environmental science exam 1 study guide
What happens when two continental plates collide? Two oceanic plates? Continental + oceanic?
a. Continent-continent = mountain building b. Oceanic-oceanic = subduction and volcanic island arc c. Continental - oceanic = subduction and volcanic arc
What are the four pieces of evidence that Alfred Wegener used for continental drift?
a. Puzzle piece fit of the continents b. Matching plant and animal fossils across continents c. Matching rock assemblages across continents d. Glacial striations e. He was not take seriously because he could not provide a mechanism for how the continents moved
What is the general location of the highest-recorded earthquakes?
along the edge of oceanic and continental plates
Which foundation material is most stable during earthquake shaking?
bedrock
What types of stress are associated with each type of fault?
compressive stress produces reverse faults, tensional stressproduces normal faults, and shear stress produces transform faults
What is the importance of the outer core?
creates a magnetic field
What was Harry Hess' contribution to plate tectonics?
described how hot magma would rise from under the crust at the Great Global Rift. When the magma cooled, it would expand and push the tectonic plates apart.
faults with pictures
idk idk
Know how to read a seismogram, i.e. the P-S arrival times and amplitude.
idk yet tbh
What element makes up most of the Earth's core?
iron
The __?__ of the Earth does not transmit S waves.
liquid outer core
What are magnetic anomalies? What would likely occur if the magnetic field reversed today?
magnetic anomaly is a local variation in the Earth's magnetic field resulting from variations in the chemistry or magnetism of the rocks damage cells, cause cancer, and fry electronic circuits and electrical grids
In which region of the Earth does convection take place?
mantle
Which region in the Earth consists primarily of solid iron?
mantle
What is the relationship between earthquakes and plate boundaries? i.e. what types of faults occur at each boundary?
normal, reverse, strike-slip
Which crust is more dense, continental or oceanic?
oceanic
Which layer in the Earth does not transmit S-waves?
outer core
Which region in the Earth is molten?
outer core
What is the most abundant element in the Earth's crust?
oxygen
Which of the following types of seismic waves arrive at a seismometer first?
p
What two plates does the San Andreas Fault separate?
pacific and North American
What is the tectonic setting of the Hawaiian Islands?
pacific plate
What are reflected and refracted waves?
reflection: change in direction refraction: change in direction, speed
Know the difference between ductile and brittle deformation
rocks way of responding to stress break or bend
How do we know about the earth's interior?
seismic waves
What types of things occur during an earthquake?
seismic waves volcanic activity tectonic plates plate boundaries
Given that the epicenter was more than 200 miles away, why was there such massive damage during the 1985 Mexico City earthquake?
shock waves
Why are the Himalaya Mountains so high?
tectonic plate motions that collided India into Tibet
What can cause a tsunami?
1) Earthquakes 2) Volcanic Eruptions 3) Landslides 4) The impact of a meteorite or an asteroid
What is the minimum number of seismograph stations needed to locate the epicenter of an earthquake?
3
What is the approximate distance from the surface to the center of the Earth?
3,959 miles
How thick is the crust? Which crust is thicker, continental or oceanic?
3-5 miles for oceanic and 25 miles for continental
The energy released during a magnitude 8 earthquake is approximately __?__ times greater than the energy released during a magnitude 6 earthquake.
900
What is an anticline?
A fold in rock that bends upward into an arch oil and natural gas drilling
What is the Benioff zone?
An area of seismicity corresponding with the slab being thrust downwards in a subduction zone.
Given what you know about plate tectonics, is the seafloor likely to be older or younger than the continental crust?
Areas where new crust is being formed at mid-ocean ridges are much younger thanzones further away continental is older because it doesn't renew
What was Marie Tharp's contribution to plate tectonics?
Constructed the first map of the seafloor
What is the relationship between plate boundaries and earthquake depth?
Earthquakes take place along plate boundaries
What plant fossil was found on several continents in the southern hemisphere?
Glossopteris
What was Andrija Mohorovicic's major contribution to geology?
He was the first to say that the earth's interior had layers
Know who your LAB instructor is! NOT ME!
J bautista Lopez
What is the difference between Richter Magnitude, Moment Magnitude, and the Modified Mercalli Intensity scale (MMI)?
Mercalli scale describes the intensity of an earthquake based on its observed effects, the Richter scale describes the earthquake's magnitude by measuring the seismic waves that cause the earthquake. The moment magnitude scale is a measure of an earthquake's magnitude based on its seismic moment.
How does sedimentation contribute to the evidence for seafloor spreading?
More sediment accumulation near continents than mid-ocean suggests oceanic crust near continents older than mid-ocean
What is a dip-slip fault?
Normal and reverse
Why are there mountain ranges in the middle of oceans?
Oceanic crust is young ,warm, and condenses and thins as it moves from center
What does magnetic inclination tell us about where a rock formed?
Paleo latitude
What was Arthur Holmes' contribution to plate tectonics?
Proposed mantle convection
The __?__ magnitude scale is a measure of the energy released. It does not directly measure the extent of building damage.
Richter
What kind of fault is the San Andreas Fault? How large of an earthquake (magnitude) can the San Andreas produce?
Right lateral strike slip; 8.2
Who designed the first seismometer?
The Chinese
Why is there an area of "creep" along the San Andreas near Parkfield, Ca?
The San Andreas Fault has serpentinite at its base; serpentinite alters to clay allowing for easy slippage.
What is the S-wave shadow zone?
This the circular area of missing S waves that are unable to travel through the earth due to earth's liquid layer.
How well can scientists predict earthquakes?
We cannot yet predict earthquakes
Who discovered each of the layers of the Earth? a. Crust/mantle boundary b. Core/mantle boundary c. Inner core/outer core boundary
a. Andrija Mohorovičić b. Beno Gutenberg c. Inge Lehmann
What are the top four earthquakes ever recorded? Know the locations, dates, and magnitudes.
a. Chile 1960 9.5 b. Alaska 1964 9.2 c. Andaman Sea 2004 9.1 d. Japan 2011 9.0