Earthquakes & Earth's Interior
Continental Drift
Volcanoes
Vocabulary
Random
100
What is the difference between the epicenter and the focus?
The focus is the point where an earthquake starts underground. The epicenter is directly above the focus.
100
What was Wegener's hypothesis?
That the continents were once conjoined as a "supercontinent" (Pangaea) and have drifted apart over time through continental drift.
100
What are the 2 types of lava and briefly describe.
Pahoehoe- Smooth skin, not very viscous Aa- Rough & possibly sharp, usually more viscous
100
Continents were conjoined into this landmass about 300 to 200 million years ago, before they drifted apart.
Pangaea
100
How thick is the oceanic and continental crusts?
Oceanic= 0-7km; Continental= 8-75km
200
What are the 5 layers of Earth defined by physical properties? List from outer to inner.
Lithosphere, Asthenosphere, Lower mantle, Outer core, Inner core.
200
What are the three types of plate boundaries?
Divergent Boundaries, Convergent Boundaries, and Transform fault boundaries.
200
What are the 2 factors that affect volcanic eruptions and why?
Viscosity- The more viscous the substance, the more violent the eruption. Dissolved gases- The more gases involved, it increases pressure and the more violent the eruption.
200
What is viscosity?
Viscosity is a substances resistance to flow.
200
The dust from Mt. Pinatubo in the atmosphere lowered the average temperature of the Earth about...
One full degree
300
List the order of the arrival of seismic waves (fastest to slowest) and whether each is transverse and/or longitudinal.
P Waves- longitudinal; S Waves- transverse; Surface Waves- can be either longitudinal or transverse;
300
What is the difference between a trench and a ridge?
Trench- where two plates come together and form a raised ditch. Ridge- At a divergent boundary when oceanic-oceanic plates move apart and the magma flows over the rift and hardens
300
List the three types of volcanoes from least to most violent
Shield volcanoes, Cinder Cones, and Composite Cones
300
What is liquefaction?
Liquefaction is when seismic waves hit and can cause loosely saturated sediments to act like a liquid.
300
What type of volcano is Sunset Crater?
A Cinder Cone
400
What is the process you go through to locate the epicenter of an earthquake?
Triangulation- Using three seismographs to pinpoint a relative location for the epicenter.
400
What are the three mechanisms of plate motion?
Slab-Pull Mantle Convection Ridge Push
400
At what boundaries between which types of plates produce rift valleys and volcanic island arcs?
Rift valleys- divergent boundaries, continental-continental crust Volcanic island arc- convergent boundaries, oceanic-oceanic crust
400
What is the subduction zone?
The subduction zone is the zone from which the plate sub ducts underneath the other to where it melts
400
Why did the eruption from Mt. Pinatubo cause lahars?
There was a typhoon while the volcano was erupting. The water mixed with the volcanic ash to create lahars.
500
What are examples of short and long range predictors?
Short range predictors can be foreshocks, subsidence & uplift, and emissions of radon gas. Long range predictors are mostly historic records.
500
What are the four pieces of evidence for Continental Drift? Explain briefly.
The Continental Shapes- Some of the continents coastlines appear like they could fit together Matching Fossils- Scientists found similar fossils on continents that could potentially align Rock Types and Structure- Certain mountain belts end at one coastline only to reappear on a landmass across the ocean Ancient Climates- Evidence that landmasses had different climates at one time (ex. Glacial remains in equatorial regions)
500
List the four volcanic landforms. Briefly Explain.
Caldera- When a volcano collapses in on itself and creates a huge depression Necks & Pipes- Magma that has cooled in the pipe of the volcano and was left as the rest of the volcano weathered away Lava Plateaus- large amounts of lava that come out and create extremely flat, raised land Plutons- Magma from a magma chamber that has cooled and hardened
500
Explain the elastic rebound hypothesis.
States how earthquakes happen. (Earthquakes are produced when energy is released and the Earth rebounds back and forth)
500
What are the types of pyroclastic materials from volcanic eruptions from largest to smallest?
Blocks/Bombs, Lapilli/Cinder, Very fine ash or dust particles
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