GEOL 1010 FinAL
Isostatic Rebound
- crust "rebounding" into old shape/location which reroutes rivers and streams
Ice on Earth
- currently covers ~9% of Earth's land area (Antarctica - 85%, Greenland - 10%) - ice on Antarctica exceeds 4,200m (2.5mi) in thickness
How is human activity causing desertification?
- deforestation - livestock grazing leaves soil exposed and wind makes deflation occur
Why are deserts found where rain shadows occur?
- desert is on side of mtn that does not get rain (lithosphere affect) - hard to get rain/water vapor to reach center of large bodies of area (another lithosphere affect) ex: Asia
How do proxies help with recording climate?
- different proxies record different aspects of climate on different time scales ** air bubbles are NOT proxies, they are directly ancient atm ** - proxy rule: always consider nature of the proxy (ex: tree ring formation)
What is the atmospheric heat transporting process for Hadley Cells?
- done in order to redistribute excess energy at equator - heat increases so density lowers and this causes hot masses to raise higher (N or S, causes rainclouds, rainforests in tropics) - then cools enough for some to drop back down, moves towards equator - works like convection - stop at 30 degrees latitude
Plants control climate because
- draw down CO2 for photosynthesis (keeps CO2 from getting too high) - affects albedo
Transverse Dunes
- merged/long string of Barchan dunes - "wavy" appearance - in areas w/ lots of sand - wind blows in directions horn points (perpendicular to crest)
Glacier Depositional Features
- moraine - esker - drumlin - kames - kettle lakes
How is climate change causing desertification?
- more evaporation, lose water resource because of global warming
U-Shaped Valleys
- walls almost vertical, indicated glacial movement. Very distinct U shape GLACIAL EROSION FEATURE
Why are deserts found at ~30 deg latitude?
- warm air being pushed N and S of equator - air cools down at 30 deg --> this causes lack of rainfall
Basaltic magma
Most common magma that is commonly found at midocean ridge. It is about 50% SiO2 (low) and 50% other. It is very hot around 1100 Celsius and is a dry magma (not much water mixed in)
Isotope
Atom of an element with different number of neutrons in the nucleus
Continuous branch of bowen's reaction series
Minerals continue to form but as temperature decreases, chemistry changes. Plagioclase is formed starting with calcium rich, then plagioclase, then sodium rich.
Discontinuous Branch of Bowen's Reaction Series
Minerals form in step-wise fashion. They are classified by being ultramafic,mafic, intermediate and felsic which is decreasing in temperature. Going down in temperature the minerals go: Olivine- Ultramafic Pyroxene- Mafic Amphibole- Intermediate Biotite Orthoclase-Felsic Muscovite Quartz
Index minerals
Minerals with narrow press and temp range used to determine grade of rock. (ex: flourite only forms in low grade of metamorphism)
Sedimentary rocks
Most common rock on Earth. Contain all oil and natural gas resources. Fossils are sedimentary rocks. Different types are: clastic, biogenic, and chemical
Laccolith
pimple shape where rising magma gets stuck and warps layer of rock above it. Can be exposed on Earth's surface
Barchan Dunes
- "generic" dune - crescent or "C" shape from above view - ends=horns (lower elevation) - horns point in direction wind blows towards (wind and horns point in same direction) - sand pile near horns is thing
Anthropogenic
- "human created"
Thermohaline Circulation
- "moving hot salty water through oceans" - largest current connecting all ocean basins - when warm water hits north it gets colder and saltier so it gets denser and sinks down back in position.
Arches
- "natural bridges" - result of localized erosion - desert feature - Arches Natl. Park (UT) is 200+ arches
How does the atmosphere control climate?
- Albedo
Stable Carbon Isotopes
- C14/C12 ***** - does not give temp, gives "snapshot" of environment (general climate) - both isotopes form CO2 in atmosphere - plants take in both types of CO2 - this ratio in each plant depends on how plant goes through photosynthesis (C3 and C4 plants)
GW Myth: "The planet is burning up"
- consider how data is presented (red color indicates "red alert") - map projections also differ (2D map causes continents to stretch out and appear larger, displaying larger problem area)
Why do we care about deserts?
- cover extensive areas and are growing/expanding - 20% of land is desert - another 15% is semi-arid -problem is that deserts are not good for life
Albedo
- measure of energy reflected from material - in atmosphere
High Obliquity Angle
- completely "rocked" back - high seasonal contrast
Climate on earth is...
- complicated, not simple - varies in different parts of the earth
Precession
- Milankovitch cycle - 3-D "wobbling" motion, tilted earth rotating around straight, vertical line (creates circle) - takes ~ 11k years to get 1/2 way through cycle (1/2 way is when seasons flip months, full cycle ~ 22k yrs) -like a top
Eccentricity
- Milankovitch cycle - looks at shapes of earths orbit - Max is oval shaped min is circular shaped - switches back and forth from eccentricity min and max ~ every 50,000 years - cycle is 100,000 years. Has impact on when ice age occurs
Obliquity (tilt)
- Milankovitch cycle - tilt of earth on its axis - "rocks" back and forth by 2 degrees - cycle is ca 41k years (takes ~ 20k yrs to "rock back") *(where season are on planet)*
What is the difference between Moutonee and Drumlins?
- Moutonees are EROSIVE features (solid rock) - Drumlins are DEPOSITIONAL features (pile of sediment) GLACIAL DEPOSITIONAL FEATURE
What kind of feedback loop does Thermohaline Circulation have?
- Negative feedback loop --> will not be a runaway train, will be balanced
Atmo-Composition gasses
- Nitrogen, 78% - Oxygen, 21% - rest is greenhouse gasses: can get insolation close to surface and traps some of it
Conclusion for what is responsible for adding carbon to the atmosphere
- Seuss Effect strongly support anthropogenic hypothesis
Parabolic Dunes
- U or V shape - straighter sides than Barchan dunes - found w/ more vegetation, coastal areas - horns point against wind (point where wind came from) - vegetation is thicker towards horns so it holds sand in place. The higher elevation now moves faster than horns
Proxies
- a substitute used when we do not have originals for climate
Types of Glacial Erosion
- abrasion - plucking
El Nino Events
- affect global weather patterns - caused by changes in wind strength in equatorial Pacific Ocean
Southern Oscillation
- air pressure switching sides of water (southern b/c south of equator)
Valley Glaciers
- aka Mountain, Alpine Glaciers - glaciers fills up in valley - found almost anywhere on earth
Continental Glaciers
- aka ice sheets - dominate portion of continent and is much larger than valley glacier
Linear Dunes
- aka longitudinal dunes - long but relatively straight - crest stretches parallel to wind - wind direction varies a little -happens in areas with small sand supply
How are plate tectonics causing desertification?
- all continents line up w/ 30 deg latitude in some area or another- more evaporation, lose water resource
Hadley Cells
- atmospheric circulation cell, takes heat from equator to ~30 deg latitude
Climate
- average surface conditions over LONG time scale (min ~ 10 years, typical is 50, 100, 1000 years)
Weather
- average surface conditions over SHORT time scale (hours, days, weeks)
Firn Line
- balance (equilibrium) section of glacier in steady state
Plastic Flow
- base of glacier is at high pressure - need >50 m thickness to occur - Base of glacier moves in ductile (fluid) fashion due to high pressure - slower movement
West Pacific Warm Pool
- body of water in west Pacific water that is abnormally warm - WPWP (abbrev.)
Oxygen Isotopes
- can provide quantitative paleotemperature data - good for many invertebrate and plankton shells -Use 18O/16O ratio ex: fish bones reflect water temp when fish was alive
Milankovitch Cycles
- cause variation in insolation - 3 cycles: 1. Eccentricity 2. Obliquity (tilt) 3. Precession
Seuss Effect
- change in ratio of 14C and 12C isotopes. Decreased
How does El Nino affect other places?
- changes affect atmospheric circulation (Jet Stream) - results in widespread weather ex: during El Nino, SC has wet, cool winter and dry, warm summer
Eccentricity Minimum
- circular shape/pattern
Continental Position affects climate bc...
- climate is colder if continents are closer to N/S pole
Why do we care about the climate?
- climate is influenced by many parts of the earth
Upwelling
- cold, deep water rising to surface
Ice Cores
- drilling in glaciers - must be kept at consistent temp - ice cores from Greenland&Antarctica > 2 mi into glacier and still don't reach bottom - some cores represent > 1 million years
Why are greenhouse gasses a big deal if they are present in small amounts?
- effective at what they do - do not need large amounts to trap insolation - w/o greenhouse gasses, temp would drop by 33 degrees celsius and the earth would freeze
Eccentricity Maximum
- ellipse shape
Insolation
- energy from the sun that reaches the earth and is main energy source for the planet * "incoming" + "solar" + "radiation" * - several things affect how much insolation the earth receives. Varies based on Earth's position
What controls climate?
- energy/heat is needed to change climate
Positive Feedback
- every time cycle is completed, cycle is repeated ex: when A increases, B changes, A increases again (temp incr, ice melts, temp incr more) *doesn't always have to be increase (temp decr, ice forms, temp decr more) **hard to break out of cycle**
How do glaciers effect drinking water and irrigation?
- ex: Wash. gets ~470 billion gal/yr - melting glaciers do not provide MORE drinking water => glaciers get smaller every year so there is less and less to melt
Outwash
- fairly sorted sediment b/c glacier melts and deposits particles but water transports some particles
What is the third step in forming a glacier?
- firn = icy form of snow, denser ice than forms after granular snow
How does the cryosphere control climate?
- frozen material on Earth - ice covers ~ 9% of land surface - snow/ice albedo ~ 40-90% (reflects more, hard for temps to go up) - most land surfaces reflect ~ 15-25% of albedo
What is the fourth step in forming a glacier?
- glacial ice = even denser than regular ice
How can we record climate?
- glacial ice air bubbles - proxies
Isostatic Depression
- glaciers get so heavy that it pushes down on the crust into the mantle and it is warped. This affects layers below crust and is reason why Antarctia is 2.5km lower
GW Myth: "Scientists can't decide between global warming and cooling"
- goes back to 1975 1. NAS report - leading scientist looked @ climate change and concluded they couldn't determine what the future climate could be 2. Newsweek - "The evidence in support of global cooling has now begun to accumulate so massively that meteorologists are hard-pressed to keep up w/ it." - twisted around NAS report - consider source and check date
What is the second step in forming a glacier?
- granular snow = more compact form after snow - layers and layers building up over years
Seasonal Contrast
- how different average summer vs winter temperatures are
Glacier
- ice mass IN MOTION (min of ~50 m in thickness) - Moves because of gravity of its own weight
What does the location of the firn line tell us?
- if the glacier is advancing or retreating Retreat is when ablation takes up most of glacier and advance is vice versa
Why are the N and S poles colder than the equator?
- insolation changes with latitude - light from sun is hitting equator head on, very concentrated in a small area - light that hits poles falls over a large area - Heat must be redistrbuted because poles have a defecit of heat while equator has excess
System Interactions
- interactions among all climate-influencing components are complicated to untangle
Feedbacks
- interactions where one component changing causes other changes, then original component changes again
Finding the Carbon Source (GW)
- investigate which carbon isotopes are building up - compare C14 (radioactive) to C12 (stable) --> ratio has dropped since 1900s
What characterizes a desert?
- lack of rainfall - temperature is *NOT* a deciding factor of characterizing a desert - must be less than 10 inches of rainfall per year to be a desert
Tarns
- lakes that form at the bottom of a cirque *not present w/o glacial movement* GLACIAL EROSION FEATURE
Roche Moutonee
- large solid bedrock jutting out of ground - one side vertical, other has shallow slope - occurs from plucking *glacier was always moving toward steep side* GLACIAL EROSION FEATURE
Weathering in Deserts
- little water = little chemical weathering (rocks not breaking down by chemical weathering) - oxygen and iron oxides (make reddish color of a desert) --> is a chemical rxn (weathering w/o water) - slow weathering
Star Dunes
- looks like starfish from above - wind direction constantly changing - don't migrate much because of changing wind direction
Is the earth warming up?
- lots of places are getting warmer - majority of glaciers have gotten smaller, few have grown
Low Obliquity Angle
- low seasonal contrast
Stable Isotope Proxies
- measure as ratio (heavy/light ex: O16/O15) - diff atomic weights=diff amt of each isotope gets incorporated into molecules *key=ratio in some materials changes with climate variables -BIG NUMBER IS ALWAYS ON TOP ex: at one temp, can add ratio of O18/O16 to a growing shell, but at diff temp, need a diff ratio of O18/O16
Rain Shadows
- mountains build barrier, rain fall reaches land but cloud must move upward over mountains (to a drier land w/ no moisture) - area of land in "shadow" of mtn that gets no rainfall
Horn
- mtn peak that is unusually sharp, multiple valley glaciers carving away each side GLACIAL EROSION FEATURE
Arete
- narrow ridges that extend from horn down the mountain. GLACIAL EROSION FEATURE
Land Bridge
- narrow strip of land that connects 2 large bodies of land
What influences climate?
- oceans, plate tectonics, biosphere *not just atmosphere*
How does the biosphere control climate?
- plants - animals - biological pump
Is the GG build up anthropogenic?
- population has been rapidly increasing - supported that it may be anthropogenic
Accumulation
- portion of glacier that is growing bigger
Ablation
- portion of glacier that is melting faster than it is growing
Desertification
- process of an area becoming a desert - happening everywhere - 1 billion people in at-risk areas ex: Mid-West US, Asia, SA, Australia ex: Sahara expanding South ~30 mi/yr *alarming b/c happening quickly, makes hard to grow crops*
Ferrel Cells
- pushes heat higher than 30 deg latitude
Polar Cells
- pushes heat higher than Ferrel Cells
Animals control climate because
- release CO2 and Methane (greenhouse gasses --> heat increases)
GW Myth: "It's only 3 degrees, who cares?"
- scientists are predicting temp increase to be 3 deg C (think about units --> ~5.4 deg F) - this # is global average ex: during last Ice Age, global avg temp was ~ 4 deg C lower than today - humans can handle this change, many organisms cannot
Effects of Glaciers
- sea level change - they trap large amts of water that would be in hydrosphere if melted - melting all glaciers = sea level rise of ~65m (~200 ft, this is entire state of Florida) - since ice age sea level has risen almost 140m
How much does the obliquity angle change the insolation?
- significantly - reason why we have opposite seasons in N and S hemispheres
What is thermohaline circulation like currently?
- slowing in recent decades - does not "turn over" has quickly - b/c temps in N Atlantic have increased, water is not cooling as much - water not getting saltier b/c hot water is melting glaciers on greenland which is almost all fresh water
Kames
- small hills of sediment that often come in bunches. Represents areas where glaciers break into pieces. GLACIAL DEPOSITIONAL FEATURE
Hanging Valley
- smaller U-shaped valley "hanging" above larger valley *waterfall or water rapid is a good indicator* - Result of multiple mountain glaciers going through valley. GLACIAL EROSION FEATURE
Glacial Movement
- speed varies - center of glacier is moving faster b/c edges are in contact with rocks creating friction
What is the first step in forming a glacier?
- starts with snowflakes
8 Types of Glacial Erosive Features
- striations - U-shaped valleys - hanging valley - cirque - tarns - horn - arete - roche moutonee
Biological Pumps control climate because
- takes carbon out of atmosphere and store it temporarily in rock (lithosphere) ex: plankton take carbon out of air to make their shells, temporarily carbon is stored in biosphere, when plankton dies, shells sink as sediment to hydrosphere and carbon is locked away into lithosphere
Continental Size affects climate bc...
- the larger the continent, the more likely to be dry-desert like (especially at center) ex: Pangea **no water vapor from coasts reaches center of continents**
Striations
- thin parallel straight lines carved into bed rock, indicates area was affected by glacier GLACIAL EROSION FEATURE
What does precession affect?
- time of year *(WHEN)* you experience each season
Basal Slip
- under right conditions, can get thin layer of water at base of glacier, lubricates and reduces surface friction *rapid movement* ex: slip n slide
Erratics
- unusually large blocks of sediments dropped in the middle of nowhere by glacier
Crevasse
- upper portion of glacier than was a brittle response and forms giant cracks
What is the problem with no upwelling in El Nino events?
- upwelling is important for economy - nutrient-rich water causes best circumstances for fishing - El Nino stops fish population
Aphelion
- variation in insolation - max distance earth is from the sun so least energy * 152 million km from the sun *
Perihelion
- variation in insolation - min distance earth is from the sun so most energy * 147 million km from the sun
Loess
- very fine sediments (silt, clay) picked up by winds from outwash and tills - usually associated with good locations for agriculture - very well sorted
Till
- very poorly sorted sediment, no common grain size, in random pile because glacier melts and drops particles inside of it
What does energy react with to result in a loss of insolation?
- w/ gasses - clouds - ground surface **this totals to a loss of 30% of insolation**
Why is warm water sinking in the North Atlantic?
- warm water is cooling, getting denser - getting saltier (losing surface water to evaporation, not getting replaced, water gets denser) -blue pathway occurs on ocean floor -red pathway occurs on top of ocean
During El Nino events, what are western/eastern pacific conditions?
- western Pacific is cooler&drier, higher air pressure - eastern Pacific is warmer&wetter, lower air pressure ex: New Zealand is western Pacific ** low air pressure follows the warmer water **
What do air bubbles in glaciers tell us?
- what gasses were in atmosphere during age of glacier (and thus climate through isotope ratios) --> can date ice, ancient atm --> how much of each gas was present
Negative Feedback
- when cycle is completed, next time through cycle, opposite result occurs ex: 1-when A incr, B decr 2-when B decr, A incr (next time through) 3-A decr, B incr 4-B incr, A decr (back to step one) **creates a stabilizing see-saw effect** (neither A or B gets too high/low)
Tree Ring Proxy
- width=how much tree grew each year - close together rings means slow growing and thus bad conditions for tee. Far apart rings means fast growth and good conditions for tree.
Wind Erosion in Deserts
- wind can only move relatively small particles (clay, silt) ex: sand is too big w/o strong gusts of wind - wind has low density and low viscosity - particles > ~0.06 mm in diameter are hard to erode - can still (eventually) add up to a huge volume eroded ex: Sahara Desert - 250-500 million tons of dust are transported to Atlantic each year - Causes deflation and surface of desert to get coarser over time
Esker
- winding shape/structure (zig zag) made of out wash deposits Represents area where tunnel was going through glacier GLACIAL DEPOSITIONAL FEATURE
How much does the obliquity angle change?
- ~ 2 degrees - think of rocking chair -Max tilt is 24.5 degrees -Min tilt is 22.5 degrees
What are possible reasons for faster warming trends?
-Could be caused by increased amount of greenhouse gas build up since industrial revolution - amount of escaping insolation is decreasing
Infiltration properties
1. Porosity 2. Permeability Want both porosity and permeability to be high to use ground water
How to melt rock
1. Partial melting- rocks need ranges of temperatures to melt. In this phase it's liquid with crystal chunks 2. Wet melting- enough water drives melting point down 3. decompression melting- removing pressure makes rock easier to melt
Textures of plutonic (intrusive rocks)
1. Pegmatitic- large mineral chunks 2. Phaneritic- 1cm-1mm in size. When you look at them you see a bunch of crystals
Two types of igneous rock
1. Plutonic (intrusive) 2. Volcanic(extrusive) They are identified by how big their crystals are and what minerals are in the rock
How much rem exposure is safe
1. <5 rem a year- no problems 2. 5-20 rems: possible long term problems (like cancer) 3. 20-100 rems: mild radiation sickness 4. 200 + rems: hair loss 1/3 chance of death 5. 600+ rems: 100% fatality rate within 14 days KEEP REMS AND MREMS SEPARATE
Types of pressure
1. Confining- material is squeezed evenly in all directions. Material is not really deformed except for compaction 2. Directed (differential)- Pressure is primarily directed on two sides. Material becomes deformed.
How do plate tectonics affect climate?
1. Continental Position 2. Continental Size 3. Collision Zone Uplift 4. Land Bridges
How does the lithosphere control climate?
1. Continteal position 2. continetal size 3. Collision zone uplift 4. land bridges
Prevention of mass wasting
1. Drainage control- controls water for slope to become stable 2. Decrease slope grades 3. Building codes- determine where buildings should/not be built 4. Retaining walls 5. Rock bolts- holds slabs of rock together (expensive)
Why is the earth warming?
1. Earth is currently naturally warming - still coming out of most recent ice age (~ 10k yrs ago, blink of an eye in geol) 2. Natural Processes like changes in albedo - ex: Milankovitch cycles - account for ~50% of warming over past centuries 3. Warming is occurring faster and has a greater magnitude than other warming trends we have data for in recent history
Types of coastlines
1. Emergent Coastline- area is being uplifted so over time land is being lifted above water. Area gets steep near coast (West Coast) 2. Submergent coastline- more area is submerged underwater. Flooded/drowned appearance. Can happen when subsidence occurs or water level rises.
Advantages of fossil fuels (nonrenewable) (general)
1. Historically cheap and abundant 2. Technology is well develloped to get fossil fuels 3. Infrastructure is built to run on them
Different fossil fuels
1. Hydrocarbons 2. Coal
5 Advantages of Nuclear power
1. Large US reserve (estimated 130 year supply at current production rate) 2. Reduces carbon emissions 3. Decreases fossil fuel dependence 4. Produces tremendous amounts of energy. (1 kg of Uranium produces 3 million times more energy than 1 kg of coal) 5. good safety record
Submergent coastline features
1. Long/wide beaches and coastal plains 2. spit- body of sediment that forms narrow deposits that is still connected to shore but stretches into ocean 3. barrier islands- Long/narrow deposits of sand that are not connected to shore. Change rapidly over time.
Qualifications for a mineral
1. Nonsynthetic (naturally occuring) 2.Inorganic (no organic composition) 3. Crystalline structure (atomic structure is defined geometrically) 4. Solid 5. Set chemical composition
Consequences of Global Warming
1. Shrinking Cryosphere 2. Expanding Deserts (not hospitable for humans, no water source) 3. Rising Sea Levels (temp increase, ice melts, more water, will effect coasts) 4. More powerful hurricanes (not more, but more powerful)
What are the steps in forming a glacier?
1. Snowflakes 2. Granular Snow 3. Firn 4. Glacial Ice - all require time, cold, and precipitation (layers of all are always thawing and freezing)
Types of High Level Waste
1. Spent nuclear fuel- used up old nuclear fuel. Bi product of fission. Needs to be changed 3-4 times a year. 20 tons per years per plant 2. Trans-Uranic- Larger isotopes that is primarily generated during weapons research. Remains radioactive for longer time scale. Breaks down very slow. Must have a half life GREATER THAN 20 YEARS.
Emergent coastline features
1. Stacks- small rocky islands near coast that are very steep 2. Terrace- broad/flat areas separated by steep area. Makes a step pattern and shows beaches that were uplifted. Counting terraces tells us how many times uplift occured
What is the formation of an arch?
1. Start w/ solid body of rock w/ cracks, fractures 2. Erosion localized at fractures turn into "fingers" of rock 3. More erosion on each "finger" 4. Erosion can break down arches too and eventually collapse
What is causing desertification?
1. Tectonics 2. Climate change 3. Human activity
Impact of Theia Impact
1. The moon was formed 2. Earth was now a molten planet 3.Layers began to form
Normal Winter Conditions
1. Trade winds push warmer water west 2. the 'void' left is filled by cool water upwelling in the east 3. WPWP creates low atmospheric pressure 4. low pressure systems create lots of rain (like Hadley cells near equator) - western Pacific NORMAL conditions are warm&wet - eastern Pacific NORMAL conditions are cool&dry
Types of Proxies
1. Tree Rings 2. Biogeography 3. Stable Isotopes
What are the types of glaciers?
1. Valley Glaciers 2. Continental Glaciers
What are the 6 desert features?
1. Ventifacts 2. Alluvial Fans 3. Playa Lakes (Playas) 4. Inselbergs 5. Arches 6. Dunes
What is responsible for adding carbon (C12) to the atmosphere?
1. Volcanoes --> gives off C13 - ruled out, wrong carbon - gives off almost completely CO2 2. Deforestation = dying plants give off C12, C13, and C14 - C12 and C14 are in set ratio and cancel (hypothesis ruled out) 3. *Burning fossil fuels = almost 100% C12, no C14 (some C13)* - *only hypothesis with C12*
El Nino Winter Conditions
1. Weakening/reversal of trade winds (no strong winds) - happens in quasi-periodicity of 4-7 years - still don't know why trade winds weaken 2. Allows WPWP to migrate eastward (no upwelling) 3. Eastern waters warm, upwelling stops, lower air pressure 4. Southern Oscillation 5. Rain follows the low pressure area
Forming of sedimentary rock
1. Weathering 2. Erosion 3. Deposition 4. Lithification
High Level waste sites
1. Yucca Mountain 2. Waste Isolation pilot plant
Ways to deal with coastal erosion
1. Zoning 2. Barriers 3. Beach renourishment
Divisions of pyroclasts
1. bombs 64mm 2. lapilli gravel sized 3. ash <2mm
Responses to stress from tectonic forces
1. brittle- when enough force is applied it will shatter (fast applied force) 2. ductile- when force is applied it will bend or warp (slower applied force) Response varies based on rock type, temp/press conditions, and speed of deformation
How do you decrease the C14/C12 ratio?
1. decrease atmospheric C14 - problem bc this does not happen, it is in steady state 2. Increase atmospheric C12
Types of metamorphic rocks
1. foliated 2. nonfoliated
4 Disadvantages of fossil fuels (nonrenewable) (general)
1. nonrenewable (once used its gone) 2. Deposits not uniformly distributed 3. Costs going up 4. Environmental damage
4 Disadvantages of nuclear power
1. nuclear electric price tripled between 1970-1990 2. Reactor safety- usually operates perfectly safe but when a problem happens, its a big problem 3. Nuclear proliferation- Are people using nuclear material for energy or weapons? (Iran) 4. Nuclear waste disposal- fission creates biproducts that can be radioactive
Textures of volcanic (extrusive) rocks
1. porphyritic 2.Aphanitic 3.glassy 4. vesicular
Length of metamorphism
1. prograde- portion of rocks history where temp/press is increasing 2. retrograde- portion of rocks history where temp/press is decreasing Changes within minerals can record temp/press changes
Requirements for radiometric dating
1. radioactive isotopes must be present in specimen 2. Need measurable amounts of both parent and daughter atoms in specimen. (No parent means clock stopped running and daughter means clock hasn't started yet) 3. Can only go so far back in time (run out of parents and a small amount is hard to measure. 5 half lives are the usual max) 4. Closed system- it is closed off from surroundings (no interaction with environment)
Decline of coal
1. regulations due to the toxic pollutants it releases make producing/using coal cost more 2. Natural gas is cheaper/cleaner/ more abundant 3. Traditional mines are replaced with mountain top removal that requires little manual labor and thus less jobs
Mineral properties
1.Color 2. Streak 3. Hardness 4. Luster 5. effervesences 6. crystal form 7. breakage patterns
Characteristics of explosive volcanic eruptions
1.Lahar-very fast moving mudslide that occurs before eruption starts 2. Pyroclasts- solid chunks of debris blasted into air 3. Pyroclastic flow- cloud of volcanic gas that moves at high speed and contains solid particles
SC vs NC
10 million gallons of water from Catawba river are used annually. NC was taking more water so SC sued. This case went to the Supreme court. This is an example of legal disputes over water.
Lithosphere
100km thick uppermost layer that is brittle
Wave changes as they approach the shore
4 things happen when waves get closer to the shore: 1. Wave speed decreases- when water is in shallow depths, it interacts with sediment to create friction. Magical number is when depth of water is 1/2 the wavelength. That is when the wave slows down. 2. Wave length gets shorter (scrunched)- when speed lessens, the waves get closer together 3. Wave height increases 4. Waves change direction (refracts)- They hit the coast closer to head on. Wave crest turns because one side of wave is slowing down while other is still moving fast (similar to meanders).
What does 4.5 GA mean?
4.5 billion years ago
Physical Layers of Earth
5 layers defined by their mechanical strength (is material brittle or ductile) and ARE NOT THE SAME AS LAYERS OF EARTH DEFINED BY CHEMICAL COMPOSITION: 1.Lithosphere 2.Asthenosphere 3.lower mantle/mesosphere 4. Outer core 5. Inner core
2018 indonesia earthquake
7.5 magnitude earthquake that happened in 2018 that has recently been classified as a supershear quake (siesmic waves move faster than normal)
Saprolite
A chemically weathered rock. Formed when rock goes through a lot of chemical weathering
Ventifact
A desert feature that is anything that has noticabely modified by the wind. Wind pushes tiny particles onto object and impact over time wears down object and makes it smoother.
Alluvial Fans
A desert feature where a lot of sediment has been deposited and is usually at end of Arroyo. Has distinct fan shape. Happens because water velocity drops at this point which can't hold sediment so the sediment just drops all at once
Arroyo
A focused area where water moves quickly and a lot of erosion occurs
Nebula
A large cloud of dust and gas in space
Trace metals
A proxy that looks at metal replacement in shells. Use ratio of Mg/Ca because metal replacement is dependent on water temperature.
Oil Shales and Tar Sands (OS and TS)
A source of oil. Shale/sands with high organic content are close but not fully formed oil. Can mine it and cook it to become oil. Advantages: 1. Very big deposits (OS resource has 4x more oil than Saudi Arabia) (TS estimated resource is 2x global)
Groin
A structure that is built 90 degrees relative to sea water. Protects areas with longshore current and stops longshore drift. Sediment gets stuck behind groin and can build up beach. Since changes effect system rapidly, erosion happens quickly in groin so more groins must be built. Very expensive.
Coal
A type of fossil fuel than is NOT a hydro carbon. It does have similar requirements for formation as hydrocarbons. Does not form on continental shelf but rather swamp areas. Formed from plant material. Advantages: 1. US coal reserve is big enough to last 100+ years at current rate
Artesian well
A well that is used with a confined aquifer on a hill. The water pressure on a hill (in right place) is high enough for the water to rise to surface. Cheaper than manual pumping water.
Coasts
About 55% of world population lives within 50 miles of coastline (3.85 billion). Coast is still on continental crust. Areas on coast change rapidly (by the hour) Different processes interact to form coastline. Wind blows on/off shore and waves move sediment around. Changes to system create ripple effect so other processes must recalibrate.
Superfund Act
Act passed by government in 1980 that helped areas that were contaminated with hazardous material.
2 advantages of wind power
Advantages: 1. Cost down 80% in last 20 years 2. Energy payback is only 1 year
4 advantages of algae biofuel
Advantages: 1. Doesn't need fresh water (any water works) 2. doesn't need crop land/ soil 3. Waste is biodegradable 4. Multiple harvests per year (yield is 15-300 times more than other biofuel crops like corn)
2 advantages of hydroelectric power
Advantages: 1. Doesn't pollute water at all 2. quick profit (Takes 5 years to recover plant construction costs)
3 Advantages of Methane
Advantages: 1. Resource has grown in recent years 2. Burns cleaner than other fossil fuels ( 30 % less CO2 than oil) 3. Price often cheaper than oil
4 Advantages of renewable energy (general)
Advantages: 1. abundant- lots of acsess to them 2. produce little pollution 3. Low maintinece- once built doesn't need much fixing 4. safe
Hot spot
An area with large volume of magma but is beneath lithosphere/plate. Hawaii is an example where the plate kept moving and volcanoes kept forming
Coda wave
An unusual and rare siesmic wave that is being used to monitor how carbon is moving underground
Expose to radiation
Annual expose to radiation from natural sources is counted in millirems (mrems). Sources: 1. Cosmic rays- 30 mrems 2. Terrestrial- 55 mrems 3. Fallout- 4 mrems 4. Medical- 100 mrems 5. Total- 284 mrems a year which is .3 of a rem
ANWR
Arctic natural wildlife reserve. Area set aside as a federal reserve to preserve the environment. Scientists estimated 20-30 billion barallels in resource in area (4-12 billion reserve). Pro drilling side: 1. 30 billion barallels is enough to last US 60 years. Frees US from foreign oil. Lower gas prices and tiny area is affected. The 30 billion number is the highest number from the resource range. They are assuming a 500 million/year rate of usage No-drilling side: 1. Only 12 billion barallels of oil is available which isn't enough to last the US for 2 years. Spills are expensive to clean and devastate the environment. 12 billion number is from reserve measurement getting used. They assume a 6 billion/year usage rate. It won't free us from foreign oil it would only cut imports by 14%. It won't keep gas prices low either because OPEC drives gas prices. Lot so oil is exported like in 2008 when US exported 500 million barallels to get US out of recession
Love Canal contamination
Area in Niagra falls NY where canals were being built in early 1900s but they were not completed. In 1940s chemical waste was dumped into these canals. In 1970s lots of rain caused a recharge in aquifer and brought the chemicals close to the surface. It was declared a state of emergency in 1978 and this led to the superfund act being passed.
Levee
Area next to channel that is slightly built up in elevation. They are naturally built up from sediment. Floods are a cause of these over time.
Tidal flats
Area of land that is underwater at high tide and exposed (as sand) during low tide
Solar farms
Area where you use mirrors to reflect sunlight to a central tower reciever that soaks up a lot of heat energy.
Plucking
As ice moves over a hill, the downward side of the hill gets broken off and those rocks are carried away with the ice. Moves bigger particles
Pressure gradient
As you go deeper pressure increases. Average is 300 bar/km depth. Surface pressure is 1 bar.
Magnetic anomalies of mid ocean ridge
As you go farther from ridge, magnetic crystals would point south instead of North and then reversed back. Prooves that Earth went through magnetic reversal where north and south would switch places
Slab pull model
At far end of plate, the plate is pulled down into a trench below the surface
Continental rise
At the end of the continental slope, it is an area where sediment is deposited. It is the end of continental crust
Nuclear waste
Average plant creates 25-30 tons of waste per year. 2017 the US has 71000 tons of stored radioactive waste. Since some waste has higher levels of radiation than others (takes longer to break down) it needs to be separated. Types of waste: 1. Low level 2. high level
Biological contamination of water
Bacteria microbes can be in drinking water and thus contaminate it
Classifying folds
Based on 3 things: 1. shape (antiform, synform, overturned) 2. age of layers relative to each other (anticline, syncline) 3. geometry (horizontal, plunging)- must look at 3d view (arial or second road cut)
Controlling nuclear reactions
Besides control rods, cooling systems remove heat energy through water. This water creates steam and drives a generator. Requires a lot of water (4 million gal a year in some plants). Cooling towers hold the hot water for it to cool before it is put back into the environment.
Cirque
Big area carved out with very steep walls. Bowl shaped. Has one open side GLACIAL EROSION FEATURE
Sea wall
Big concrete wall built parallel to coast where waves hit. Effective in stopping erosion but expensive ($1000 a foot). Areas with these see tourism rate drop because they look ugly
Pavements
Big rock chunks on surface of desert that can't be moved by wind. Only 20% of desert is covered in sand. Other 80% is covered in pavements (wind erosion in desert)
Distributaries
Branches of main channel that occur because of deposited sediment into large body
Lower mantle (mesosphere)
Brittle in nature which is caused by pressure, material, and temperature factors
Zoning (Coastal erosion)
Build farther inland. Look at setback distance and E lines.
Control rods
Built of material that soaks up neutrons and slows down nuclear reaction
Photosynthesis in C3 and C4 plants
C3: cooler, wetter climate ex: forest C4: hotter, drier climate ex: savannah/grasslands - Animals eat these plants so looking at fossils and seeing ratio signature of C3/C4 plant would show the climate is that of the plant
Nonrenewable energy
Can replinish themselves over a LONG timescale (geologic time scale)
Earthquakes
Caused by motion along faults. 1. Faults are held together by friction 2.stress builds up (elastic deformation occurs) 3. the stress is greater than friction and the plate slips and all the energy built up is released as siesmic waves.
Chemical contamination of water
Chemicals can get into water through infiltration and run off. Rain carries pesticides fertilizers, and pharmeceuticals into rivers
Chemical sediments
Classification of sedimentary rocks formed by chemical reactions like dissolution and re-precipitation and saltwater evaporation. Usually composed of one major mineral type (ex: Halite=rock salt, Quartz=chert).Sorting and rounding are not used with these. Economically important. Deals with dissolved ions
Detrial (clastic) sediment
Classification of sedimentary rocks formed through physical weathering. Classified by how big the rock is. Grain size is key
Biogenic sediments
Classification of sedimentary rocks that originated from plants or animals. (Ex: coal is composed of lithified plants)
Type of Glacial Sediment Deposits
Classified by grain size and sorting - erratics - tills - outwash - loess
CO2 buildup
Co2 buildup is higher today than past 400K years but graphs don't show where this excess CO2 came from.
Why are deserts found in polar regions?
Cold air does not hold water and polar regions are all cold air
Streak
Color of mineral when gounded in apowder
3 Disadvantages of solar energy
Disadvantages: 1. Variations in insolation- sun doesn't always shine (however extra energy is stored in backup batteries) 2. Some pollution occurs from older PV cells (Cadnium) 3. Where to put solar farms?- most areas in US that would be good solar farms are protected (conservation areas)
Hydrocarbons
Consist of methane and oil. Made of carbon and Hydrogen atoms and they are combustable. For hydrocarbons to form must be in area of high biological productivity and must have relatively low oxygen in waters/sediments to stop decay. Continental shelf is idea
building codes for earthquakes
Construction codes that help in areas of high earthquake activity. Prevent building on fault lines. Rock is best material to be on top of during earthquake because it has a low vibration
Chemostratigraphy
Correlation based on chemical markers
popigai center
Crater in northern Russia formed by a 5-8km asteroid and it produces diamonds with unique properties such as helping to create polished surfaces
Dendrochronology
Dark rings of a tree represents end of year for tree when it is hibernating. Can extend record back 14000 years. Need to look at specimen closely because not every tree grows rings and some form more than 1 ring per year
Sub groups of silicate group minerals
Depend on how tetrahedra polymerize. 1. Island silicates 2. Chain silicates 3. Sheet silicates 4.f framework silicates
Kettle Lakes
Depression in between kame that melt water got stuck in ex: Minnesota ("Land of 1000 lakes") GLACIAL DEPOSITIONAL FEATURE
Playa Lakes (Playas)
Desert feature that are Isolated lakes with no river or stream flowing in or out. Formed by depression in surface that rain collects in (big puddle). They evaporate due to lack of rain. As Playa is evaporated chemical sediment is formed like halite.
Dunes
Desert feature that is A wind deposit of sand that MUST BE IN MOTION. Needs wind to blow sand a bump where the sand builds up behind bump.
Inselberg
Desert feature that is a big dome of rock above ground level with most of the rock still below ground level. It is an igneous pluton that is now above ground. They are harder to erode than sedimentary rocks in a desert environment
Risk assessment map (landslides)
Determines how safe an area is from a landslide. Must be updated frequently
Volcano types
Different types based on type of eruption and erupted materials: 1. shield volcano 2. Tephra (cinder) cone 3. Stratocones (composite)
High Level (HL) Waste
Direct biproducts of fission. Isotopes that are radioactive. Main types are from power plants and weapons research. Needs heavy shielding and deep burial. We generate 12000 tons a year.
2 Disadvantages of Methane
Disadvantages 1. It is a sour gas 2. Still contributes to atmospheric CO2 buildup
2 Disadvantages of fracking
Disadvantages: 1. Contamination. Fracking fluid can get into water supply. Some of this fluid is composed of diesel fuel so this leads to fights over regulating industry. 2. Fracking leads to siesmic activity (Oklahoma has a lot of siesmic activity due to fracking) Scientifically fracking is safe if done correctly
2 Disadvantages of coal
Disadvantages: 1. Creates more pollution than other fossil fuels (25% more CO2 than oil) (mercury and arsenic produced in mining) (clouds of ash) 2. Acid rain formation- when coal is burned it has pyrite in it and when combusited it releases sulfur which creates acid rain. Acid rain makes weathering damage and the Ph change in water causes fish to die. Also drives nutrients out of soil
3 disadvantages of wind power
Disadvantages: 1. Not consistent in many areas- Areas defined by classes 1-7. Only class 3 and above is viable for this energy. 2. Best sites often far from poulation centers making transportation expensive 3. People don't want it near them (Not in my back yard effect) because they look ugly
3 disadvantages of hydroelectric power
Disadvantages: 1. River must be banked so resevoir creation floods areas behind dam. 2. Dams alter down stream environments- sediment is stuck behind dam so water just erodes because it isn't holding any sediment 3. Site selection- all good sites are taken so it is hard to find a good site
4 Disadvantages of renewable energy (general)
Disadvantages: 1. Technology is still being developed which slows down advancement 2. Expensive- research costs a lot which means energy costs a lot 3. Infrastructure compatibilty (Ex: cars that run on electricty) 4. Acceptance by society- People need to accept it (Ex: dollar coin)
2 disadvantages of algae biofuel
Disadvantages: 1. currently expensive 2. Doesn't lower atmospheric CO2 levels as some claim. (When algae dies the remains get burned which releases CO2 into atmosphere)
3 Disadvantages of Oil shales and Tar sands
Disadvantages: 1. produces more greenhouse gases (25-50% more CO2 than oil) 2. expensive to do so its not profitable at low oil prices 3. mining operations cause lots of environmental damage
Stratigraphy
Discipline in geology where you analyze strata (layers of rock) in detail. Age of layers relative to each other can determine age of fossils found in layer
Setback distance
Distance from coast that is considered safe
Asthenosphere
Ductile fashion that bends or oozes
density stratification
Earth becoming layered because the materials with different densities would separate (low density materials rised to top and high density materials sank to bottom) and each layer formed had a different density. Without these layers, Earth's magnetic field would be weaker
Theia Impact
Earth collides with another planet (Theia) that was about the size of Mars
Geothermal gradient
Earth's temperature change going down based on depth. Average is 30 deg C/km depth.
Phanerozoic
Eon divided into three eras: 1. Paleozoic- from 550Ma to 200Ma where the cambrian explosion occured ( huge diversity of life forms) and defines boundary between eons 2. Mesozoic- from 200Ma to 65Ma where dinosaurs were on Earth and ends with extincition of dinosaurs 3. Cenozoic- from 65Ma till now and is defined by the dominance of mamals
Proterozoic
Eon from 2.5Ga-550Ma where oxygen builds up in atmosphere an earth experiences its first ice age (has gone through 3)
Hadean
Eon from 4.5Ga-4Ga where theia impact occured and earth builds up atmosphere and oceans show up
Archean
Eon from 4Ga-2.5Ga where the oldest fossils show up(first life) and first continents show up
Nebular Hypothesis
Explains how solar system came to be 1. gravity pulls atoms together 2.Nebula collapses and gas rotates (solar disk model) 3.Protostar forms (early stages of star) 4. Fusion occurs when temperature is high enough and causes protostar to become a star and creates different elements
What are the 5 types of dunes?
Factored by the variance in wind direction, sand availability, and vegetation. 5 types: 1. Barchan Dunes 2. Transverse dunes 3. Linear (Longitudinal) dunes 4. Star Dune 5. Parabolic dune
Dip-slip faults
Fault type where motion is vertical and typically inclined. 3 types: 1. normal- hanging wall moves down and foot wall moves up 2. reverse- hanging wall moves up and foot wall moves down 3. thrust- hanging wall moves up and foot wall moves down but fault is very low angle and almost parallel to the ground
Cut Bank
Feature of a meander that is the outer part of a meander. Erosion eats at bank and it is where the water is moving fast
Point Bar
Feature of a meander where sediment is deposited across from cut bank. Water moves slow so the bank is built up (Think of marching band speed as an example). Both point bars and cut banks occur because water on the outer curve moves faster to catch up with the water on the inner curve.
Continental shelf
First part of continental margin as you go off shore. Big flat area. It is economically important because it has a lot of oil/natural gas. Also good for fishing because of nutrients on the shelf is good for fish. Farther from shore means less nutrients and less fish
Flood plain
Flat plain that water goes to when it floods. Lots of commercial development occurs here.
Synform
Fold where rock layers are warped downward (looks like a U)
Antiform
Fold where rock layers are warped upward (looks like upside down U)
Andesitic magma
Formed in mantle and is 60% SiO2. Ring of fire is where andesitic magma is commonly found. Subduction zones are where this magma is formed as magma goes through crust it changes to andesitic. It is a dry magma around 900-100 celcius
Recurrence interval
Found by dividing the number of years that you want to see an event happen by 1. It is a percentage of how likely the event will occur. PROBABILITY NOT A GUARANTEE. Varies from river to river
GA vs TN
GA proposed to move state border 1 mile north to get a river they desparety needed. Claim was based on 1818 surverying error saying that the border was placed in the wrong location.
Sour gas
Gas is mixed with other stuff you don't want. Methane is a sour gas that contains H2S.
V-shaped valley
Gentle sloped valley that a river forms from eroding it
Metamorphic facies
Group of index minerals that like same temp and press ranges. There are 7 major and on chart, they show conditions that the facies forms at. Use facies to reconstruct how metamorphism occured.
Mineral Groups
Grouped by a common anion 1. Sulfides-Sulfur anion 2. Oxides- Oxygen anion 3. Sulfates- Sulfate anion good for construction 4. Phosphates- Phosphate anion important for nutrients but not abundant 5. Carbonates- Carbonate anion found on surface of earth and pass effervesence test 6.Silicates
Carbon 14
Half life of this isotope is 5730 years which means it can measure in 10 half lives which is about 60000 years. It is produced in Earth's atmosphere and is steady state which means the amount you add equals the amount you subtract (no excess). Method of radiometric dating that is developed by first dating things you already know the age of. It can date fossils but not rocks because Carbon 14 in atmosphere is absorbed by plants and then eaten by animals. Carbon 14 tells us when the specimen died
Determining hanging and foot wall
Hanging wall is above the fault angle (\<- hanging) and foot wall is below fault angle (foot ->\)
porphyritic texture
Has some large crystals (phenocrysts) mixed with small crystals (ground mass)
How does the hydrosphere control climate?
Helps to transfer heat because water has a high heat capacity. - Gulf stream -thermohaline circulation
Yucca mountain
High level waste site that was supposed to be the first US site for spent nuclear fuel. Was supposed to open in 1985 but still hasn't opened. Many fault lines in area may cause problems. People in Nevada don't want nuclear material that close to them.
Saltation
Hopping, skipping motion of sediment due to wind. Saltation sediment builds up and eventually is exposed again which moves sediment yet again
Breakage patterns
How a mineral breaks. Two types: 1. Fracture- no fixed pattern when it breaks 2. Cleavage- very set pattern when broken.
Hardness
How durable mineral is tested by scratching it. Measured by Mohs scale.
Rem
How likely Radiaition will cause biological problems like tissue damage. Metric unit,
Accomodation space
How much dirt a basin can fill
Reserve
How much material is avaliable for for IMMEDIATE use
Recharge
How much water is added to aquifer mainly by rainfall.
Flood discharge
How much water is leaving/flowing past. Measured by velocity times cross sectional area. Both measurements vary from place to place so this is hard to measure.
Discharge
How much water is taken out of aquifer mainly by wells.
Fracking
Hydrolic fracture. Drilling oil well into impermeable layer. Fluid is pumped into well and the pressure shatters rock which creates permeability. Adavantages: 1. Gets oil out of areas where traditional drilling can't. Reason why production is up
Fracture porosity
If rock is fractured, water can fill up cracks which adds to ground water supply. In a lot of areas it isn't important but areas that do have it, fractures are very important to porosity.
Aquitard
Impermeable layer that prevents flow
Chernobyl
In 1986 a meltdown occured where radiation got into environment. Fallout was 30 times more than bombs dropped on Japan. 19 mile radius of plant where you are not allowed to enter in. Human error caused this
Hydroeletricity with tides and waves
In coastal areas, convert kinetic energy of waves into electricity. New buoy system is composed of a center of copper wire and a case of a float that is an electromagnet that generates flow of electrons. Concerns: 1. Rough environment- storms, wildlife, and rust can damage buoy 2. Could change coastal environments when it reduces wave energy 3. some areas are far from coasts for this to be useful 4. Effects on wildlife- some animals use electromagmets for sonar and these can disrupt those signals
Channels with steep elevation gradients
In mountain areas, channels are very straight. This is because the water flows downhill and has a high velocity. Since its moving so fast, it can cut through almost anything in its path.
Krakatoa
Indonesian island volcano that erupted in 1883 and was 1300x more powerful than the atomic bomb. Killed off entire cultures and it took 5 days for air pressure disturbance to subside
Tambora
Indonesian volcano with a supervolcanic eruption (had global impact) in 1815 that lowered temperatures
Porosity
Infiltration property that is how much open empty space there is to hold water (percentage). Determined by the sediment/rock properties. Well sorted sediment means more free space and higher porosity. More cementation (cement added) yields a lower porosity. 3 types: 1. Intergranular pores 2. Fractures 3. Vugs
Permeability
Infiltration property that is how well connected the pore spaces are. Well connected pores yields high permeability.
Three mile island
Island in PA where in 1979 a partial core melt down occured. No serious radiaition release was reported. Reason why there was a gap in nuclear exploration
What was our solar system like 6 billion years ago
It had not yet formed and was just a nebula of H atoms
Land Bridges affect rainfall bc...
Land bridges blocks currents and redirects the currents which affects heat flow. When the land bridge collapses it redirects currents like Antarcitca where cold currents circle the continent
Tectonic plate collisions at equator
Last three ice ages have been linked to tectonic plate collisions in the tropics. The collisions expose carbonate rock and the weathering of this rock disrupts the carbon cycle and less carbon ends up in the atmosphere. Since carbon is a greenhouse gas, less carbon means less heat is trapped and thus earth becomes colder.
Mantle
Layer of Earth under crust that is 45-2900km thick and is composed of denser elements like Magnesium, Manganese and Iron
Outer Core
Layer of Earth under mantle that is mostly composed of Iron and Nickel but contains a little bit of oxygen
Inner Core
Layer of Earth under outer core that is almost all Iron and Nickel
Ore
Layer with high concentration of something valuable
Contact metamorphism
Metamorphic change caused by increasing temperature. Occurs where magma pushes up to surface. Small scale process (only rocks close to magma change)(temperature caused)
Seafloor metamorphism
Metamorphic change caused by sea water. Happens near mid ocean ridge. Sea water fills crack and is heated up to change rocks
Regional metamorphism
Metamorphic change where pressure goes up causing change. Happens where plates collide. Happens on bigger scale (pressure caused)
Fault metamorphism
Metamorphic change where rocks at fault line change when fault line moves. Small scale change where it looks crushed up and layering is wavy/ distorted. (pressure caused)
Moment scale
Like richter scale except it measures how much rocks slip along a fault at the focus. You can still measure with scale even if you missed quake. At lower values, scale is close to richter but bigger values is when the scale starts to diverge.
Magma
Liquid rock below ground that is composed of gasses and SiO2 which classifies the type of magma. Three types: 1. Basaltic 2.Andesitic 3. Rhyolitic
Deflation
Little particles are moved by wind and ground level is slowly lowered. (wind erosion in desert)
Unconfined aquifer
Located above aquitard and is an aquifer where water goes back into layer since the layer above it is permeable.
Why a slope becomes destabilized (land slide may occur)
Location is important! Unstable slope doesn't mean landslide will automatically occur 1. lack of moisture- dry sediment makes particles not bond as well which makes them fall 2. Excessive moisture- too much water added to sediment makes mud which is not stable 3. Lack of vegetation- plant roots bind soil and water together so lack of it destabalizes slope 4. Excessive vegetation- too many plants takes moisture out of dirt and weight of many plants both cause destabilization
Microbes in water at beach
Look this up or find it out
Delta
Looks like a triangle on a map. It is located around the mouth of a river. It is a triangle shape because there are many distributaries here.
Branching/Dendritic Tributary
Looks like branches on a tree. Where tributaries join, it is a small angle less than 90 degrees. Very common and is what is expected in most areas
Ridge push process
Magma applies force to plate on mid ocean ridge and causes it to slowly move
Rhyolitic magma
Magma that forms in continental crust and is composed of 70%SiO2 (high). It is 700-800 celcius because more SiO2 lowers temp.
Where are deserts found?
Many are found around 30 degrees latitude due to Hadley cells that contain dry and high air pressure masses sinking down there. Others are found in areas of rain shadow effect (West China being blocked by Himilaya mtns) . Polar regions also have deserts because cold air does not hold water.
Renewable energy
Material gets replenished naturally on a SHORT time scale
Angle of repose
Max angle of steepness for location
Floods
Measured by how much water moves past a point in a given time. Occurs when discharge increases until channel can't hold anymore. When flooding occurs, water slows and sediment is deposited in the flood plain. This is good because the sediment is good for growing crops because its full in nutrients. This sediment deposit can be bad though because flood plains are usually commericial areas and this sediment is hard to clean.
Metasomatism
Metamorphic change caused by hot ground water. Water breaks down some minerals and deposits new material. Old material is replaced with new. Creates ore deposits (fluid caused)
Composition of Earth's crust
Mostly Oxygen and Silicon 46.6 Oxygen 27.7 Silicon 8.1 Aluminum 5 Iron 3.6 calcium 2.8 Sodium 2.6 Potassium 2.1 Magnesium 1.5 other
Drumlin
Mound of sediment deposited from glacier with one steep side and one gentle slope side. - gives direction of glacier *glacier moved away from steep sides* (opposite of mountanee) GLACIAL DEPOSITIONAL FEATURE
Mars Rover
Nasa is testing new mars rover in Chile because the Atacama desert has high UV levels and is extremely dry which makes it similar to mars. It is looking for microbial signs of life
Why Uranium 235 is needed
Neutron guns fire neutrons into Uranium atoms to induce fission. Uranium 235 produces a chain reaction when this happens and more neutrons are formed. Since firing neutrons takes time and energy, these 3 extra neutrons produced are very useful.
Batholith
No distinct shape but very large compared to other plutons
Fossils fuels (nonrenewable)
Nonrenewable energy that makes up 81% of energy consumption in the US and globally. Fossil fuels by usage: 1. oil 36% 2. Natural gas 29% and increasing 3. Coal 16% and decreasing Other energy by usage: 4. Nuclear 9% 5. Hydroelectric 6% 6. all others 4% and increasing
Fecal cloriform count
Number of fecal coliform bacteria in 100 mL of water. It is used as a proxy. Drinking water must have NO bacteria to be safe. Swimming/etc can have 200 but can't be drunk
Slab suction
Occurs at subduction zone and sucks material down with slab from asthenosphere
Methane Bubbles
Off the coast of Washington, bubbles of Methane are coming out of seafloor. Methane comes from biological organisms. There is a fault here for the bubbles to flow along. This provides insight to the subduction of the cascadia plate as bubbles only appear on the plate boundary. This could mean powerful earthquakes for the area
Rocks
One or more minerals combined and maybe other components like fossils or glass. 3 types based on formation linked via the rock cycle: 1. Igneous- formed when magma solidifies 2. sedimentary- formed when sediment builds up 3. metamorphic- formed when sedimentary rock changes under temp/pressure
Low level waste sites
Only 3 Low level waste sites in US 1. Clive, Utah- only accepts class A waste 2. Richland Washington- Accepts class A-C waste but only from 11 North West states. 3. Barnwell, South Carolina- Class A-C waste but only for 3 states as of 2008
Vugs
Openings in rock that form by dissolution. Can be important source of porosity only to places that have vugs.
Bowens reaction series
Order that minerals form in series
Cape Hatteras Lighthouse
Outerbanks of NC has strong long shore current which creates lots of erosion. In 1868 a light house was built 1500 ft inland. By 1998 it was 120 feet inland due to the erosion from this current. To save the light house it was moved 2900 feet inland and it cost $15 million and took 23 days.
Oxbow Lake
Over time when meanders stretch, the loops start to touch and this cuts out the loop in the middle. An oxbow lake is this cut out loop that has been cut out from the expanding meander. It is horseshoe shaped.
Seismometer (seismograph)
Records vibrations. Want at least 3 seismometers to know the directions the vibrations came from (up/down, east/west, north/south). Tells when each group of waves arrived at location with time and amplitude. The times can tell us distance to epicenter based triangulating the 3 stations.
Wind power
Renewable energy that harnesses wind for energy. Total Wind generates 5 times more power than total energy consumption. 2008 wind generates 1,5% of global energy supply3
Hydroelectric energy
Renewable energy where a plant is built on a river or stream and water is used to spin turbines and thus create electricity. Most used renewable resource in US (6%).
Waste Isolation Pilot Plant (WIPP)
Plant in Carlsbad New Mexico that is a high level waste site. Only US site for trans-uranic waste disposal. In 1999-2006 over 5000 shipments of waste were deposited. It is half a mile underground and carved into a 3000 ft thick salt deposit (good because salt has very low permeability). Containers must be ventilated to prevent explosion. Site is expected to be full by 2070. It will be montiored for safety until 2170. It is marked as off limits for drilling, excavation, and development until 12170. Granite pillars will be placed on top of site to warn people in the future of the radioactivity.
Where quakes occur
Plate boundaries are where earthquakes are very frequent. Plate boundaries have deep focal points for quakes. Subduction zones tend to have earthquakes that occur deeper below earth's surface and these deeper quakes cause the most damage and have highest magnitudes.
Abrasion
Pressure from glacier wears off particles and they get stuck inside the glacier
Deposition
Process in which sediment is laid down in new locations.
Algae Biofuel
Process of growing algae and when they die, you convert their lipids into biofuel.
Fission
Process of taking an atom and splitting it apart. Releases a lot of radiation and energy
Rock cycle
Process that happens to rocks that can skip around 1. Magma cools to form igneous rock 2. Weathering reduces rock to sediment 3. erosion moves sediment around 4. deposition deposits sediment 5. lithification turns sediment into sedimentary rock 6. Sedimentary rock is pushed down and the temp/press changes rock into metamorphic rock which is called metamorphism.
Convection
Process where plates moved based on densities and temperatures. Heating up meant density decreased and materials would circulate. Convection cells occured in Asthenosphere
Alfred Wegener
Proposed continental drift hypothesis that said continents were once connected but then separated. Mesosaur is associated with him because the fossils were found in SA and Africa which prooved they were connected at some point.
Stratocones (composite)
Really big and steep structure with explosive eruptions. Lots of viscous material stacks vertically to make volcano steep
Beach renourishment
Replace eroded sediment with new sediment. Can create wildlife issues because they have a hard time interacting with dense sand. In miami beach the entire each eroded away in the 1950s. They spent millions in renousrishment and it worked. New Jersey tried it and the whole beach eroded away in 5 years. This just shows that you have to study areas before you try things like this out.
Clean coal
Requires using more anthractice coal (rarest) or to capture pollutants before they escape the power plant. Both options cost a lot of money
Moraine
Ridge of sediment formed as glacier melts. Can form many from one glacier. Built out of till deposits (poorly sorted) GLACIAL DEPOSITIONAL FEATURE
Rivers/streams
Rivers and streams can be used interchangeably but it is an area where a lot of weathering and erosion occurs. Rivers and streams are easy to access for water use. Flooding in rivers puts people in area at risk and that is why flooding is the most common natural disaster that kills the most people.
Confined aquifer
Sandwhiched between two aquitard (impermeable) layers. Water doesn't go back into aquifer since both layers around it are impermeable. Artesian wells are used with confined aquifers.
Mercalli Index
Scale of 1-12 in roman numerals that asses earthquakes based on property damage. Quakes can be ranked differently based on where they hit even if same power
Shoreline features
Shorelines differ in apperance. They depend on tectonics (near plate boundary?) and rock type (resistant to erosion?) and sea level fluctuations (tidal height) and storm size/strength
High tide
Sides facing towards and away from the moon (of Earth)
low tide
Sides of Earth in between facing towards and away from the moon
Oak Ridge, TN
Site of development for nuclear bomb. Many events of nuclear leakage has occured here.
Creep
Slow mass wasting where sediment slowly moves downhill
L (long) (surface) waves
Slowest siesmic wave that causes a 3-D rolling pattern. They stick closer to surface and cause more damage on surface. Moves side to side and up and down
Tributaries
Small streams that flow into the main river. Different types: 1. Branching/dendritic 2. Radial 3. Rectangular
Channel
Small valley carved out by erosion which is the path that water flows along.
foreshocks
Smaller motions that occur before main quake during stage of elastic deformation
Oil Window
Specific conditions for oil to form. About 2-5 km below shelf in depth. 150 degrees celcius is max. Too deep is gas and too shallow is Kerogen
Layers (Strata, beds)
Stacks of sediment
Silicate group minerals
Structure is very important and looks like a pyramid (tetrahedron). Most common mineral on Earth. Tetrahedron bond together (polymerization) and must connect at tips.
Biogeography
Studying distribution of plants and animals. Some animals are only found in certain climate conditions so if their fossils are found that indicates that the conditions of the area were that of the animals preffered climate.
Structural geology
Subfield of geology that studies how rocks get deformed (patterns). Not studying topographic features like weathering
Water supply
Supply of water is based on recharge and discharge. If recharge is greater than discharge then water table rises. Can be problem for construction where ground will be softer due to water. Contaminents will be let in. Overdrafting also affects supply of water
Photovoltaics (PV)
Taking sunlight and turning it into electricity (direct). Sunlight strikes a device made of semiconductors and when struck, these semi conductors knock an electron out of their outer shell which is used to power stuff
How rocks get deformed
Tectonic forces from plate to rock causes deformation. Different types: 1. Tensional- when rock is stretched or pulled apart (happens at divergent boundary) 2. Compressional- material is being squeezed from two different directions (happens at convergent boundary) 3. Shearing- material moves past each other side to side (sliding) and occurs at transform boundary
Rounding
Tells how rounded the particles of clastic sedimentary rock are. Tells about erosion distance and transport
Metamorphic grade
Tells what general pressure and temperature changes are for formation of metamorphic rock. 1. Diagenesis- rock is sedimentary beow 200 deg C and 300 MPa 2. Low grade- low temp and relatively low press 3. Intermediate grade- medium temp and medium press 4. High grade- high temp and high press Past high grade, rock is magma and no longer a rock
Risk assessment map (earthquakes)
Tells where earthquakes occur the most and are most powerful. Even if far from plate boundary, a divergent plate boundary can create a scar in an area that causes earthquakes
Principle of Faunal Succession
Tells which areas have the oldest rocks by comparing fossils and rock patterns
effervescence
Test to see if chemical reaction occurs with a mineral with the equation: HCl+CaCO3=CO2 + Ca+OH+Cl. Characterized by formation of bubbles and calcite is a good example of a mineral that effervesces.
Channels with low elevation gradients
The channels starts to meander
2015 Nepal Earthquake
The earthquake is being reviewed because scientists don't believe the one that occured in 2015 is the big one they were expecting. A bigger one is on the way
Yellow cake
The first step in extracting uranium ore. It is uranium that is not yet ready for use.
What are properties of plates?
The lithosphere is divided into plates that move over the surface of Earth. Crust is on top of a plate and Antarctica is a good example of the effect plates can have on the environment because it used to be full of life but then the plate shifted down and this changed the ocean currents and the climate system of Antarctica
Lithification
The process that converts sediments into solid rock by compaction or cementation.
Continental slope
The steep area at the end of the continental shelf
Braided stream/river
There are a bunch of channels looped together intertwined. There is not a main channel. Causes: 1. Variable discharge- happens in areas with monsoons. Fast water change 2. Large sediment supply causes sediment to be deposited in middle of channel and this causes the channel to split 3. Easily erodable banks- when bank erodes and gives way, the channel gets wider which forms more of these smaller channels
What are the layers of the Earth?
They are defined by their chemical composition and consist of: 1.Crust 2.Mantle 3.Outer core 4.Inner core
Waves
They hit shoreline all day. Wavelength is the distance between two adjacent waves (how far apart).
Barriers (Coastal Erosion)
They protect shores in one of two ways. Either by weakening waves to stop erosion or keeping sand from moving away (No longshore drift). Types of barriers: 1. Sea wall 2. Groin
Varves
Thin layers of sediment with alternating colors that form in water and when water freezes it changes color. One dark layer and one light layer represents one year. Tells the age and climate history of the area. Only good for local study and is easy to get destroyed
Energy payback (EPB)
Time measurement of how long it will take for energy produced to offset cost of building it. Since 2000 solar energy EPB has decreased 2-3 years.
Crust
Uppermost layer of Earth that is about 8-45km thick. Composed of light elements like Aluminum, Silicon, and oxygen. Two Types: 1. Continental- makes up continents 2.Oceanic- denser than continental and makes up ocean floor
Resource
Total amount of material known to exist (bigger than reserve) (Immediate and non immediate use)
Sequestration
Trapping of carbon in the lithosphere so it doesn't get into atmosphere.
Radial Tributary
Tributaries look they are radiating from one another. This feature tells us that there is a mountain or hill. The top of the mountain/hill is where there aren't any tributaries and the tributaries are coming out from it
Rectangular Tributary
Tributaries that meet at close to right angles so they look like rectangles. These tell us that below the surface of this tributary, there are a lot of fractures in the rock. This is because water follows the path of least resistance and so it it flows along these cracks. This area has a lot of fracture porosity which is good for a well.
Stages of coal formation
Trying to squeeze out everything that is not carbon Stages in order: 1. Peat- 50% Carbon that looks like leaves 2. Lignite- 70% carbon that is brown 3. Bituminous coal- 70-90% Carbon that is when coal can start to be used 4. Anthractice coal- 90%+ carbon that is ideal for being used (shiny in appearance)
transmutation
Turns waste into a useful application. Big in 1970s until banned in the US. Currently being revisited especially in Europe. Examples of transmutation: 1. Smoke detectors use 241 Am which is a radioactive biproduct 2. 137 Cs is a biproduct of nuclear testing which is being used to kill harmful microbes on crops
Tides
Twice a day water level increases and in between it decreases. hawaii has a tidal range of 1-2 feet. Bay of Fundy has a tidal range of 40 feet.
Methane
Type of hydrocarbon that is natural gas.
Oil
Type of hydrocarbon. 66% of oil is in middle east. 22% is in Saudi Arabia alone. 2.5% is in US. Middle East used to be on continental shelf and that is why they have so much oil
Foliated metamorphic rock
Type of metamorphic rock in a Sheet or layered structure. Exposed to differential pressure. Look at crystal size to determine metamorphic grade (more/bigger crystals means higher metamorphic grade). (Gneiss is alternating in color and schists vary in appearance because of different minerals present)
Non foliated metamorphic rock
Type of metamorphic rock with no layers. They are exposed to confining pressure . They are identified by the key mineral present (ex: Hornfel contains hornblende, amphibole. Quartzite contains quartz. Marble contains calcite)
Frost wedging
Type of physical weathering where water fills into crack and freezes which expands and wedges open crack
Ground water movement
Typically moves very slow because the water has to move through pores. Slow movement is good because aquifer won't drain very fast. Slow movement is bad because if a contamanent gets into the water, it will take a long time to flush itself out. Groundwater still erodes however even at slow speeds. This is because ground water carries dissolved substaces like CO2 and SO2 that dissolve carbonate rocks. This can cause surface material to cave in and collapse.
US oil production and Consuption
US used 7.2 billion barallels of oil in 2016 (20 million a day) which is more than we produce. In 2007 we had to import 75% of oil supply. In recent years, the amount US uses is decreasing and production is increasing
Mid ocean ridge
Underwater chain of mountains that wrap around the planet.
Laacher See volcano
Underwater volcano in Germany that scientists are studying because of earthquake activity underneath that is caused by movement of magma
Uranium and nuclear power
Uranium 235 is what produces power. Uranium isotopes need to be separated to separate 235 from 238 which is also called enrichment. Centrifuges are used to separate these two isotopes and can separate things with 3 Atomic mass units between them. Want fuel enrinched with 235 compared to 238. Power plants need 3-5% enrichment while weapons need 90% enrichment.
Biofuels
Use of biological materials as fuel. RENEWABLE IF MANAGED PROPERLY.
Radiometric dating
Use of radioactive materials for dating species
Color index
Used to ID composition of plutonic rock. Primary color of rock tells composition. 1. Felsic- light colored 2. intermediate- grey color 3. mafic- black/dark colored 4. Ultramafic- green/yellow
Biostratigraphy
Using fossils for stratigraphy
Lithostratigraphy
Using rocks for stratigraphy based on rock types to identify strata. Need to be careful to match rock types
Tide Height
Varies from place to place based on how well connected ocean is to coast. If the coast is well connected there is low tidal range. If coast is not well connected (Bayou) there is high tidal range
Viscosity of magma
Viscosity is how thick the magma is. It is controlled by the temperature (high temp low viscosity) and silica content (high content high viscosity). Viscosity controls the gas content of magma because a high viscosity traps gas which builds up pressure and results in an explosive blast.
Galapagos islands
Volcanic activity of the area suspected to be caused by hot spot 1100 km down
Low level waste
Waste with relatively low levels of radiation. Not originally radioactive but came in contact with radioactive material. Divided by classes A, B,C, and GTCC (greater than class C). GTCC is called intermediate in Europe.
Perched aquifer
Water collects above impermeable layer (aquitard) on hill while main aquifer is still below impermeable layer. These aquifers are closer to the surface and can be used easily for water except not high supply.
Colorado river overuse
Water from this river provides to 30 million people. 70% of water is used to irrigate 35 million acres of crops. In 10 years of drought the water level went down 130 ft since 2000 in some areas. Flow rate estimated to drop 5-20% in the next 40 years. River ends 50 miles before reaching the Pacific Ocean.
Unsaturated zone (aeration) (vadose)
Water has not completely filled pores and air is present. Is located closer to surface above saturated zone.
Desert Erosion
Water is still important but is very sparatic. Rainfall is rare but when it happens it produces a lot. Lots of dirt and sediment is transported since there is little vegetation to keep it in place. Arroyos are formed from rain
Cone of depression
Water table is being compressed down which creates a cone where the well is. This affects other wells nearby because as water table lowers, wells with shorter pipes will run dry.
Potable water
Water that is safe to drink and is considered tasty by most people. Must be BOTH to be considered potable. Potable water doesn't mean its free of material. Material can be safe just ask whats in the water and how much
Water Quality
We need about 50L of water a day per person to live comfortably. Water must be potable to drink
Wave refraction
Waves bend when they get closer to coast
Photovoltaic cells
What is made of the semi conductor and is struck by sunlight. Over 100 years old but early cells were not effiecient (1%). Constantly improving (46-48% now).
Meandering
When channel moves side to side and bends. This is because the elevation grade is low and water moves slowly. This in turn, means that water has to move around any barriers. Meanders move over time which causes some territory to lessen (ex: Rio Grande). Mississippi should have moved due to meandering but hasn't because of artificial levees. Features of meanders: 1. Cut Bank 2. Point bar 3. Ox bow lakes Farther down a meander, the positions of cut banks and point bars change. Over time, meanders are stretched.
Radioactive
When isotope is unstable
Collision Zone Uplift affects climate bc...
When plates collide it creates moutains and thus a rain shadow on the other side of the mountains
Overdrafting
When recharge is less than discharge and water dwindles (water table lowers). Effects of overdrafting: 1. Cone of depression 2. Subsidence 3. In coastal areas, salt water fills in area where water was pumped out
Unconformities
When there is a gap in time present in the strata. Can be caused by running out of sediment, running out of accomodation space, or material getting eroded away (can happen even when depositing sediment). 3 types: 1. disconformity 2. nonconformity 3. angular unconformity
Runoff
When water flows off ground surface into ocean, streams, etc
subsidence
When water is taken out, layers close to the surface can pack down in the space water used to be. Ground level is lowered and this is hard/impossible to fix
Infiltration
When water soaks into ground. Forms ground water supply
Saturated zone
Where pore space is filled with water (Phreatic zone) closer to bottom.
Weathering
Where rock is broken down. 2 types: 1. Physical- rock is physically busted apart (can be caused by plant roots) 2. Chemical- Most common in many environments. Caused by chemical reactions (ex: Feldspar and water)
Basin
Where sediment is deposited (holes)
Divergent margins
Where two plates meet they pull away from each other. Two types: 1. Mid ocean ridge plates move away from ridge which is charecterized by volcanoes and earthquakes 2.Continent splits(rift valleys) that still have volcanic activity and earthquakes
Transform margin
Where two plates meet, they just slide past each other
Convergent margin
Where two plates meet, they run into each other. Two types: 1. Subduction zone- oceanic crust collides with continental crust and the oceanic crust is shoved down because the continental crust is less dense. Most powerful earthquakes occur here 2. Collision zone- when two contients collide, rock is pushed up and mountains are formed
Mouth of river
Where water empties out into large body of water. Close to mouth, erosion stops and lots of deposition occurs. This forms distributaries. A lot of subsidence occurs at the mouth of rivers. (Ex: Venice Italy)
WARP turbines
Wind Amplified Rotor Platform. Stacks of platforms with blades on each that harnesses wind power. Looks more pleasing than standard wind turbines.
Plunging fold
fold where hinge is clearly seen (from top view) and layers look tilted (from side view). Most likely to happen
Disconformity
a type of unconformity where sedimentary rock is above and below unconformity
Nonconformity
a type of unconformity where sedimentary rock lies above unconformity and other rock type is below it
sheet silicates
layers of silicates and cations stack. not bonded well. Produces 1 cleavage plane
Liquefaction
area built on soft sediment sinks into mud due to earthquake
S-wave shadow zone
area where no s waves occur because they stop at outer core
Drainage Basin
area where total water in area feeds into river/stream. This is because water flows downhill
Half-life
amount of time for half of parent atoms to break down (looking at group of parents ). It is a unit for dating and helps establish time. As parents decay daughters form so amount of each are inverse of each other up to 100%. Half lives do not vary with any environmental factor
Cementation
an adhesive (water) makes compact sediment stick together when water leaves behind material
Topographic feature
anything you can see on a landscape (hills rivers, etc)
Principle of cross cutting
applies to two features intersecting each other (fault lines). Whatever did cutting is youngest and whatever got cut through is oldest
fractional crystallization
as magma cools the rock formed is missing component from magma
Daughter atom
atom produced after decay. If still not stable after decay, it will keep producing daughter atoms until stable
Parent atom
atom you start with
Plutons
big body of plutonic rock cooled below ground.
Water table
boundary between saturated and unsaturated zones
framework silicates
builds in 3 dimensions. Include some of the most common minerals like quartz
Aphanitic texture
can't see any crystals and is dull looking
Correlation
comparing strata in two different areas to see how they correlate in time. Correlation determines short periods of time.
Primary (P) waves
compressional wave (material moved through is expanding and contracting) that can move through almost anything. Fastest type of siesmic wave. First to reach a location. Moves through core
Magnetostratigraphy
correlation based on magnetic patterns/signals
sequence stratigraphy
correlation where you use sequence of unconformities to determine age. You need a bunch of unconformities and this occurs a lot in coastal areas.
Longshore current
current running parallel to coast. Follows winding pathway because it interacts with waves
Dike
cuts vertically through rock layer
Hydrologic cycle
cycle in which water in hydrosphere moves. (Look at diagram and focus on numbers).Oceans and glacial ice hold most water. After that, ground water holds a lot of water while surface water like lakes/streams don't hold as much as ground water.
Relative dating
dating method where you try to arrange events in a sequence. People got interested in this dating because of fossils.
Richter scale
developed in 1930s and measures how much ground motion occurs on a scale from 1-10. It is an index scale meaning each magnitude is significantly larger than the other. Depends on distance from focus which is a problem. If you didn't record data at time of earth quake, you can't use scale which is another problem
island silicates
doesn't bond with other pyramids
Folds
ductile response due to compressional force. Can come in any size. Common for folds to be strung together
Continental margin
edge of continent close to off continet and oceanic crust. It can be classified as active or passive. Active is when there is a plate boundary at that location (West Coast). Passive is when there is no plate boundary (the transition form land to sea is still the same plate) (East Coast).
Greenhouse Effect
energy that is reflected is not all let out into space and is trapped by atmosphere. Wavlength of energy coming in can pass but is changed when it hits surface and now cannot pass
glassy texture
even smaller crystals and smooth texture
Chain silicates
faces are added at end or 2 chains added together
Types of mass wasting
fall, slide, flow, creep. Categories based on material, type of movement, speed
Strike-slip fault
fault where rocks move in a side to side motion ( horizontal from arial view). Two types: 1. left lateral: if you are on fault looking to other side, on both sides it looks like everything was shifted to the left 2. right lateral: if you are on fault looking to other side, on both sides it looks like everything was shifted to the right.
Overturned
fold where it looks like a synform or antiform just turned. Name it using overturned (synform or antiform) based on what it most resembles. If can't determine which it most looks like, call it overturned fold.
Horizontal fold
fold where layers compress to form fold. Looks horizontally stacked so you can't see the hinge (from top view)
Syncline
fold where oldest layer wraps around fold and youngest is in the center
Anticline
fold where the oldest layer of rock is in center between two limbs
Crystal form
form mineral naturally wants to form in
Crystallization
freezing magma into igneous rock
Joint
geologic structure that is a brittle response to a tectonic force (cracks). Occurs in all sizes and in groups. Most common type of geologic structure
Fault
geologic structure that is a brittle response to a tectonic force. The rock is cracked and movement occurs along and between cracks. Can be any size and likely to occur in groups. Classified by slip direction (what direction rocks are moving)
Glacial Erosion
glaciers can move particles of any size
Vesicular texture
has tiny openings in structure because gas escapes from late stage of magma cooling
Luster
how light bounces off a mineral
Pahoehoe
lava in a stage of cooling where there is a thin crust but is very mushy and hot and still moving around a lot
Aquifer
layer of material that can pump water to surface for use via wells. Wells are expensive so a well should be below water table to get more water. 3 types: 1. Unconfined 2. Confined 3. Perched
E-lines
lines along coast that marking where erosion will move the shore line to in the future. (Represented with E and the # of years). The formula is erosion rate times the interval of years. To be considered safe by federal government a building needs to be E-60 away which is based on the life expectancy of the building and a ten year cushion. States like SC use E-40 though because of their high reliance on tourism ($18 billion a year in revenue is made from beach tourism in SC).
Subsidence
lowering of ground level. Causes more accomodation space to basin which can make subsidence occur again
Equilibrium Crystallization
magma started out with forms rock with same chemical properties
Radiation
material ejected from unstable radioactive atom during decay (energy and particles)
Absolute dating
method of dating that tells exact dates. Two types: 1. Non-radiometric (varves and dendrochronology) 2. radiometric
Compaction
more layers added force sediment together
Longshore drift
movement of sediment caused by longshore current
aftershocks
movement that occurs after main quake. Happens because main quake doesn't release all energy and stress is introduced to new rocks farther away
Angular unconformity
not dependent on type of rock. Rocks are tilted at an angle below gap. Takes a lot of time because several steps are involved
Tephra (cinder) cone
not very big volcano because pyroclasts are mostly ejected and not magma which leads pyroclasts to stack up
Intergranular pores
openings in between the grains of sediment. In most locations, this is where most ground water is stored
Geologic time scale
originally built via stratigraphy. Fossils were key for defining boundaries. They were divided into eons which were divided into eras which were divided into epochs
Uniformitarianism
principle that says processes acting on Earth have been acting the same way all throughout Earth's history. Principle uses little changes that take a lot of time
Planetary Accretion
process of molecules colliding with each other that builds up planets over time. Process still occurs and this is how Earth was formed 4.5 billion years ago
Seafloor spreading
process where magma forms new rocks at mid ocean ridge that push the older rocks out. Showed that continents could drift
James Hutton
published theory of the Earth and this gave birth to geology
Partial freezing
range of temperatures eventually makes magma form crystals
Solar energy
renewable resource. If capture all sunlight for 1 hour it would be a years supply of energy for the planet. If use 7.5% of Sahara desert as solar farm it would provide half of worlds energy needs.
Actualism (Uniformitarianism)
revised uniformitarianism that said speed of processes could change over time
Parent rock
rock you start with and is eventually changed
Sill
runs parallel through rock layer (horizontal)
Decay series
sequence of parent to daughter atom until atom becomes stable
Secondary (S) (shear)waves
shear motion occurs when passing through material. material is shifted up and down. Moves slower than P waves by around 50%. Does not move through liquid well. Stop at outer core and fizzle out
Shield volcano
shield shaped and gradually slopes down. Most common volcano type. Basaltic magma is primary erupting
Focus
spot on fault line where an earthquake occurs (most only 2-20km deep in crust)
epicenter
spot on surface above the focus.Most of the time epicenter is not on fault line. It is the area that is hardest hit by quake
Aa
stage where lava is more solid rock but not completely cooled. Vesicles are formed in this stage because gas is still escaping
Volcano Explosivity Index
tells how much material is ejected in a blast
Sorting
tells how uniform grain size of clastic sedimentary rock is. Erosion makes particles close to uniform (well sorted). Goes from poor to intermediate to well sorted and tells how far the rock has been transported
Metamorphism
the process in which one type of rock changes into metamorphic rock because of temperature, pressure, or fluid factors. Very slow process. Good at telling us history of conditions present in formation of rock. Metamorphic rock contain more rare and exotic minerals with unique properties. Most form around 10-30km depth (mid-lower crust)
Erosion
the transport of fragments of rock by water, wind, ice, or gravity.
Catastrophism
theory that states that natural disasters such as floods and volcanic eruptions shaped Earth's landforms and caused extinction of some species
Radioactive decay
unstable isotope ejects material to become stable
Index fossils
used to identify short periods of time. Criteria to be an index fossil: 1. Has to have a huge population 2. want to have widespread population (global distribution) 3. need to have gone extinct quickly 4. must be easy to identify
Inner core
very brittle
Outer core
very ductile/fluid-like behavior
Cross section (road cut) view of fold
view of fold with the layers showing. Has two parts: 1. limb- part of fold where the fold is straight 2. hinge- part of fold where fold is bent (curved)
Principle of Original Horizontality
when you first make layers of sediment, they are horizontal
Principle of Superposition
when you have stacked up layers of rock, the oldest is at the bottom and the youngest is at the top
Current US use of nuclear power
• ~100 plants, ~20% of US electricity • Use declining since 1996 • Half the active plants will close by 2020 • No new reactors ordered btwn 1978-~2010 o 48% of the ones ordered before '78 were never built