Where was the 1906 San Francisco Earthquake measured in?
- Germany - Holland - Japan
San Francisco's Geology
- Ground is soft - Can act as quicksand during earthquake (liquefaction)
Solomon Island (North of Australia)
- Had an earthquake and tsunami - Vulnerable due to recent civil war
Why was the Tohoku earthquake considered successful?
- Had sea wall, warning system, public education, and evacuation plan that reduced # of fatalities - Reduced risk
How was the Tohoku earthquake different from the Sumatra earthquake in terms of preparedness?
- Had sea walls and barriers - Had warning system - Had public education and drills
Clue #4: Sudden Land Subsidence (Pacific Northwest)
- Had sediment layers in Oregon ghost forest
Radioactive Heat
- Half of the heat reaching to the surface - Decay of Uranium and Thorium in mantle and crust that generates heat
Iceland
- Has a hot spot - Very active because it's above mid-atlantic ridge
Earthquake Rupture Source
- Has finite dimensions - Strike and dip (fault plate geometry) - Slip on fault - Surface varies - Rupture area: L x W - The steeper the dip, the more vertical
Clue #2: Cascadia Mountain Range (Pacific Northwest)
- Has many active volcanoes (active subduction zones)
Mid-Atlantic Ridge
- Has shallow earthquakes - Straightest plate boundary (from North America to Antarctica) - Has thousands of earthquakes - Moderate seismic activity
Tonga Subduction Zone
- Has some of the deepest earthquakes - Source of New Zealand earthquakes - Where Turkey earthquake M 6.7 occurred (Jan 24, 2020)
Which faults are most overdue and are most likely to rupture?
- Hayward - San Andreas
What are the most urban faults in California that have been most studied and has the most risks?
- Hayward - San Andreas
Earthquake Scenario 4
- Hayward (North + South Segments) - 8.5% probability in 30 years - 21% probability of any rupture on Hayward North in 30 years
Damages from Hayward Earthquake
- Heavy damage in San Leandro, Hayward, and Fremont - Old mission church destroyed
What does blue mean in seismic tomography?
- High rigidity - Cold rocks - Fast seismic velocity
Types of Seismographs
- Horizontal - Vertical
Red (Tomographic Maps Color Key)
- Hot rocks - Low rigidity - Slow seismic velocity
Alerting: Components of an Earthquake Early Warning System
- How fast - How accessible
Seismic Network: Components of an Earthquake Early Warning System
- How many sensors - How to send data - How fast
What We Know If We Know When the Flipping of Magnetic Fields Occurs
- How much and how fast the places moved away from each other - What orientation did the plates move away from each other
Algorithms: Components of an Earthquake Early Warning System
- How to detect - What area to warn - Accuracy (false/missed)
What went wrong during the 2004 M 9.1 Sumatra earthquake and tsunami?
- No warnings - People went to the beach to watch - Little awareness
After Determining Meeting Places: Step 2 of 7 Steps to Earthquake Preparedness
- Identify safe spots in home to go when shaking stops - Determine best escape routes from home and each room - Determine 2 best escape routes out of your neighborhood - Designate a neighbor or local friend's house as a safe place for your kids to meet if you're away from home - Install smoke alarms and test them monthly - Ask out-of-town friends to be your family disaster contact so your family can call them for emergencies
What can we learn from the earthquake drill conducted in New Zealand?
- If you ask people to help, they will help you collect data. - Observers rarely perform the drill. They perform the drill at a different time. - Gives people multiple ways to report back
Haywired Scenario: Building Damage
- Impact from shaking liquefaction, landslide, and fires leading to 50% of buildings extensively or completely damaged - $43 billion in damage ($80 billion w/ fires)
The Himalayas
- India subduct into Asia, creating continental collision (led to Himalayas) - Proves that continents continue to subduct
How did the Sumatra earthquake occur?
- Indoaustralian plate is subducting under Eurasian plate - Upper plates eventually snapped - Mostly horizontal motion but some vertical - Most energy travel perpendicular to strike of subduction zone
Wastewater Disposal
- Injection of water underground - Few connected to felt earthquake
Magnitude
- Instrumental measurements that account for the distance to the earthquake - A single number for each earthquake - A measure of the amplitude of ground shaking w/ respect to a reference point
Magnitude
- Instrumental measurements w/ seismometer that account for the distance to the quake source - A measure of the energy of the quake - Not dependent of location (one value per quake) - Has things to do w/ duration and offset of fault
What does the Haywired scenario focus on?
- Interdependencies of lifelines (especially internet) - Consideration of aftershocks
INSTAR (Synthetic Aperture Radar Interferometry)
- Interferes images - Has satellites in space to analyze Earth's surface - Electromagnetic wave reflected to create images - Can see every little fault move
What factors are needed to provide a useful earthquake prediction?
- Interval of time of when it will occur - Area of the location - Magnitude range - Probability earthquake will occur by change
Hydraulic Fracturing
- Invented in 1947 in Kansas - Makes small earthquakes - Causes fractures - High pressure injection to increase permeability - Short duration (hours) - Well goes into production
What is on an age progressive track?
- Juan de Fuca plate - Yellowstone Caldera
West Coast Plate Motion Faulting
- Juan de Fuca subduction - San Andreas Translation
Ridgecrest Sequence
- July 4: 6.4 Magnitude - July 5: 7.1 Magnitude - Around 1000 aftershocks
What are secondary hazards from the ARKStorm Scenario?
- Landslides - Flooding - Physical damages - Economic consequences
Examples of Secondary Effects
- Landslides - Liquefaction - Amplification
What are secondary processes in earthquake rupture effects?
- Landslides - Liquefaction - Tsunami
Triggered Hazards: Shakeout Scenario of Los Angeles
- Landslides - Utility disruption caused by fault offsets - Fire
Branches of communication research include...
- Language discourse - Critical public relations - Applied communications
ARKStorm Science: Prehistoric Megafloods
- Large regional flood events in the SBB area have occurred every few hundred years in prehistoric times
San Andreas Fault
- Largest fault in CA - Earthquake M>9 not possible - Named after San Andreas Valley - Right lateral - Moves 5 cm/year
Chris Goldfinger's Turbidite Record
- Layers of sand and mud corresponding to earthquake triggered turbidity currents - Full margin ruptures (~1000 km length meaning M9) - More frequent M9 at Southern end (every 220-240)
Stay Informed: Step 2 of 7 Steps to Earthquake Preparedness
- Learn disaster plans at workplace, child's school, daycare center, other places where family spends time - Give family members "Emergency Contact" card to carry w/ them. Include out-of-town contact, important contact phone numbers, and meeting locations.
Learn Lifesaving Actions: Step 2 of 7 Steps to Earthquake Preparedness
- Learn first aid and CPR from a class by Red Cross - Know where fire extinguisher is located - Learn how and when to turn off utilities (electricity, water, gas) - See if there's a community emergency response team (CERT) in your area
The 1906 San Francisco Earthquake: The Lawson Report
- Led by Professor Andrew Lawson (UC Berkeley) - Cataloged descriptions of earthquake effect - Identified San Andreas Fault - Maps of fault location and ground shaking distribution (showed intensity of shaking) - Developed elastic rebound theory w/ Reid
What are the climate change projections from ARKStorm?
- Likelihood of increasing flood risk - Changes large enough to pose important challenges in infrastructure and flood management
Plate Tectonics
- Loads faults - Measured using GPS
Northern Calaveras Fault
- Location of 1861 earthquake - Minor creep - 2 major earthquakes: 1861, 1740
Concord Green Valley Fault
- Location of 1954 M 5.5 earthquake (1605) - Creeps 4 mm/year
Greenville Fault
- Location of 1980 earthquake (M 5.8) - Creeps 2 mm/ year
Earthquakes that Influence Earthquake Preparedness
- Loma Prieta (1989) - Northridge (1994)
Wastewater Injection
- Long term (years-decades) - High volume - Many felt earthquake - Has caused 20+ damaging earthquakes -~35k wells
How do you see changes in seismic velocity?
- Look at stations - Measure propagation from earthquake to station along fault
How do you analyze trenches?
- Look where fault stops and shows displacement - Date them with charcoal to develop info of timing of individual events - Older deposits more deformed
What does red mean in seismic tomography?
- Low rigidity - Hot rocks - Slow seismic velocity
Southern Puerto Rico Earthquake (Amid Coronavirus)
- M 4.2 aftershock - Near southwest coastal town of Guánica - Hit during curfew that was meant to curve coronavirus - Arrived 3 months after big earthquake in Puerto Rico
Example of Ingredient 1
- M 4.6 in Southeast Missouri (September 1990) - Nobody died - Minor damage - Profound psychological damage
2016 M5+ Earthquakes in Oklahoma
- M 5.1 Fairview (rural area) - M 5.8 Pawnee (rural area) - M 5.0 Cushing (city; caused most damage)
Alum Rock Earthquake (2007)
- M 5.4 - First earthquake put to test for warning system or first event detected - Warning reached 4 stations - First detection (2 stations) took 19 seconds to get earthquake information - Took 15-20 seconds for warning to happen as a whole - 10 seconds of warning for San Francisco and Oakland
Salt Lake City, Utah Earthquake (Amid Coronavirus)
- M 5.7 - Caused chemical spill in nearby mine - Closed airports - Knocked out coronavirus hotline
Zagreb Earthquake (Amid Coronavirus)
- M 5.8 - Occurred during coronavirus lockdown - Demonstrated two parallel crisis that contradicted each other
1984 Morgan Hill Earthquake
- M 6.2 - Center of gymnasium roof swayed more than expected - Resulted in changes to uniform building code in 1991 - Code implied that buildings don't have to be modified
Long Beach Earthquake (1933)
- M 6.4 - Most damage seen in buildings
Idaho Earthquake (Amid Coronavirus)
- M 6.5 - 60+ aftershocks
Turkey Earthquake (January 24, 2020)
- M 6.7 - Had many aftershocks - Occurred on East Anatolian fault - Transform fault
1868 Hayward Earthquake (October 21)
- M 6.7-7 - Damages evident in San Leandro and Hayward - Caused by Hayward fault - Surface rupture from Fremont to Oakland
Dixie Valley, Nevada (1954)
- M 6.9 - 50k - Normal fault
Borah Peek, Idaho (1983)
- M 6.9 - Normal fault - Penultimate (~8 ka) surface rupture
The Haywired Scenario
- M 7.0 main shock (April 18, 2018) - Liquefaction - M 6.4 aftershock (May 27, 2018)
Christchurch Earthquake (2011)
- M 7.1 - Around 186 people died - Destroyed city - Land liquefied - Government bought land that could not be inhabited
Hebgen Lake, Montana (1959)
- M 7.3 - 28 km - Normal fault - Has trench installed
Landers, CA (1992)
- M 7.3 - 85 km in Mojave Desert - Moving for 300 years sideways
Guerrero Earthquake (1995)
- M 7.3 - Event successfully detected and alert was issued - 72 seconds of warning - No real damage in Mexico City
Chi Chi Earthquake, Taiwan (1999)
- M 7.6 - Ruptured through Kuangfu Middle School
Jamaica Earthquake (January 28, 2020)
- M 7.7 - Created seismic gap - 20x stronger than Puerto Rico earthquake (amplitude) and 39x stronger (shaking)
Denali Fault, AK (2002)
- M 7.9 - 310 km - Central Alaska, south of Alaska Range - 5 km offset - Stream flows through fault
1857 Parkfield Earthquake
- M 7.9 - Biggest earthquake in Southern California
Denali Earthquake (Alaska, 2002)
- M 7.9 - Strike-slip (in remote area) - Comparable to 1906 San Francisco earthquake - High hazard - Low-risk bc of little vulnerability and exposure - Normal footing across Denali fault
Why is retrofitting difficult?
- Politically challenging to require retrofit - Requires decades to fix building problems
1960 Chilean Earthquake
- M 9.5 - Tsunami reached Japan and had more impact than earthquake itself. - Tsunami also reached Hawaii. - Tsunami created many waves. (3rd wave was the strongest.) - No warning system.
1905 Bulnay Fault, Mongolia
- M ≥ 8 - 370 km - Repeated ruptures created mountains - 3 big earthquakes in 1905, 1957, 1931
South Napa Earthquake (2014)
- M6 - 12 km - Surface rupture near maximum slip: 46 cm - Occurred around 3AM - 9-23 cm of offset on street within a day after earthquake
Napa Earthquake: Earthquake Early Warning
- M6 (2014) - Blind zone: 16 km - Alert issued 5.1 seconds after earthquake began - 3.3 seconds after P wave at closer station - Police had 5 second warning - BART had 8 seconds - Google had 20 seconds - SFDEM had 9 seconds
Michoacán Earthquake (1985)
- M8 - 5000 people dead in city - Buildings collapsed - Encouraged Mexican government to build earthquake warning system
What are the number of earthquakes per year (roughly)?
- M8: 1 - M7: 10 - M6: 100 - M5: 1000
Tohoku, Japan Earthquake (2011)
- M9 - 3rd largest earthquake - Tsunami reached Bay Area and destroyed Santa Cruz Harbor
Cascadia Earthquake (January 26, 1700)
- M9 - January 26, 1700 - Tsunami occurred - Large infrequent earthquakes - Ghost forests created
Tohoku-Oki Earthquake (March 11)
- M9 - One of the 20 biggest earthquakes recorded - Created tsunami in West Coast California - 40-50 meter slip - Caused Fukushima power plant to explode (radiation spread east)
Fault creeps affect...
- Magnitude - Slip rate - Along strike dynamic rupture propagation - Co-seismic slip distribution - After slip - Ground motions
What should you do in days following earthquake?
- Make sure home is structurally safe - Unplug damaged electrical appliances, fixture, etc. - Stay informed w/ radio - Call out-of-town contact then stay off the phone
Class Goals
- Make you more aware of earthquakes - Make you more knowledgable about earthquakes - Make you prepared about the next big earthquake
Strengthening Buildings in LA (Recommendations): Shakeout Scenario of Los Angeles
- Mandatory retrofit of soft-first story buildings - Mandatory retrofit of concrete buildings - Back to business program; more inspectors to open buildings - Rating system for buildings
What is there today in the ghost forest?
- Marsh plants - Tidal mud - Sand deposited by tsunami - Old topsoil - Fire pit w/ charcoal used by Native Americans who settled near coast
Radon Gas
- May be released from bedrock prior to earthquake - Dilatancy produces fractures in ground and releases radon gas
Living in Condo or Apartment: Step 4 of 7 Steps to Earthquake Preparedness
- May have weak or "soft" first stories - Buildings built before 1972 w/ concrete or brick is inadequately reinforced - Less likely to be killed in retrofitted building but may not be able to recover after quake
Strike Angle (Azimuth)
- Measured clockwise from North - Angle in compass between strike line and North
Modified Mercalli Intensity Scale
- Measured ground motion (velocity/acceleration) at a location - Originally on scale from 1-10 but now a 12 point scale
Process of Creating Magnetic Field
- Mid-ocean mountain belts and ridges are areas where new magmatic rock and lava intrudes, solidifies, cools, and imprints whatever the magnetic field was at the time that rock cooled down. - After rock cools, it gets pushed to side. - Earth's magnetic field flipped 10 million years later. (Ex. North became south).
Causes of Induced Earthquakes
- Mining - Reservoirs - Wastewater injections - Hydraulic fracturing - Enhanced oil recovery
Seismic Moment
- Mo = δ*L*W*D - L*W*D = Multiply area of fault's rupture by the average slip on fault - δ = Shear modulus - Area of slip (L*W) multiplied by slip (D) and multiplied by rigidity of rock (δ) - Mo = Seismic moment in Newton meters
Northern Hayward Fault: Earthquake Ruptrues and Creep
- Most recent earthquake occurred between 1165-1776 (300 years ago) - At least 4 earthquakes occurred during ~2000 year interval - Average recurrence could be <270 years
Frequency of Damaging Earthquakes
- Mostly in Western U.S. - Some in Central U.S. and East Coast
Oblique Fault
- Motion is diagonal. - A combo of vertical and strike-slip movement - Right lateral strike slip fault + compression
Mid-Oceanic Ridges: Divergent
- Mountain chains that spread apart where the magnetic radiation are being formed (refer to drawing in notebook) - Had volcanic eruptions - New oceanic plate - Youngest in the middle; gets older as it spreads apart
Volcanoes on Cascadia Mountain Range
- Mt. Rainer (Seattle) - Mt. Hood (Portland) - Mt. St. Helens (1985)
Interdependence
- Mutual dependence between things - Disruption of service can create butterfly effect
California's Earthquake Early Warning System
- MyShake developed by Richard Allen - Up 20+ seconds of warning
Damage State of Immediate Occupancy: Performance Levels
- Negligible structural damage - Life safety maintained - Essential systems operational - Minor overall damage
Criteria for Prediction
- No false alarm - No missed earthquake based on precursor
Earthquake Prediction Failure in Tangshan (July 1976)
- No immediate precursors - No evacuation - More than 250,000 people died - One of the deadliest earthquakes
Transform Zones
- No plate creation or destruction - No volcanic activity - Shallow, moderate seismicity
What can be investigated w/ seismic data or forensic seismology?
- Nuclear test - Chemical explosions - Terrorist attack, building collapses - Mining accidents - Rock falls and land slides - Meteors
Two Types of Complex Movements in Fault
- Oblique fault - Partitioned slip
Limitations to Earthquake Drill Study in New Zealand
- Observer bias and interpretation - People act differently when being observed (Hawthorne effect) - Lack of individual identifiers - Accounting for cultural norms - Trauma from recent earthquakes
Susitna Glacier Thrust Fault
- Occurred during Denali earthquake - Ground rolled over - Fault ruptured through glacier and produced slip surface that could be measured
What did the full margin ruptures reveal from Chris Goldfinger's Turbidite Record?
- Occurred every 500-530 years on average - Minimum recurrence has been 110 years, max 1150 years
What are the losses if the Hayward earthquake (M 6.9) occurs again?
- Occurring on Hayward N+S - $23 billion (damage to buildings only)
Subduction Zone
- Oceanic plate destroyed - Explosive volcanic eruptions - Shallow to deep, vigorous seismicity
What happens if Cascadia (The Big One) occurs?
- Oceanic plate falls under continental plate - Elastic rebound will occur
Goose Creek, Texas (1925)
- Off coast of Houston - Earthquakes up to M4 caused by oil extraction (the only earthquakes felt in Houston)
What states enacted regulation on waste water disposal, hydraulic fracking, or both?
- Oklahoma - Kansas - Ohio - Texas - California - Arkansas - Colorado
Andrean of Islands, Alaska (1957)
- One of the 20 biggest earthquakes recorded - M 8.6
Rats Island, Alaska Earthquake (1965)
- One of the 20 biggest earthquakes recorded - M 8.7
Unimak Islands, Alaska Earthquake (1946)
- One of the 20 biggest earthquakes recorded - M 8.7
Chilean Earthquake (1960)
- One of the 20 biggest earthquakes recorded - M 9.5
Prince William (Alaska) Earthquake
- One of the 20 biggest earthquakes recorded - M. 9.2
Ivy Lee
- One of the founders of press agency - Worked for NY Times as a journalist - Became a freelancer - Worked for Atlantic Train Company in 1905
Body Waves
- P and S waves - Propagate away from source through Earth
What waves are created during an earthquake?
- P waves - S waves
How does the earth's core affect P waves and S waves?
- P waves slow down. - S waves cannot propagate.
Events After Farallon Plate
- Pacific Plate started to converge and connect w/ North America plate (its motion is parallel to the plate boundary rather than perpendicular - Switched from subduction faulting to strike slip faulting
1900 Year Long Earthquake History on Southern Hayward Fault
- Past 5 earthquakes are 131 +/- 72 years average interval - Past 9 earthquakes are 150 +/- 81 years average interval Past 12 earthquakes are 160 +/- 83 years average interval - Won't have another large earthquake for 8 years
How is the past key to the present in earthquake research?
- Past geological events can be explained by phenomena and forces observable today - Seeing how geological processes and natural laws modify the Earth's crust (how crust acted with same intensity throughout geological time)
What did the California survey reveal?
- People support the earthquake warning system - California should dedicate funds even if it cost tax payers
Intensity
- People's descriptions of what they felt - Observations of damage to buildings varies by location - Measured ground motion (velocity/acceleration) at a location - Damage to structures and natural features
Consider: Where will your family/friends be? (Earthquake Preparedness
- Pets aren't allowed in most emergency shelters. - Friends could be anywhere across campus or away. - Pets may run away or be scared. - Family members could be at work, school, etc.
Plate Tectonics Model
- Physical model - Predicts that future earthquakes will occur at plate boundaries - Basis of earthquake hazard models
Cushing
- Place of national security infrastructure - Has high earthquake risk - Aka pipeline crossroads of the world
What do hotspots reveal?
- Plate movement - Upwelling mantle plumes
Western Pacific Plate
- Plates are subjecting to the west - Subduction zones - Vigorous seismicity - Shallow too deep
The Origin of Yellowstone
- Plumes producing low velocity - Hot spot broke through slab - Has strings of volcanos
Integrating Across Disciplines: Building the Scenario
- Policy - Social sciences (social impact, economic impact, emergency response, casualties) - Engineering (lifeline, triggered hazard, structures, infrastructure) - Earth science (secondary hazard, shaking, the fault)
The ARKStorm Scenario
- Precipitation exceeding levels experienced on average on every 500-1000 years - Secondary hazards - ARS w/ most water vapor, strongest winds, and that stall over watershed can create extreme rainfall and floods - Central Valley flooded over about 300 miles long, 12-60 miles wide
Earthquake Prediction Success in Haicheng, China (February 1975)
- Predicted an imminent earthquake - Evacuation ordered - A large earthquake struck 9 hours later - Destroyed many homes but little loss to life
Earthquake Prediction Failure in Kwangtung Province (August 1976)
- Predicted an imminent earthquake - Evacuation ordered - People slept in tents for nearly 2 months - No earthquake occured
FEMA National Preparedness Report
- Preparedness campaigns (ex. Ready.gov) has not improved level of preparedness in households - Often in disappointment
How is situation awareness a benefit of warning system?
- Prevents cascading failures - Gives response centers and firefighters a heads up
Heat Sources that Drive Convection
- Primordial heat - Radioactive heat
Forecast
- Probabilistic assessment of earthquake occurrence - Time window, only estimate of location and magnitude - Based on observations and probabilistic assessment of earthquake occurrence - Long time window (30 years) w/ estimate of location, magnitude, shaking, and risk
Damage State of Life Safety: Performance Levels
- Probable structural damage - No collapse - No falling hazard - Adequate emergency egress
Positive Impact of Earthquake Prediction: Broader Social Impacts
- Property changes - Financial changes - Population movement - Level of business activity - Preparedness organization and education - Rescheduling of public events - Reduction in public services
Magnetic Stripes
- Provide evidence of sea floor spreading when they show the reversal of magnetic fields - Measured strength of magnetic field as ships moved around ocean - Strength and orientation of field varied as ships moved around - Systematic patterns of strong, weak, strong
Related Terms in Emergency management
- Public education - Public information
Bathymetry Examples Shown in Class
- Puerto Rico Trench - East Pacific Rise
What happened to the Members of Council in Italy?
- Put on trial for manslaughter in Italy - Accused of failing to predict an earthquake that killed 300+ people - Published inaccurate information about dangers of seismic activity undermining protection of population
What are examples of mixed methods in observational research?
- Qualitative analysis - Quantitative analysis
Operational Earthquake Forecasting (OEF)
- Quantify raised hazard of earthquake - Provide probability of aftershocks (aftershock forecast) and earthquakes in general - Time dependent and short term earthquake forecasting that considers earthquake clustering and possible precursor
Surface Waves
- Rayleigh and love waves - Propagate along upper few km of earth - Restricted to uppermost layer of the Earth - Limit themselves to surface
What determines the magnitude?
- Real fault ruptures - Fault endpoints - How deep the fault extends into crust
The Results of the Long Beach Earthquake
- Recognized failure of unreinforced masonry bearing walls (was the common building standard at the time) - Led to 1933 Field Act - Led to Riley Act - Led to 1939 Garrison Act - Led to Greene Act
Early Origins of Earthquakes: Japan
- Records from 1600 AD - Some from 416 AD
Early Origins of Earthquakes: Greece to Afghanistan
- Records from 300 AD - Some from early writing of the bible
How does the Haywired scenario affect the water system?
- Shaking, liquefaction, and fault rupture results in extensive water main breaks - Its failure makes immediate fire fighting difficult Requires month restoration for some communities if there's extensive failures
S Waves
- Shear wave - The strongest wave - Secondary (second arrival) - Shears side to side (transverse) - Motion of particles is perpendicular to propagation of wave (up and down)
Fracking
- Short term (hours-days) - Low volume - Few felt earthquake - Few damaging earthquakes - > 1 million frac stages
Result of Compressional Tectonic Environments (Reverse and Thrust Faults)
- Shortening - Mountain building
Maps in the 1960s
- Showed Ring of Fire - Mapped more earthquakes (topographic features
Evidence of Fault Creep in Hollister
- Side of curb moved (see slide) - Steady progression on Hayward Fault not associated w/ an earthquake (about 2.5 mm/year)
Building Codes
- Regulations governing design, construction, alteration, and maintenance of structures - Specifies minimum requirements to safeguard health, safety, and welfare of building occupants - Exist for all aspects of building design - Concept not developed w/ earthquakes in mind - Initiated in US in 1920s
Solutions to Soft Story Buildings
- Reinforced walls - Extra bolts and braces drilled into foundation - Columns should be replaced or retrofitted w/ steel frames
Components of a Scenario: Outcome
- Relationship - Research - Application - Mitigation - Education - Resilience
Antonio Snider-Pellegrini
- Religious - Published sketches of continent separation (showing before and after) - Thought expansion explained features of Earth (ex. rocks) - Through Earth expanded during genesis - Thought separation of land meant expansion of Earth
How can we prevent damage from column failure?
- Retrofit: Casing around existing columns - New columns: Continuous steel spirals around vertical steel rods - $12 billion highway bridge earthquake strengthening program
Subduction Zone
- Reverse fault (compression) - Convergent boundary (see notebook for diagram)
In what directions do strike slip faults move in?
- Right lateral - Left lateral
Hayward Fault
- Right lateral slip - The fault crossing Berkeley - Beheaded creek channels
San Andreas: West Coast Plate Motion Faulting
- Right lateral strike slip - Caused by translation/transform - Moves 4 cm.year (rate of deformation)
What does forecasting quantify?
- Risk - Expected losses
What two factors can we tackle?
- Risk - Vulnerability
Consider: Will you be able to get home? (Earthquake Preparedness)
- Road damage and closure may restrict your ability to travel by car. - Public transportation (bus, BART, ferries, airports) may experience closure or interruption in service. - Commute times may drastically increase.
How do S and P waves change as they travel through the mantle?
- S and P wave velocity increase in the mantle when you get to the outer core. - P wave velocity drops. - S wave disappears and can't propagate through outer core (bc outer core is convecting and is producing outer field)
Which regions contributed to the earthquake death toll from the last century
- SF - Pero: 66k - Messina, Italy: 85k - Turkmenistan: 110k - Gansu & Xining, China: 200k - Tangshan, China: 250-500k - Tokyo, Japan: 143k
Examples of Right Lateral Faults
- San Andreas - Christchurch, New Zealand
Earthquake Scenario 1
- San Andreas - Repeat of 1906 - 4.7% probability in 30 years
Earthquake Scenario 2
- San Andreas (Peninsula Segment) - 4.4% probability in 30 years
Earthquake Scenario 3
- San Andreas (South Segment) - 2.6% probability in 30 years
Faults w/ Creeping and Locked Faults
- San Andreas Fault - Calaveras Fault - Hayward Fault - Greenville Fault
Bay Area Faults
- San Andreas translation - Right lateral - Moves 5 cm/year (even beyond Bay Area)
Dealing w/ Furniture and Home Electronics: Step 1 of 7 Steps to Earthquake Preparedness
- Secure furniture to the wall to keep it from falling w/ flexible-mount fasteners or nylon straps - Secure top corners of tall furniture into a wall stud, not just to drywall - Secure heavy items (ex. TV, stereo, computers)
Physical Parameters in Precursor Stages
- Seismic p velocity - Ground uplift and tilt - Radon emission - Electrical resistivity - Number of local earthquakes
What instruments record ground motion?
- Seismometers - Accelerometers
When did the next Parkfield earthquake occur and what was the magnitude?
- September 28, 2004 - M6
What did the Parkfield Prediction Experiment reveal?
- Series of "repeating" earthquakes recognized that helped predict next earthquake
Damage State of Collapse Prevention: Performance Levels
- Severe structural damage - Collapse - Probable falling hazard - Possible restricted egress
SAFRR Project Scenarios
- Shakeout - ARKstorm - Tsunami Scenario - Haywired
What do scientists need to measure to understand the solid Earth processes?
- Shaking - Fault length, area, slip, etc.
Shakeout Scenario: Results
- Significant injuries (50,000) - 1800 deaths - $213 billion damages - 300k buildings damaged - Transportation interrupted - Lifeline disruption - Fires following earthquake - Damaging aftershock sequences may occur for a decade
Other Methods that Drive Plate Tectonics
- Slab pull - Ridge push - Bottom drag - Hot spots
Damage State of Damage Control: Performance Levels
- Slight structural damage - Life safety attainable - Essential systems repairable - Moderate overall damage
Identified Hazard: Denali Earthquake
- Slip on Denali Fault - Shaking from fault
Offset Post-Glacial Outwash Fan Eastern Denali Fault, AK
- Slip rate: 8mm/year - Trench revealed most recent earthquake is 100-300 years ago
How do scientists and industries interact with the public and decision makers (in Oklahoma)?
- Slow to react - Modern approach - Permitting hearings now well-attended
Benefits of Early Earthquake Warning System
- Slow/stop train to avoid derailment - Power down computer, transformers - Open firehouse/garage doors - Stop elevator at nearest floor and open - Start generator - Stop assembly line in factories - Warn dentist/surgeon - Shut down, close, secure pipes/container w/ hazardous chemicals
How is automated control a benefit of earthquake warning system?
- Slowing and stopping trains - Isolating hazardous machinery and chemical - Data security
What intensifies shaking even if they're far away from the fault?
- Soft bay muds - Young sedimentary basin
Modes of Building Failure
- Soil failure/liquefaction - Narrow based structure - Bending/weak structure - Partial wall collapse
Hazard
- Something that has the potential to harm you - What nature presents to us - The hazard of earthquakes related to plate tectonic and fualts
Earthquake Machine Experiment (Shown in Class)
- Sound represent shaking - Cube attached to string - Putting rock on cube represents stronger earthquake
Components of a Scenario: Working Groups
- Source - Secondary hazard - Physical damage
Wave Heights in California
- Southern California has lower wave heights than Central and North coast. - Some areas completely submerged
Probabilistic Ground Shaking (Engineering Version)
- Spectral acceleration at 1 second in % g - Scale goes up to 2.5 g - With 2% probability of exceedance in 50 years (during 50 year lifetime of a building there is a 2% chance of stronger shaking)
Examples of Seismic Hazards
- Speed of tectonic movement - Size of quakes - Location of and distance from faults - Locked or a seismic creep - Quality of soil (liquefaction) - Shaking intensity - Tsunami - Landslides
How can you reduce vulnerability (sun scenario)?
- Staying out of the sun - applying sunblock
Dealing w/ Objects on Open Shelves and Tabletops: Step 1 of 7 Steps to Earthquake Preparedness
- Store heavy items and breakables on lower shelves - Secure valuable items in place w/ removable putty, museum wax, or quake gel
Transform Plate Boundary
- Strike slip - Shear (see notebook for diagram)
Eastern Indonesia Earthquake (Amid Coronavirus)
- Strong inland and shallow earthquake in Sulawesi - Sent people fleeing despite social distancing protocal
In what circumstance should you evacuate your home after an earthquake?
- Structurally unsound - At fire risk
Soft Story Buidings
- Structurally weak first stories (ex. apartment w/ carports) - Have collapse risk in moderate earthquakes
Clue #3: Ghost Forest Along Coast (Pacific Northwest)
- Stumps sticking out of center - All stumps had same death year
Result of Extensional Tectonic Environments (Subsidence and Basin Formation)
- Subsidence - Basin formation
Nigata (1964)
- Sudden subsidence near future epicenter in year prior - Data was suspect
What did the South Napa earthquake (2014) reveal about buildings?
- Unreinforced buildings continued to experience damage - Retrofitted unreinforced masonry buildings performed well (ex. reinforced w/ steel bars)
How can we change the way we talk about preparedness and disasters?
- Use cultural sensitivity models - Expand our language (ex. translating infographics to Spanish)
Seismic Imaging
- Used to see how long it takes for seismic waves to get from source - Can figure out which paths took longer to get to your station on average than others
Focal Mechanism Beach Balls
- Used to show the sense of motion that occurred on a fault during an earthquake - There are always 2 lines
Bathymetry
- Using ships to measure ocean depths and chart the shape or topography of the ocean floor - Shows mountain belts and trenches
What areas were impacted by the tsunami from the Sumatra earthquake?
- Sumatra - Thailand - Sri Lanka - Maldives - East Africa - Hawaii
Epicenter
- Surface of Earth above hypocenter - Actual point in Earth where earthquake starts
Strike Line
- Surface of a lake makes horizontal line along surface - Intersection of plane w/ horizontal line
Earthquake Rupture Effects
- Surface rupture - Ground shaking - Secondary processes
All the Models
- Teleseismic - Seismic - Geodetic - Joint - Tsunami
Refraction
- The bending of a wave as it passes at an angle from one medium to another - What waves to when they encounter material interface to material w/ different velocity
What does an earthquake source/focal mechanism describe?
- The direction of slip in an earthquake - The orientation of the fault on which it occurs - Fault movement
What you feel during an earthquake is a product of:
- The earthquake itself - How far you are from the earthquake - Types of rocks between you and the earthquake - The rock below you
How was the Trans-Alaska Pipeline successful during the Denali Earthquake?
- The fault slip and shaking hazard was identified - Pipeline was constructed to accommodate slip and shaking - No damage
Richter Magnitude
- The first magnitude - No longer used today - Was never reported - Magnitude is a log10 of the maximum amplitude recorded on a Wood-Anderson seismometer at 100km from the epicenter
Why/how should you take action to recover?
- The government won't save you. - Relief efforts intended to help w/ immediate needs and won't replace lost items - Take out loans (max. $40k per home)
Risk
- The likelihood of a hazard causing harm - Susceptibility to hazard - (Hazard) x (vulnerability)
What do earthquake waves (shaking) inform us?
- The nature of the earthquake source - Distance from the earthquake - Traverse rock types
Epicenter
- The point on the Earth's surface directly above the focus of an earthquake - Where an earthquake OCCURS
Convection
- The transfer of heat from deep in the earth to the surface - Hot (buoyant) upwellings, cold (dense) downwelling - Cooling down, solidifying, making oceanic lithosphere, getting colder sitting at surface and diving back down into Earth
Hypocenter
- The underground focus point of an earthquake - Where an earthquake STARTS
How do we make seismic hazard estimates?
- Using observations and understanding of real fault ruptures that include length - Seeing what endpoints might look like - Analyzing amount of slip on fault
Earthquake Forecasting
- Using past earthquake history to predict the next earthquake - Installation of instruments into fault to get data
BART
1st automated transit response to earthquake early warning system in US
Plate Boundaries
- The whole interface and zones that can be 100 km wide between 2 plates - Area below 2 plates
Continental Drift
- Theory proposed by Alfred Wegener - Said there used to be a super continent (Pangaea) and continents drifted apart since age of dinosaurs
How are fault segments, fault systems, faults, and fault clusters defined?
- There are smaller faults within large faults that make up the San Andreas zone. - They host small and large earthquakes that cluster in space and time.
Coachella Paleoseismic Site: Southern San Andreas Fault
- There's multiple lines of evidence for surface rupture in multiple trenches. - Excavate wide trenches - Trenches showed evidence of 7 wide earthquakes.
What matters in a tsunami scenario?
- Tides - Location - Currents - Time - Response
What does building earthquake resilience require?
- Time - Money
Positive Impact of Earthquake Prediction
- Time for evacuation (can save lives and prevent injury) - Broader social impacts
What did the 2004 Parkfield earthquake reveal?
- Took another 16 years after predicted year - No obvious precursors were found
Clue #5: Tsunami Records in Japan (Pacific Northwest)
- Town of Otsuchi, Japan damaged by a tsunami in 1700 - Must have come from Cascadia plate - Had orphan tsunami (no earthquake felt)
Potential Environmental Impact from Tsunami
- Toxicant in debris - Petroleum from refineries, terminal, and vessels - Dry bulk (industrial borate) - Smoke ash, debris from fires - Contaminated sediment
Communication
- Transactional process where people generate meaning through the exchange of verbal and non-verbal messages in specific contexts, influenced by individual and societal forces and embedded in culture - Can be both an art (creative/critical discourse) and a science (social sciences) - Umbrella term for public relations, media relations, marketing, and associated sub-disciplines
West Fork Plateu Site: West Central Fault, Alaska
- Trenches done by shovels (excavated) - Near Denali
Induced Earthquakes Bigger than M>3
- Trinidad, CO Earthquake M 5.3 - Prague, OK Earthquake M5.7
SAFRR Tsunami Scenario
- Tsunami generated by a M 9.1 earthquake offshore Alaska peninsula - Rupture similar to Tohoku - Simulations of tsunami waves impacting U.S. West Coast - Biggest contribution to LA's tsunami hazard
Examples of Gap Filling Earthquakes
- Turkey - Jamaica
1906 San Francisco Earthquake (April 18)
- Turning point for modern earthquake science - Started in water - Caused slight tsunami
Consider: Could you live without the services you rely on? What services will you mostly miss? (Earthquake Preparedness)
- Water may be in short supply. - Natural gas and electric power may be out for days/weeks. - Garbage and sewage may be interrupted - Telephone, internet, cell phone, wireless communication may be overloaded/unavailable. - Mail service may be disrupted. - Gas may be in short supply; rationing maybe necessary. - Bank operations may be disrupted, limiting access to cash, ATMs, or online banking. - Grocery, drug, and other retail stores may be closed or unable to restock shelves.
Co-produced Water (Wastewater)
- Water that comes up when you extract oil and gas - In all wells
What happens as water depth decreases (waves getting shorter/gets closer to shore)?
- Waves get slower and bigger. - Energy gets concentrated at smaller distances. - Wave amplitude decreases.
Surface Waves
- Waves that travel across the surface of the Earth - Side to side particle motion in horizontal wave - Love and Rayleigh waves
Body Waves
- Waves that travel through the "body" of the Earth (travel through Earth's interior) in every direction possible - P and S waves
Why is it difficult to measure electrical conductivity?
- We make so much electrical noise - Difficult to make a measurement that isn't contaminated by electrical activity we produce ourselves - Too many manmade signals
Examples of Convergent Plate Boundaries
- Western South America - Japan - The Himilayas
Questions to Ask as a Renter: Step 4 of 7 Steps to Earthquake Preparedness
- What measures have been taken to ensure building safety? - Have water heaters been strapped to wall stud? - Can I secure bookshelves and furniture to walls
Scenario Retrospective
- What was innovated - How was/wasn't it used - Who used it - How muc risk reduced
Crescent City, Northern CA
- Where sea floor make tsunamis have larger heights - Hit by tsunamis 32 times between 1933 and 2011
Consider: Will you be able to stay in your dorm, apartment, or home? (Earthquake Preparedness)
- Where you live may have been destroyed - Alternate rental housing may be limited or not available
Users: Components of an Earthquake Early Warning System
- Who get warning (via news, app, etc) - What action - How fast
Pre-1979 Single Family Homes
- Wood framed but are weak bc they're not tied to foundation - Has sliding, racking, and overturning
Components of a Scenario
- Working groups - Output - Outcome
Ivy Lee's Role at Atlantic Train Company (1905)
- Wrote "statement from the road" that talked about the derailment/collapse of Atlantic Bridge (Atlantic City Train Wreck) - 1st evidence of media release
Horizontal (Seismograph)
- X Axis (Side to side) - Y Axis (Up and down)
Magnitude-Number (Guttenberg-Richter) Relation
- logN = a-bM - N = # of earthquakes - M = Magnitude - a and b = Constant - Global average for b is ~1
Age of Oceanic Plates
0 to 280 million years
Hayward Earthquake Rate
1 every ~190 years
What is the chance that a larger main shock would happen after an aftershock in California?
1 in 20 earthquakes are followed by larger quake.
Principles of a Scenario
1. A Single large but plausible event 2. An event we need to be ready for 3. Integrate across many disciplines 4. Use best hazard science 5. Consensus among leading expert 6. Create study w/ community partners 7. Results presented in products that fit the user, not scientist
What constitutes a scenario?
1. A single, large but plausible event 2. An event we need to be ready for 3. Integrate across many disciplines 4. Use best hazard science 5. Consensus among leading experts 6. Create study w/ community partners 7. Results presented in products that fit user, not scientist
Purposes of MyShake 2.0
1. Alert delivery 2. Earthquake detection system
Transform Summary
1. Along mid-ocean ridges - Fracture zones (ex. S. Pacific) 2. Across continents - San Andreas Fault
What does the development of a long record require?
1. An exceptional site w/ excellent preservation of strata 2. Abundant dateable material (ex. peets and seeds)
What is a magnitude dependent on?
1. Area of fault plane that ruptures (length x depth) 2. Distance the fault slips during earthquake
What can we use to calculate the probability of an earthquake rupture on a fault?
1. Average recurrence interval 2. Variability (coefficient of variation) 3. Amount of time (elapsed time) since most recent large earthquake)
Why Predictions are Hard
1. Basic observations are hard 2. Earthquake rupture is a critical failure process
Precursory Stages
1. Buildup of elastic strain 2. Dilatancy (formation of cracks) and development of cracks 3. Influx of water and unstable deformation in fault zone 4. Sudden drop in stress followed by aftershocks
More Magnitude Scales
1. Codd or Duration Magnitude 2. Local Magnitude 3. Body Wave Magnitude 4. Surface Wave Magnitude
Formation of Ghost Forest in Subduction Zone
1. Continental plate is locked by friction to diving oceanic plate (oceanic plate is going below continental plate) 2. Stress builds as leading edge of plate is shoved back 3. Potential energy is stored as land rises 4. Friction is overcome in elastic rebound and overlying plate rebounds, producing a great earthquake 5. Leading edge jumps out and up beneath sea 6. Tsunami forms 7. Forest dropped below sea level and dies 8. Tree roots die in salty marsh 9. Process begins anew and ghost forest is raised above sea level
What is UC Berkeley doing for seismic retrofitting?
1. Continuous process of evaluation and improvement where first assessment started in 1975. 250 million spent retrofitting 18 buildings by mid-1990s. SAFER project started in 1997 where 1 billion was spent on retrofitting dozens of buildings 2. Current initiative started in 2017 where there's a new assessment of all buildings using the current state of knowledge.
Cycle of Crisis
1. Crisis preparedness 2. Crisis prevention (prevent harm) 3. Crisis event management (emergency response) 4. Post crisis management (recovery)
What theory is needed for earthquake prediction?
1. Criteria for slip to start (nucleation point) 2. Process of rupture propagation across fault 3. Criteria for slip to sop at a point determining magnitude
Factors Determining Size of an Earthquake
1. Death/injured 2. Cost of damage (impact of quake)
What does velocity depend on?
1. Density 2. Elastic constant describing rock behavior
What does intensity depend on?
1. Distance from fault 2. Rock type (material underneath you)
What are the 3 scales on the nonogram?
1. Distance/S-P time 2. Magnitude 3. Amplitude
3 Types of Plate Boundary
1. Divergent 2. Convergent 3. Transform
The 2 Ideas from the Earthquake Quartet
1. Earthquake cycle 2. Ignoring cycle will have consequences
Purposes of MyShake
1. Earthquake detection and alert 2. Seismic wave form data
Process to Generate Alert
1. Earthquake nucleates underground (at hypocenter), fault slips 2. P wave propagates and gets detected by closest station 3. Station uses information to develop warning.
How many instruments do you need to measure horizontal and vertical motions?
2 (horizontal and vertical seismographs)
Success Story of Trans-Alaska Pipeline (1973-1974)
1. Fault identified 2. Uncertainty in location defined 3. 6m design offset developed 4. Innovation design w/ skids 5. Event occurs w/ 5m offset 6. Pipeline rese to pre-2002 configuration
What are two methods that use seismic waves to determine if it was a bomb or an earthquake?
1. Focal Mechanisms 2. Seismographs
General Improvements of LA: Shakeout Scenario of Los Angeles
1. Fortify water system 2. Strengthen buildings
What two things make risk?
1. Hazards 2. Vulnerability
Common Observations in Long Beach Earthquake
1. Houses tossed off foundations. 2. School buildings collapsed (230 destroyed, major damage, or unsafe to occupy)
What info is needed for a nonogram?
1. How far earthquake is (S-P distance) 2. Amplitude 3. Use 1 and 2 to find magnitude (connect values)
Factors Determining How Big an Earthquake Is
1. How much slip there is 2. How big rupture area is 3. How fast rupture slip
Different Oil and Gas Operations Causing Earthquakes
1. Hydraulic fracturing 2. Oil production 3. Wastewater disposal 4. Enhanced oil recovery
7 Steps to Earthquake Safety
1. Identify potential hazards in your room and home and begin to fix them. 2. Create a disaster preparedness plan. 3. Prepare disaster kits. 4. Identify your buildings potential weaknesses and begin to fix them. 5. Protect yourself during an earthquake. 6. Check for injuries and damages after the quake. 7. When safe, continue following disaster plan.
How to Reduce Risk
1. Identify, understand, and quantify hazard. 2. Identify, understand, and quantify risk. 3. Reduce vulnerability and risk to acceptable levels.
Parameters Affecting Injection
1. Injection rate 2. Total Injected volume (no connection to EQ) 3. Proximity to basement (no connection to EQ) 4. Injection pressure (no connection to EQ)
Layers of the Earth (From Center to Top)
1. Inner core 2. Outer core 3. Mantle 4. Crust
Building Up to an Earthquake in Subduction Zones
1. Island gradually sinking 2. Island pops up (earthquakes trigger tsuanmi) 3. Tsunami (displaces sea floor
Which two earthquakes occurred at the Caribbean Plate?
1. Jamaica Earthquake (M 7.7) 2. Puerto Rico Earthquake (M. 6.4)
Other Explanations of Plate Tectonics
1. Land masses sank as Earth cooled and contracted. 2. Land bridges between continents could explain the fossil record. 3. Expanding earth, shrinking earth
Layers of Earth (Top to Bottom)
1. Lithosphere 2. Asthenosphere 3. Mantle
What observations are needed to analyze earthquake rupture?
1. Location of all faults 2. Stress on faults (on every patch) 3. Physical properties of fault surface (every patch)
What factors control shaking intensity at a site?
1. Magnitude of earthquake 2. Closest distance of the site to the fault rupture 3. Ground condition of site (rock vs. soil vs. landfill)
Divergent Summary
1. Mid-ocean ridge - Mid Atlantic Ridge 2. New rift zone, new ocean - East African Rift
Focal Mechanisms for 3 Basic Faults
1. Normal 2. Thrust 3. Strike Slip
Three Main Faults
1. Normal (extension) 2 Reverse (compression) 3. Strike-slip (sideways)
3 Types of Faults
1. Normal fault 2. Reverse and thrust fault 3. Strike slip fault
3 Key Parts (Diverse Observations) of Plate Tectonics
1. Ocean bathymetry (ridges and trenches) 2. Global distribution of earthquakes 3. Magnetic stripes on ocean floor
Convergent Summary
1. Ocean-continent - Off West Coast of S. America 2. Ocean-ocean - Japan trench 3. Continent-continent - W. Pacific Himalaya
5 Major Areas of Loss: Shakeout Scenario of Los Angeles
1. Older buildings built to early standards 2. Nonstructural elements and content 3. Infrastructure across the San Andreas Fault 4. Business Interruption due to damaged infrastructure (including telecommunications and water) 5. Fire following earthquakes
Which areas (inundation zones) will the SAFRR Tsunami scenario impact?
1. Orange County-Huntington Beach 2. LA County-Long Beach
Types of Waves
1. P Wave 2. S Wave 3. Rayleigh Wave 4 Love Wave
What happened as the December 3 (predicted earthquake date) approached?
1. Parents demanded that the schools close because its buildings weren't designed for earthquakes. 2. Shops sold out of flashlights, sleeping bags, canned food, batteries, and booze. 3. Many people left town. Others camped outside for the weekend. 4. Media arrived in town. Anchors interviewed people hoping to have cameras rolling when earthquake struck.
Benefits of ShakeAlert
1. Personal safety 2. Automated control 3. Situation awareness
How are earthquakes a balancing act?
1. Plate motions continually load strain on fault. 2. Fault slip occurs during earthquake releasing strain.
Critical Areas that Could Be Addressed by LA City Policy
1. Pre-1980 soft first story buildings 2. PRe-1980 non-ductile reinforced concrete building 3. Water infrastructure (including firefighting) 4. Communications Infrastructure
Studying Human Behavior In Earthquake Drill: The Steps
1. Prepare forms and identify observers in the organization 2. Conduct the national drill. Observers watch and fill out forms w/ impressions of drill. 3. Send GNS science form via survey monkey, mail, fax, or email.
Seismic waves are subject to...
1. Refraction 2. Reflection
Alternatives to Wastewater
1. Reuse frac fluid 2. Surface discharge 3. Disposal at depth
What clues indicate that the Pacific Northwest is prone to earthquakes?
1. Ring of Fire 2. Cascadia Mountains 3. Ghost forest along coast 4. Sudden land subsidence 5. Tsunami records in Japan
What two types of places should you choose when creating a disaster preparedness plan?
1. Safe place to meet near your home after shaking stops 2. A place outside your neighborhood (in case you have to evacuate neighborhood or cannot return home)
MyShake: A Virtuous Circle
1. Scientific discovery 2. Hazard reduction 3. User application 4. Citizen science
Components of an Earthquake Early Warning System
1. Seismic network 2. Algorithms 3. Users 4. Alerting
What items are needed to create a ShakeMap?
1. Seismic station 2. Seismograph
Evidence of Continental Drift
1. Similar fossils 2. Similar rock formations across boundaries
Characteristics of Induced Earthquakes
1. Spatial Correlation 2. Temporal Correlation 3. Near Surface (Shallow Depth) These 3 characteristics ARE NOT a criteria.
The Elastic Rebound Theory: The Steps
1. Stress builds up due to tectonic plates moving past one another 2. Friction along fault prevents slip, elastic deformation instead 3. Stress exceeds fault strength, fault slips earthquake
Two Messaging Products: SAFRR Tsunami SCenario
1. Sue Nami 2. Tsunami Walk
How to Measure Plate Tectonics w/ a GPS
1. Take an antennae and set up over benchmark 2. Center antennae above cross on benchmark 3. Measure longitude elevation 4. Repeat process after certain amount of years to see changes
Probabilistic Ground Shaking
1. Take predicted ground shaking. 2. Take probability of each earthquake. 3. Calculate probability that ground shaking will exceed some level.
Strike slip earthquakes can make a large tsunami if...
1. They set off large landslide offshore 2. Rupture w/ vertical displacement
What 2 subduction zones are within the Caribbean Plate?
1. West (where Cocos plate is subjecting to West) 2. East (where N. American plate under Atlantic is subducting)
What do we have to pinpoint for an earthquake prediction to be useful?
1. When next earthquake will be 2. Where earthquake and which fault/area is affected 3. How strong earthquake will be (must be quantified in many narrow terms)
Things to Consider For Earthquake Preparedness
1. Will you be able to get home? 2. Where will your family/friends be? 3. Will you have medical services? 4. Will you be able to stay in your dorm, apartment, or home? 5. Could you live without the services you rely on? What services will you mostly miss?
What are the 3 components in MyShake?
1. X axis 2. Y axis 3. Z axis
How many points did the Mercalli Intensity Scale originally have?
10
What % of buildings in San Francisco will collapse during an earthquake?
10%
What is 1 degree equivalent to (latitude and longitude)?
100 km
How many stations are across Japan?
100+
How many seismic stations are in the Western US?
1000
Each step in magnitude means ____ more shaking and ____ more energy.
10x; 32x
How many big earthquakes have been caused by the Hayward earthquake?
11 (all estimated to be equal or greater than M 6.3)
How long did it take for the computer to run data (earthquake early warning system)?
11 seconds
Earth's Diameter
12,756 km
How many stations do the Global Digital Seismic Network have?
128
How many plates are there on Earth?
15, but this is debatable. There could be smaller plates, so there's no fixed number (15+).
How long is the Hayward Fault overdue?
152+ years
How many aftershocks and what magnitudes are expected after the Haywired main shock scenario?
16 aftershocks of M > 5 occur over 2 years up to 30 miles from Hayward fault
There have been no big earthquakes since ____ in Hayward, ___ years in counting.
1868; 152
When did communication research start (as a practice)?
1905
What earthquake was so large that it depleted the crust in the Bay Area?
1906 San Francisco Earthquake
Example of Earthquakes Happening Between Long Time Spans
1918 Puerto Rico Earthquake
Where was the problem of unreinforced masonry buildings recognized?
1933 Long Beach earthquake
Where have we seen the destruction of non-ductile concrete buildings?
1985 Earthquake in Mexico
What earthquakes are in the Earthquake Quartet piece?
1992 M 7.3 Landers Earthquake (Parkfield, CA)
What event debunked the myth that all injuries are from collapsing buildings?
1994 6.7 Northridge Earthquake where 55% of injuries are caused by falling objects
Example of Reverse and Thrust Fault
1999 Chi Chi Earthquake in Taiwan
Last Earthquake in Turkey
1999 Izmit Earthquake
When did earthquake activity become more quiet in the Bay Area?
After 1800s
When did the seismicity rate drop in California?
After 1906
What can we find out if we knew accurate rates of plate tectonics?
Age of magnetic lineations
Parkfield City
Aka Earthquake capital of the world
How many instruments do good instruments have?
All 3 instruments (1 vertical, 2 horizontal)
What is the focal mechanism for an explosive source?
All black beach ball diagram (moment tensor)
Example of Fault System
All fault zones in CA make up the San Andreas fault system.
The Global WWSSN
Allowed global mapping of earthquakes for the first time
What is an earthquake early warning system useful for?
Allows people to have time to protect themselves before earthquake strikes
How do seismic waves propagate?
Along Earth on curved path
Where do earthquakes rupture?
Along a fault
What makes intensity of shaking differ?
Amplification
Stereonet
An app that measures strike and slip
Ingredient 1
An earthquake w/ more to come
Studying Human Behavior In Earthquake Drill: A Conducted National Drill
An example of observational participatory science
Dip Angle
Angle between a vertical line down the face of surface and horizontal
Why do people think animals can predict earthquakes?
Animals are more sensitive and can feel p-wave arriving quicker than humans.
What did the two earthquakes (east vs. west coast) reveal?
Area/intensity of shaking is stronger in the East bc rocks in Central/East USA are older. CA rock is young tectonic rock.
Where will evacuation from a tsunami be challenging?
Areas w/ limited access and dependent care populations
Observational research has a long history of...
Anthropology and sociology
Step 4: Identify Building's Potential Weaknesses and Fix Them (7 Steps to Earthquake Safety)
Applicable for: - If you live in condos or apartment - If you're a renter
Garrison Act
Applied Field Act standards to both existing and new schools
Temporal Correlation: Characteristics of Induced Earthquakes
Are earthquakes close in time to some human activity?
Why does New Zealand have lots of earthquakes?
Australian plates are subducting under southern New Zealand (the pacific plate under northern New Zealand).
What did the 2004 M 9.1 Sumatra earthquake and tsunami teach us?
Awareness and planning make a difference.
How does seismic energy travel?
Away from the earthquake
1933 Field Act
Banned unreinforced masonry construction for new schools
How are building codes developed/updated over time?
Based on experience
Latter Part of Earthquake Quartet
Based on idea that society and culture, including music, takes place w/ the earthquakes as an often ignored backdrop
Step 1: Identify potential hazards in your room and home and begin to fix them. (7 Steps to Earthquake Safety)
Be aware of: - Hanging objects - Objects on open shelves and tabletops - Furniture and home electronics - Water and gas pipes
How can we improve earthquake messaging?
Be more inclusive of different needs and communities.
Foot Wall
Below fault
Where did the San Andreas Fault form?
Between Pacific and North American plate over the last 15 years
At which performance levels are most codes currently in?
Between life safety and damage control
What only matters when analyzing past earthquakes?
Big earthquakes
What type of waves are P and S waves?
Body waves
Divergent Plate Boundary
Boundary between tectonic plates in which the two plates move away from each other, and new crust is created between them
Transform Plate Boundary
Boundary between two plates that are sliding past each other horizontally
Masonry bricks and mortar are...
Brittle
Color Code for Lawson Map (from Strongest Shaking to Weaker Shaking)
Brown, blue, green, pink, yellow
Where does most economic value lie in?
Buildings
Soft Story Buildings
Buildings with weak first floors that are not strong enough to support heavier second floors
What happens to the tsunami deposit?
Buried beneath young soil and tidal mud flat
At what rate can early warning reduce injuries?
By 50%
What state has the highest probability to experience an earthquake?
California
Where do most observations of hydraulic fracking earthquakes come from?
California (Santa Maria Basin)
Public Education
Campaigns to educate public about risk and emergency preparedness
Is preparedness a discourse for the privileged?
Can be limited by economic struggle
How are trenches useful?
Can learn about past earthquakes
How accurate are handheld devices when measuring plate tectonics?
Can measure precision to within a few mm
Puerto Rico is near the _____ plate.
Caribbean Plate
In what regions do San Andreas stretch between?
Cascadia to Gulf of California
What is the early origin of earthquakes for Japan?
Catfish waking up
What does orange circles mean on the Google Earth file?
Earthquakes are within upper 30 or 50 km (~20 miles) in upper most crust
Where is the earthquake rate low during the period between 1990 and 2010?
Central U.S.
What does the Pandemic and All-Hazards Preparedness Act (PAHPA) law centralize on?
Centralizes federal responsibilities and requires state-based accountability for response to earthquake and tsunami, hurricanes, flooding, wildfires, terrorism-related events, and disease outbreaks?
How can earthquakes cause disease outbreaks?
Change in condition of communities (ex. sanitation)
Who proposed that we should have a magnitude scale?
Charles Richter
Where was the 1906 San Francisco earthquake recorded?
Cheltenham, Maryland
Waves traveling through ________ are traveling _____ and so they ____ more energy and more high frequencies.
Chewed up rocks; further; lose
What happened 10 months later after the 2010 earthquake in Haiti?
Cholera outbreak (epidemic)
Why do seismic waves travel a curving path in the mantle?
Earth has a composition, density, and temperature change that causes seismic waves to refract as velocity in mantle increases w/ depth.
Blue Waves (Princeton Model)
Earth moves down.
Red Waves (Princeton Model)
Earth moves up.
How did the Sumatra earthquake impact Earth's orientation?
Earth wobbled by 2 cm, but it was still pushed off balance.
Induced Earthquake
Earthquake caused by human activity
How does social distancing (reduction in seismic noice) affect earthquake monitoring?
Earthquake detectors can detect more earthquake aftershocks clearly.
What can protect you from tsunamis?
Cliffs
High Frequency
Closer
Lesson Six from Research: Risk and Communication
Communicate the risk and hazard. Give different publics immediate actions they can take to improve their future situation.
Public Information
Communication in times of crisis
Lesson Four from Research: Risk and Communication
Comparing risks and showing them that they've accepted similar risk sin the past is shown to be ineffective. It doesn't work in persuasion bc the outrage that people feel towards the hazard IS the problem.
What instrument does geologists use to measure strike and slip?
Compass
Mapping Surface Deformation to Fault Creep: Output
Computer model of where fault creeps and where it's locked at surface and deep
Where does the San Andreas Fault connect?
Connects 2 ridges in offshore Oregon and gulf of CA
Step 7: When Safe, Continue Following Disaster Plan (7 Steps to Earthquake Safety)
Consider: - Days following earthquake - Taking action to recover
Step 2: Create a Disaster Preparedness Plan (7 Steps to Earthquake Safety)
Consider: - Places to meet after a disaster - What to do after determining meeting places - Learn lifesaving actions - Staying informed
Step 5: Protect Yourself During an Earthquake (7 Steps to Earthquake Safety)
Consider: - What are the hazards indoors? - What are the hazards outdoors? - When driving, what are the hazards?
Aesthenosphere
Consists of rock that can flow slowly; not magma
3 Stars (Building Rating System)
Constructed to current code
Opportunity (Pandemic)
Contact rate or the # of people/surfaces you came in contact with
What boundary are we on?
Continental transform boundary
Plates move closer through ____.
Continuous subduction
What do we want lab experiments to be when understanding earthquake cycles?
Controllable
What drives plate tectonics?
Convection
Lake Level Changes in Azle, Texas
Correlation exists between lake level and earthquake.
Process of Hydraulic Fracturing
Creating additional fractures in rock to extract oil
Racking
Cripple walls buckle and collapse.
Memorial Stadium
Cut by the fault and creeping from Hayward Fault
Hazard Reduction: MyShake
Earthquake early warning
Shake Alert
Earthquake early warning system
We use slip rate to calculate ______.
Earthquake occurrence
How did decrease in oil prices impact induced earthquakes?
Earthquake rate has decreased.
What does refraction of P and S waves show?
Deep layered earth's structure
Relationship Between Trenches and Earthquakes
Deepest trenches relate to the biggest earthquakes.
Giuseppe Mercalli (1850-1914)
Developed the Mercalli Intensity Scale to observe damage to buildings in Southern Italy
Why were there induced earthquakes in Johannesburg, South Africa
Did gold mining within city limits (room and pillar mining) that caused slips on faults within mines (felt at surface)
What's significant about the earthquake in Puerto Rico?
Didn't happen on plate boundary fault but convergence occurs
What do slower regions indicate for seismic waves?
Different material than the surroundings (anomaly)
Rocks vs. Temperature vs. Velocities
Different rocks at different temperatures will have different velocities.
How soon should we expect the next big earthquake on the Hayward Fault?
Difficult to determine
What is used to create a beach ball diagram?
Direction of first motion of seismic waveforms around the globe
Fault Creep
Displacement along a fault that is so slow and gradual that little seismic activity occurs; doesn't cause earthquake
Slip Rate
Displacement/time
You need ____ to determine S-P times.
Distance
What is a direct measure of distance?
Distance in arrival time (S-P)
Calculating Velocity
Distance/Time
There's a direct relationship between ____ and ____.
Distance; arrival
What is critical to good science?
Diversity
Earthquake Drill
Drop, cover, hold
Wood beams are...
Ductile
Ductile Deformation
Ductile materials undergo smooth, continuous plastic deformation and do not spring back to their original shape when deforming face is released
What can a GPS calculate?
Each station's velocities
Initial Section of Earthquake Quartet
Embodied earthquake cycle
Pandemic and All-Hazards Preparedness Act (PAHPA)
Enacted in 2006 by President George W. Bush to improve the nation's ability to detect, prepare for, and respond to a variety of public health emergencies.
What do waves lose as they travel?
Energy
What does moment magnitude relate to?
Energy of earthquake
Waves
Energy propagating w/ time
Reduced Vulnerability: Denali Earthqauke
Engineered for 8 meters of slip
What is the center of a beach ball diagram called?
Epicenter
Little vs. Big Earthquakes
Even when you add together the energy release from all the small earthquakes, it's still small compared to the one big event due to the factor of each magnitude.
How often are Bay Area earthquake probabilities updated?
Every 10 years
Where do earthquake cycles occur
Everywhere (mostly Western U.S.)
What does the black shading on a beach ball diagram reveal?
First motion (up vs. down or push vs. pull)
Polarstem
Flagship of German Polar research Alfred Wegener institute
Lowering reproductivity Rₒ is the same as...
Flattening the curve (lowering risk)
A strike slip earthquake isn't capable of making a large tsunami if they're producing...
Horizontal motion
Wilson's Theory on Hotspots
Hot spot, oceanic islands sets over plume of rising mantle, making magma, and building up an island
What broke up the Farallon Plate?
Hot spots
What is Yellowstone underlain by?
Hot spots that left a 16 million year old track as plate moved above it
Overturning
House lifts off foundation.
Sliding
House slides off foundation.
5 Stars (Building Rating System)
Expected to be usable after largest probably earthquake
How much smaller would the amplitude be if earthquake was 1 magnitude unit smaller?
Factor of 1/10
How much smaller would the amplitude be if earthquake was 2 magnitude units smaller?
Factor of 1/100
Where do most hazards in earthquakes come from?
Falling hazards
All waves have same types of particle motion. (T/F)
False
Cascadia is below the subduction zone. (T/F)
False
Continents are younger than the ocean. (T/F)
False
During an earthquake, head for the doorway. (T/F)
False
Each type of wave have the same propagation velocities. (T/F)
False
Earthquakes cannot impact mobile homes. (T/F)
False
Earthquakes cannot interact with each other. (T/F)
False
Elastic rebound theory explains ALL faults. (T/F)
False
For earthquake forecasting, the farther out time we go, the mpre confident we are. (T/F)
False
Hydraulic fracturing causes earthquakes. (T/F)
False
Most plate boundaries are perfectly translational, compressional, or extensional. (T/F)
False
Not all earthquakes have aftershocks. (T/F)
False
The 1906 San Francisco earthquake did not produce a tsunami. (T/F)
False
There are no faults in Oklahoma. (T/F)
False
There has been proper evidence or documentation of the release of radon gas. (T/F)
False
There have been reliable precursors for predicting earthquakes. (T/F)
False
There's no uncertainty in earthquake forecasting. (T/F)
False
We can limit to main boundaries when predicting earthquakes. (T/F)
False
What did the Rangely Experiment hypothesize?
Fluid pressure causes earthquakes. Hypothesis was proven correct.
How does injection cause earthquakes?
Fluid releases stress on fault.
Fastest Ray
Follows deeper path that refract
You can't tell if an earthquake is a _____ until there's a ______.
Foreshock; main shock
After Slip
Form of accelerated creep
What is the early origin of earthquakes for China?
Frogs
How do we create topography?
From seeing movement of dip slips like mountains
How has drilling changed?
From vertical to horizontal drilling
Immanuel Kant (1724-1804)
Gave first rational, enlightened explanation of the catastrophic quake
Your phone can be a _____.
Geological compass
What is crucial for measuring earthquakes?
Global Observations System (network of seismometers)
Key Takeaway of the Parkfield Experiment
Good data can't always predict earthquake.
Ground Uplift and Tilt
Gradual ground elevation and subsidence over decades
What influenced Japan to establish building codes in 1923?
Great Kanto earthquake led to these efforts.
The largest tsunami wave wouldn't be higher than...
Half a meter
What can also be used to find changes in plate tectonics?
Handheld devices (accurate of several meters)
When do precursory stages occur?
Happens on short time scale (hours/day)
Tsu
Harbor
How do you determine magnitude on a nonogram?
Has a nonlinear logarithmic scale of amplitude (measured on Wood Anderson Seismometer) and a scale of distance (S-P) that allows you to determine a magnitude by connecting 2 dots
Example of a Hot Spot
Hawaii's chain of islands
Haywired
Hayward Fault (Northern California) earthquake scenario
The probability of an event on _____ is higher than _____.
Hayward; San Andreas
Which scenario is currently in progress?
Haywired
Nature presents us with ____ and we cannot control it.
Hazard
Earthquake probability estimates are long term assessments of...
Hazard and risk
Primordial Heat
Heat that was produced as Earth formed 4.5 million years ago
Seismic tomography...
Helps take x-ray of the Earth
What does a sharp jolt mean in terms of frequency?
High frequency
What is the biggest vulnerability in San Francisco during earthquakes?
High rises
Transmissibility (Pandemic)
How close you get and how long you're near infected host
What does time measurements between P and S waves reveal?
How far away the earthquake is from the station
What helps seismologists measure size of an earthquake?
How long fault slips during earthquake
What does seismic tomography measure?
How slow and fast seismic waves are
Peak Acceleration
How sudden an object gets accelerated against gravitational attraction
What was incorrect about Wegener's theory of continental drift?
How the continents moved away from each other
What would we not know without GPS?
How the earth moves
Which process can extract more oil and gas?
Hydraulic fracturing
What are we seeing more of, especially Oklahoma?
Hydraulic fracturing induced seismicity (correlated w/ hydraulic fracking stimulation)
Where is an earthquake initiated?
Hypocenter
Where do earthquakes start?
Hypocenter (focus below the epicenter)
What software can detect creep along faults?
INSAR
When is a fault considered a thrust fault?
If it's shallower than 45 degrees
In what circumstance should you NOT evacuate your home after an earthquake?
If only utilities are off
In what circumstance should you turn off the gas after an earthquake?
If there's a leak
What is the challenge with risk?
If we can implement strategies to reduce risk
How can we statistically assess earthquake probability?
If we know - Where we are in earthquake cycle (how long it's been since the last big earthquake on any particular segment) - Times of last big earthquake (average recurrence levels and variation)
Main Shock vs. Aftershock
If you have a M7 main shock, your aftershock would be M6.
Which performance level is our goal for most codes to be in?
Immediate occupancy
What does the SAFRR Tsunami scenario examine?
Impacts on coastal residents, visitors, infrastructure, economy, and natural environment
What is the solution to the cholera outbreak in Haiti?
Improve water and sanitation infrastructure
The Parkfield Prediction Experiment
In 1984, USGS and Berkeley researchers predicted an earthquake at Parkfield in January 1988 +/- 5 years
Example of Demonstration Project Partnership
In 2012, BART developed initiated an automatic train stop to automatically slow down trains.
How do seismic waves travel in the mantle?
In a curving path
Locked Fault
In position until earthquake
Joint Model
Includes a geodetic and seismic model (displacement and shaking)
P waves reveal...
Info of geometry of fault plane
Model of Communication
Info source (message) ➝ transmitter (signal) ➝ noise source (received signal) ➝ receiver (how receiver understands signal) ➝ destination (message)
Enhanced Oil Recovery
Injection of fluid back into production formation
There's a connection between _____ wells and _____.
Injection; earthquakes
What did Charles Richter argue?
Intensity affecting a particular point of observation doesn't allow us to describe size of earthquake.
What did the Lawson Report reveal?
Intensity of 1906 San Francisco earthquake based on indirect measures
How was the sediment dated in the ghost forest?
Isotopic method (Carbon 14)
What's wrong with San Francisco's building code?
It doesn't protect cities from earthquakes.
Why is horizontal drilling more effective than vertical drilling?
It extracts larger oil and produces 10x more water than in vertical drilling.
Any wave will refract if...
It goes into material with different velocities (view drawing in notebook)
What happened to the hospital in Sylmar, CA after the 1971 6.7M San Fernando earthquake?
It had to be demolished.
Why does the mid-atlantic ridge have shallow earthquakes?
It is where things are the hottest.
How strong was the Sumatra earthquake?
It released energy of 23k Hiroshima bombs.
What happens to the plate boundary when an earthquake happens?
It slips. Sea floor rises and tsunami waves spread out from bulge (then tsunami occurs).
How did the normal fault get its name?
It was the most common fault movement to occur during period of experimentation.
Why is the Bay Area considered the "prisoner of plate boundary?"
It's between the Pacific and North American plate.
What is wrong with the Millennium tower in San Francisco?
It's leaning and sinking an inch per year.
What happens to the S wave as distance increases?
Its arrival increases or takes longer (since S wave arrives after P wave).
Origins of Earthquake Early Warning
J.D. Cooper proposed earthquake early warning system in San Francisco 1868 (the use of modern technology to predict earthquakes). Features: - Wanted detectors outside of city - Use of telegraph wires - Earthquake bell - Automated - Will work for distant shocks
What did USGS and Berkeley researchers predict for the next Parkfield earthquake?
January 1988 +/- 5 years
What was the second place to have an earthquake early warning system?
Japan
Which country has the best GPS network in the world?
Japan
Example of Public Education
Japan made infographics regarding Do's and Don'ts of earthquake early warning (what to do in different scenarios)
What is the Great Shakeout Earthquake Drill based on?
Japan's September 1 Earthquake Day
Which country spends the most on earthquake research?
Japn
Where did the first known induced earthquake occur?
Johannesburg, South Africa
Where have induced earthquakes have been going on for 100 years?
Johannesburg, South Africa
Lesson Nine from Research: Risk and Communication
Keeping people "out" is not the solution. Mistakes are... - Controlling information - Purposefully not inviting challenging groups to conversations - Not acknowledging other people's POV - Determine priorities based on your own POV
What earthquake influenced Japan to develop an earthquake early warning system?
Kobe earthquake (1995) that killed 6000 people
What will happen to LA in 9 million years?
LA will go offshore (assuming San Andreas moves fast as it goes today).
What type of experiments are used to understand earthquake cycles?
Lab experiments
Electrical Conductivity
Lab experiments show that water saturated and granite changes resistivity before fracturing.
Bathymetry showed no evidence of ____.
Land bridges
What type of earthquakes leave the biggest data?
Large earthquakes
Fault Zone
Larger fault made up of smaller faults
Why is Browning's theory incorrect?
Last planetary alignment was in 1982 when there were predictions of many earthquakes in CA (nothing unusual happened. - Previous peaks were 1803, 1624, and 1445 (nothing happened)
What was the result of magnetic fields flipping?
Left North, South, East, West imprints
X-axis
Left and right
A fault that goes up and down is...
Left lateral
Duration (Pandemic)
Length of infectious period
Richter Magnitude
Magnitude is log10 of the maximum amplitude recorded on a Wood-Anderson seismometer at 100 km from the epicenter
The bigger the ___, the bigger the ___.
Magnitude; energy
What's crucial about performance levels?
Levels are lessons learned from earlier disaster.
Susceptibility
Likeliness of getting sick
What is the earth's core comprised of?
Liquid
What happens to topography if you get a perfectly strike slip movement?
Little topography
What does P wave arrival time tell us (earthquake early warning system)?
Location
Faults can be ___ and/or ____.
Locked; creeping
The Hayward fault is partially ____ and _____.
Locked; creeping
Big earthquakes happen between ____ time spans.
Long
Clue #1: Ring of Fire (Pacific Northwest)
Long recognized that earthquakes and volcanic eruptions occur around Pacific Rim
Earthquake Forecasting
Long term process to estimate probability of earthquake and their hazards
How did seismologists in Haicheng, China predict the earthquake?
Looked at frequency of foreshock and saw uptake of small earthquakes before main shock
Social Norming and Milling
Looking at others to see what they would do
1 Star (Building Rating System)
Loss of life probable
What does a rolling motion mean in terms of frequency?
Low frequency
What type of frequency shaking dominates what you feel the farther you are from an earthquake?
Low frequency shaking
What does green mean on an earthquake probability map?
Low probability of shaking
What was the largest induced earthquake in Azle, Texas?
M 3.6
What's the largest earthquake caused by enhanced oil recovery?
M 4.5
Borrego Springs Earthquake (2016)
M 5.2
What is the largest earthquake caused by fracking?
M 5.7
What's the largest earthquake caused by hydraulic fracturing?
M 5.7 in China
What is the largest earthquake caused by wastewater injection?
M 5.8
What's the largest earthquake caused by wastewater disposal?
M 5.8 in Pawnee, OK
The DC Quake (Aug 23, 2011)
M 5.9
Napa Quake
M 6.0
What's the largest earthquake caused by oil production?
M7 in late 1970s and 1980s in Ubekistan
What repeating cycle does the Cascadia subduction zone have?
M8 and M9 earthquakes
Conrad Röntgen
Made the first x-ray
Rocks on the ocean sea floor are ___.
Magnetic
What does P wave amplitude tell us (earthquake early warning system)?
Magnitude
What does seismic moment get converted into in Moment Magnitude Scale?
Magnitude
Why can't people work with emergency managers?
Managers always create complicated charts w/ acronyms.
The Lawson Report
Mapped distribution of shaking from 1906 San Francisco earthquake as it impacted houses and other features
What do early studies of communication focus on?
Mass communication now shifting to mass self-communication (ex. social media)
Wood Anderson Seismometer
Measured Richter Magnitude
What does peak acceleration and peak velocity represent?
Measurement/observations of intensity of shaking at seismic station
What is a part of public relations?
Media relations
What was the first place to have an earthquake early warning system?
Mexico City
When was the idea of plate tectonics finally accepted?
Mid to late 1960s, early 1970s
Example of Divergent Plate Boundary
Mid-ocean ridges
Formula for Seismic Movement (Mo)
Mo = δ x L*W*D - L*W*D is where you multiply the area of the fault's rupture by the average slip on fault. - δ is the shear modulus (different notationl in notebook)
Example of Normal Fault
Moab Fault in Utah
Earthquake Early Warning Systems
Modern seismic networks fast enough to gather and process earthquake data and sends alert to EEW users before shaking arrives
What can increased seismicity lead to?
More seismicity
How many stations were set up by WWSSN by the 1920s?
More than 100
Order of Wave Arrival
P wave → S wave → Surface waves OR P wave → S wave → Love wave → Rayleigh wave
Lesson Three from Research: Risk and Communication
Most publics don't respond to numbers alone. This isn't a matter of getting the number's right and simply telling them the numbers.
Single Family Homes
Mostly wood frame in California (which are good places to be in an earthquake)
Creeping Fault
Move a little every year
Left Lateral Fault (Transform)
Moves to left
Right Lateral Fault (Transform)
Moves to right
Transdisciplinary
Multi-research disciplines combined w/ knowledge of practitioners
USA is a _____ nation.
Multihazard
Moment Magnitude Scale Formula
Mw = (log Mo - _____)/_____ where Mo is the seismic moment in Newton meters
What app can act as a seismograph?
MyShake
Normal Magnetic Polarity
N S
Atmospheric Rivers (AR)
Narrow regions in atmosphere responsible for horizontal transport of water vapor outside of the tropics
The San Andreas Fault is described as...
Narrow w/ repeated slip
Trenches
Narrow, skinny features, deepest parts of the ocean
What evidence proved ghost forest, Cascadia earthquake, and tsunami?
Native American ancestral stories
What did Voltaire argue about regarding All Saint's Day
Natural causes, not god's doing.
Hypocenter
Near bottom of rupture
Where did the Sumatra earthquake take place?
Near see bed (300 km deep)
Where is the highest shaking often located?
Near the fault
What criteria is needed for an earthquake early warning system to be useful?
Need multiple stations to get a reasonable location and more detail about earthquake
Who should you contact if you decide evacuate?
Neighbor or out-of-town contact
What primary sources help measure intensity of an earthquake?
Newspaper articles
Where was ground uplift and tilt observed?
Nigata (1964)
What is true about deep in the U.S. and plate boundaries?
No plate boundary deep in the U.S. but some earthquakes still occurs every so often
What wasn't observed in Parkfield experiment?
No precursory signals
Can animals predict earthquakes?
No single study shows animals can predict earthquakes?
Do waves follow by strength?
No. For example, if three waves came, the would not arrive in a specific order like strongest to weakest. The strength of waves are not sequential.
What type of damage has limited retrofit program and why?
Non-ductile concrete buildings bc it's most costly
What type of faults have the same 45 degree dip?
Normal and reverse faults
In which direction is the Pacific Plate moving?
North relative to North American plate
Which region was the first to experience the tsunami from the Sumatra earthquake?
Northern Sumatra
Lesson Seven from Research: Risk and Communication
Not addressing realistic concerns from people.
What happened on December 3 (predicted earthquake date)?
Nothing.
How is radon gas formed?
Nuclear fission of some radioactive minerals in the ground
Hayward has highest _____.
Nucleation probability
What waves propagate faster than the other?
P waves propagate faster than the S wave.
What waves can travel in liquid outer core?
P waves, not S waves.
Sue Nami
PSA for tsunami awareness
Where can you encounter surface rupture?
Paleoseismic trenches
What was correct about Wegener's theory of continental drift?
Pangaea
Why are tsunamis produced?
Part of the fault that is stuck in years between earthquakes slowly deform as plates keep converging and producing strain.
What to Expect After Next Quake (Observed Building Failure Modes): Soft-Story Buildings
Partial collapse
What were initial building codes based on?
Observed damage in quakes
Earthquake Precursors
Occurs before each large earthquake
What do the crosses on the map mean (mid-oceanic ridges)?
Oceanic crust is being created and moving away from ridge.
Subduction Slab
Oceanic crust which descends into the mantle
South America (Convergent Plate Boundary)
Oceanic plate going below continent (subduction zone) back into mantle
Vulnerability: Denali Earthquake
Oil pipeline subject to damage and leak
How can we predict ground shaking for earthquake early warning?
Once an earthquake has started/nucleated
Data Latency and Network Status
Once p-wave is released, information gets to a station within a second.
How many measurable precursors (observations) do you need (minimum) to predict an earthquake?
One
What does the simplest seismograph have?
Only one instrument (vertical)
Early Origins of Earthquakes: PNW
Oral traditions (1700)
What do beach ball mechanisms help us learn?
Orientation of faults
Where does an earthquake propagate?
Outward at hypocenter
Where does the slip area propagate?
Outward from hypocenter on fault plane that lies below eicenter
What wave goes through outer liquid core?
P wave
Order of Wave Arrival
P wave before S wave before love wave before rayleigh wave
What is the hazard during a pandemic?
Pathogen (virus, bacteria, etc)
Example of Charlatan in Context of Earthquake Prediction
People believe they can predict earthquakes even though they have no credibility.
What was the main reason for people not participating in the earthquake drill observational study?
People were reluctant or embarassed.
What does the color scheme on ShakeMap categorize?
Perceived shaking and damage
Charlatans
Person falsely claiming to have special knowledge or skill
The Roots of Communication
Philosophy, ethics, sociology, psychology, political science, anthropology, marketing
How did engineers modify Trans-Alaska Oil Pipeline (TAPS) for an earthquake?
Pipeline (where it crosses Denali Fault) was put on slider beams, so it can deform if earthquake occurs.
What did magnetic stripes reveal?
Plate age
What goes into an earthquake cycle?
Plate boundary stress
Bottom Drag
Plate dragged by convection in mantle
Plate Tectonic vs. Fault vs. Earthquake
Plate tectonics make faults, faults create earthquakes.
Why do plates that get pulled down into subduction can still make plates?
Plates are very cold.
Plate Tectonic Theory
Plates separated by opening crust and pushing magma
What can improve firefighting water supply?
Portable water supply systems
Why were there earthquakes near Azle, Texas?
Possibilities: - Natural earthquake activity - Water level changes in Eagle Mountain Lake - Water table decline due to prolonged drought - Production from Barnett - Waste water disposal
Ingredient 3
Possibility that prediction of earthquake is possible and true
Downtime of Life Safety: Performance Level
Possible total loss
4 satellite signals _____.
Provide latitude, longitude, and elevation
3 satellite signals _____.
Provide longitude and latitude
Tsunami Walk
Public event staging a walk to safer higher ground
Initial Dilation (-) on Nodal Plane
Pull (not shaded)
Initial Compression (+) on Nodal Plane
Push (shaded)
Red Tag
Put on homes to indicate that the property is unsafe and must not be entered/occupied after an earthquake
Process of Discovering Earthquake Early Warning System
Questions to consider: 1. How quickly can we detect and characterize an earthquake? 2. Is the available warning time useful? For what? 3. Who should/will fund a warning system? What will it cost? 4. How do we educate people to use the system?
How does a GPS obtain your location?
Ranging
Early Origins of Earthquakes: China
Records from 780 BC
Early Origins of Earthquakes: California
Records from mid 1800s
Hog Lake: San Jacinto Fault
Records rupture and folding
How can you reduce risk?
Reduce vulnerability (ex. reducing vulnerability of infrastructure)
What does it mean when racks form?
Reducing seismic velocity
Waves get more complicated as they...
Refract in crust and mantle
Seismic waves are being _____ (bent in Earth) as they encounter _____.
Refracted; different rocks w/ different velocities
The Blind Zone
Region close to epicenter where telemetry and processing delays prevent warning
What did the Ridgecrest earthquake (2019) reveal about buildings?
Reinforced buildings continued to experience damage
Plate velocities are ____.
Relative and absolute
Why are there always 2 lines in the beach ball diagram?
Seismologists don't know which of the 2 possible orientations that are 90 degree away from each other is actually the fault they measure.
Quasi-periodic Earthquake Occurrence
Semi-regular and has significant variability
North America and Europe Separation
Separated by 2 meters in a lifetime
What does each earthquake scenario come with?
ShakeMap
What is the consequence of the slip in the fault?
Shaking
What type of waves can't propagate in fluid?
Shear waves
For the same magnitude, a ____ fault will produce higher frequencies than a ____ fault.
Short; longer
Geodetic Model
Shows displacement
Tsunami Model
Shows ocean waves
Seismic Model
Shows seismic shaking
Teleseismic Model
Shows teleseismic waves
How do silver bullets tell us information about large earthquakes
Shows where and how big it will be
What can waves reveal?
Shows where, how, and material of rock
What is the biggest accomplishment regarding Japan's seismicity?
Since 1979, earthquakes causing 10+ fatalities have not occurred in regions forecast to have high hazard.
What is the main difference between the 1906 San Francisco earthquake and the 1868 Hayward earthquake?
Size of high intensity
What is the early origin of earthquakes for Siberia?
Sled dogs scratching themselves
Earthquake is due to _______ in Earth's crust, which relieves a condition of _____.
Slip on rupture; local elastic strain
Seismic x-ray tomography illuminate...
Slow and fast features in earth
After passing through a ____ zone, seismic waves _____.
Slow; return to their faster speed
An aftershock would be 1 magnitude unit _____ than the mainshock.
Smaller
What is always expected after an earthquake?
Smaller aftershocks
What is the early origin of earthquakes for Philippines?
Snake
Citizen Science: MyShake
Social engagement
What does the inner core of the Earth have?
Solid iron
What was used for bathymetry?
Sonar
Contra Costa Shear Zone
Source of 2015 M6 South Napa earthquake
Induced Seismicity in the U.S.
Starting in early 2005, earthquakes w/ M>3 have increased in central U.S. mainly due to wastewater injection.
Earthquake Early Warning
Station detects earthquake close to hypocenter and transmits info to warning system
Direct Ray
Stays in the lowest layer
The ____ the dip, the more ____.
Steeper; vertical
Example of Transform Plate Boundary
Strike-slip faults
What do the darker colors represent on the maps from the Lawson Report?
Stronger shaking
The Rangely Experiment
Study conducted by Jack Healy and Barry Raleigh
What is on the Juan de Fuca plate?
Subduction zone
Which fault has a more shallow dip?
Subduction zone (reverse fault)
What is happening in San Andreas?
Subduction zone keeps shrinking
Example of Convergent Plate Boundary
Subduction zones
What type of zone is the Ring of Fire?
Subduction zones
Where do the biggest earthquakes and tsunamis occur?
Subduction zones like Alaska
Implied Risk of Life
Subjective measure of the threat of life threatening injury or death that is expected
What does yellow mean on USGS Hazard Map?
Substantial seismic hazard
Mapping Surface Deformation to Fault Creep: Input
Surface deformation
Surface Rupture
Surface expression of the slip at depth that produced earthquake
Earth's crust is divided by ____ and is driven by ____.
Tectonic plates; convection
What happens as you go deeper into the Earth?
Temperature increases
What is the Elastic Rebound Theory also known as?
The Earthquake Cycle
What was the 1868 Hayward Earthquake called before the 1906 San Francisco Earthquake?
The Great San Francisco Earthquake
What plate is moving slowly than before over time and why?
The Indian plate because of continental collision
Which region has intense earthquake activity?
The Pacific Rim
Vulnerability
The assets we put in nature's way
Colluvial Wedges
The basis for defining earthquake on normal faults
Reflection
The bouncing back of a wave when it hits a surface through which it cannot pass.
What does the Elastic Rebound Theory describe?
The cyclic buildup of stresses on a fault leading to an earthquake
What did the NOVA video discuss?
The destruction of the 2004 Sumatra earthquake (M9) aka the most violent geological event in history
What does INSAR measure?
The difference in satellite ground distance between a before and after image (teleseismic shaking)
What does the epicenter usually represent on a map?
The earthquake
What would happen if an earthquake struck the Bay Area during the coronavirus pandemic?
The government is not ready for this scenario.
Rose St. and Prospect Court Intersection
The intersection and curb that showed fault creep from Hayward Fault
What did Chris Goldfinger's Turbidite record reveal overall?
The last Cascadia earthquake was in 1700.
What are aftershocks a good indicator of?
The length of fault that ruptured
What do we need to know to make seismic hazard estimates?
The magnitude earthquake a fault will produce before the earthquake
What happens to each wave the further you are from an earthquake?
The more spread out the P and S wave and love and Rayleigh waves are
What's the benefit of having many stations?
The more stations we have, the more accurate our records of seismic waves are (if they're fast or slow).
Loans
The most common form of assistance after an earthquake disaster; max $40k per home
Farallon Plate
The oceanic plate that was subducting beneath western North America
Relationship Between Building Age and Building Codes
The older the building, the less strict the building codes.
What plate are we on?
The outer layer of convecting cells
Subduction
The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary
Lesson One from Research: Risk and Communication
The public isn't lazy or uneducated. The ONE general public doesn't exist; publics do! Every "public" is different and are diverse. People are busy and have other priorities. They aren't stupid.
Earthquake
The release of built-up stress along faults
How was the Parkfield Prediction Experiment conducted?
The site was heavily instrumented to observe the earthquake process before, during, after rupture t
Paleoseismology
The study of prehistoric earthquakes
Example of Hazard (Sun Scenario)
The sun
Time Difference between P and S Wave
The time difference between P and S wave increases with distance.
Fault System
The whole plate boundary system that includes all fault zones
What factor is a core to communication research?
Theories of persuasion
Relationship between Shaking and Distance
There are areas w/ higher shaking even if they're further away bc of soft rock/loose sediment. Ex. East Coast has more intense shaking than West Coast.
What did qualitative analysis revealed in the earthquake drill study in New Zealand?
There are top reasons for not participating in the drill besides embarrassment. - Children - Busy working - Didn't take it seriously - Didn't want to - Disability - Uncertainty - Didn't believe in technique - Confusion - Anxiety - Inappropriate location - High body mass
Why are there so many earthquakes and volcanoes on the Ring of Fire?
There's a ring of subduction zones.
What has happened to earthquake readiness?
There's a significant decline at all levels (63+ million people in 2018)
Why are there always two orientations on a beach ball diagram?
There's always ambiguity on which orientation is the right one?
Velocity vs. Depth
There's an increase in velocity as a function of depth.
Why are earthquakes difficult to study in areas you don't expect to have earthquakes?
There's no seismometers, so there's no good data.
What should you put in a personal go kit?
These are recommendations: - Medicine - Insurance cards - Doctor contact info - Medical consent for for dependents - First aid kit - Spare glasses - Personal hygiene supplies - Spare shoes - Bottled water - Snacks - Whistle - Cash - ID - Emergency contact numbers - Toys (for kids) - Extra light (flashlight, matches)
What should you put in a household disaster kit?
These are recommendations: - Water (at least 1 gallon) - First aid kit - Medicine - Hygiene items (soap, toothpaste, toilet paper) - Emergency lighting (light sticks, flashlight) - Batteries - Radio - Canned food - Cooking utensils - Can opener - Extra clothes - Tent - Blanket - Work gloves - Protective goggles - Pet food - Pet restraint - Copies of important documents
Indoor Hazards: Step 5 of 7 Steps to Earthquake Preparedness
Things to Follow: - Don't stand in doorways - Don't run outside - Move away from exterior walls and windows, tall furniture, hanging pictures, and mirrors - Drop to the floor next to interior wall and cover head w/ arms if there's no table - Turn off stove if cooking - Stay put if in bed. Cover head w/ pillow. - If in high rise, stay away from windows. - Don't use elevators.
Driving Hazards: Step 5 of 7 Steps to Earthquake Preparedness
Things to Follow: - Don't stop on or under overpasses, bridges or tunnels. - Don't stop under or near electrical power lines, light post, trees, or signs - Pull to side of road and set breaks - Stay in car until shaking is over
Outdoor Hazards: Step 5 of 7 Steps to Earthquake Preparedness
Things to Follow: - Move away from buildings, power lines, trees - Be alert for falling debris - Move to higher ground to avoid tsunami (if you're at the coast)
Where does seismic energy travel?
Through Earth's interior and across its surface as several types of waves
Golbi-Altay Earthquake, Mongolia (1957)
Thrust is flat
What is the early origin of earthquakes for Cascadia?
Thunderbird and whale talking to each other
Production and Injection: Induced Earthquakes
Timing and location of seismicity matches areas of highest stress.
Purpose of Modern Seismic Networks/Stations
To determine earthquake latitude, longitude, depth, and origin
Why do modern seismic networks use many stations?
To determine earthquake latitude, longitude, depth, and origin
Purpose of Building Permit
To ensure that standards are met
Mission of SAFRR Project
To innovate the application of science to reduce risk of natural hazards for safety, security, and economic well-being of the nation
Why do we use an array of seismometers?
To map some energy in space and time
What is the goal when living with earthquakes?
To reduce risk to acceptable levels
What earthquake is a preview of things to come?
Tohoku-Oki Earthquake (2011)
Hydrogen Bomb Campaign
Told people to wash ash .off car
When did the trees die in the ghost forest?
Tree ring study showed they all died suddenly between 1699 and 1700
What process allowed maps of CA to be more accurate?
Triangulation bc it showed how ground moves
All injuries are from collapsing buildings. (T/F)
True
Areas in the Bay are at risk of a tsunami. (T/F)
True
Earthquake prediction is not possible! (T/F)
True
Earthquake size matters for intensity. (T/F)
True
Earthquakes happen in clusters sometimes. (T/F)
True
Earthquakes happen irregularly. (T/F)
True
Explosive sources can create seismic energy. (T/F)
True
For any user location in an earthquake early warning system, time until shaking and shaking intensity can be estimated. (T/F)
True
In the Bay Area earthquake history, there are more earthquakes evident in the paleoseismic record than in historical record. (T/F)
True
It is difficult to test earthquake forecasts. (T/F)
True
It's better to fine-tune probabilities than try to predict earthquakes (T/F).
True
Many communities in New Zealand developed stress and trauma from earthquake, which led to events being held outside. (T/F)
True
Most injuries in quakes are from objects that break or fall on people. (T/F)
True
Most of the U.S. is at risk of earthquakes. (T/F)
True
Past rate of recurrence makes severe flooding in the future a likely possibility, especially in a warming global climate. (T/F)
True
Seismic Hazard
What nature presents to us
What does risk depend on?
What we put in the way of the hazard
Stress Shadow
When a big earthquake happens, it resets its own clock and changes stress/adjusts clock of other faults nearby.
Slap Pull
When a dense oceanic plate sinks beneath a more buoyant plate along subduction zone, pulling the rest of plate behind it
Why do seismic and body waves refract during an earthquake?
When a large earthquake produces enough energy that seismic waves and body waves propagate into the earth, they get refracted (bc seismic velocities change).
Ridge Push
When magma rises at mid-ocean ridge and pushes oceanic plate in 2 different directions away from the ridge
What is the scientific answer for defining an earthquake?
When the ground breaks along a fault (aka seismic waves)
What is the common answer for defining an earthquake?
When the ground shakes where I am (aka seismic source)
How can we estimate shaking hazard?
When we have scenarios, we estimate ground shaking maps for each earthquake scenario. Factors include the number of faults, fault segments, and rupture scenarios.
"Did You Feel It"
Where people entered their perception of what Earth shaking is like
Under what circumstances do a large number of earthquakes usually occur?
Where there's a collision zone and a dense population
Greene Act
Which set deadlines for schools to be inspected and retrofitted/replaced if needed
Source mechanism is based on...
Which station moved up or down first
How does intensity vary?
With location, distance, sediment, and rock below
Trans-Alaska Oil Pipeline (TAPS)
World's largest privately funded construction project ($8 million) placed above ground on Denali Fault
Why is it useful to use seismic arrivals?
You can describe the geometry of earthquake deformation.
Relationship between GPS and Plate Tectonics
You can use a GPS to measure plate tectonics.
How can you create a cluster earthquake record with trenches?
You dig up evidence of past rupture in the sediment.
What's the issue with foreshocks?
You don't know a foreshock is a foreshock until you get the main shock.
How do you know if you're on a left lateral or right lateral fault plane?
You see which direction the plane in front of you is moving. Ex. If the plane in front of you is moving to the right, it's a right lateral fault.
Anything under the ocean that we can't see is ____ that _____.
Young volcanic rock; spread away from mid-ocean ridges
Vertical (Seismograph)
Z axis
(Long term build up) - (Steady slip) = (Amount left for earthquake slip)
ex. 10 mm/year - 4mm/year = 6 mm/year
Magnitude-Number (Guttenbirg-Richter) Relation
logN = a-bM N = number of earthquakes M = magnitude a and b = constants
Building Damage in 2017 North Bay Fires
~$10 billion
Why are magnetic fields measured as stripes?
to show periodic reversals of Earth's magnetic field
Global Average for b (Magnitude-Number Formula)
~1
Reversed Magnetic Polarity
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