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56 Cards in this Set
- Front
- Back
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lithosphere consists of 2 layers called |
crust (highest) and asthenosphere |
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Define continental crust |
forms the worlds landmass |
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Define oceanic crust |
lies below ocean |
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heaviest type of plate |
oceanic |
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lightest type of plate |
continental |
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the ___________ is the scientific theory used to explain how or why certain geographic phenomenas occur on earth |
theory of tectonic plates |
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process that causes plates and crust to move |
convection current |
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what makes the earths core hot |
radioactive decay |
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define convection current |
a continuous cycle of heating magma rising and pushing crusts (apart and together) the cooling and sinking |
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define diverge |
moving apart |
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define convergent |
moving together |
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define transform |
moving against each other |
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convergent plate movement form |
trenches , mountains, volcainos |
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divergent plate movement form |
ocean ridge, valley, |
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transform plate movement form |
fault lines |
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define earthquakes |
shaking or vibrating of the earths surface |
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normal faults are caused by ________ |
divergent plate movement |
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thrust / reverse fault are caused by _________ |
convergent plate movement |
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strike and slip fault are caused by __________ |
transform plate movement |
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define epicenter |
the point where the earthquake first reaches the surface |
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define focus point |
point underground where earthquake strikes |
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define seismic waves |
waves of energy ( vibrations) caused by a earthquake that travel though layers of the crust. |
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define foreshock |
a small earthquake before the main shock |
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define main shock |
the biggest earthquake in the series |
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define aftershock |
a small earthquake that occurs after the main shock |
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richter scales measure from __ to __ |
0-10 (no earthquake can be 10 fold) |
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where do geomorphic hazards mainly occur |
ring of fire |
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why don't geomorphic hazards have to occur on plate boundaries |
tectonic plates have small cracks inside them |
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whats the difference between hazards and disasters |
HAZARDS have the potential to cause damage DISASTERS have caused damage |
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5 factors that affect a hazards risk |
-duration -frequancy -proximity -vulnerablity -magnitude |
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Examples of adaptation |
New emergency response plans Building regulation Town planning |
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High risk is classified as what |
High frequency Close proximity High Vulnerability High Intensity |
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German scientist who came up with the theory of plate tectonics? |
Alfred Wegener's |
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The Africa and Arabian plate are an example of what boundary? |
Divergent |
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The Pacific Plate and Indo- Australian Plate are example of what boundary? |
Transform |
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Give an example of a convergent plate boundary? |
Nazca and South American Plate |
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Lower mantle is known as the |
mesosphere |
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Composition of Oceanic crust |
Basalt |
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Composition of Continental crust |
granite |
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Which crust is thicker |
Continental |
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define fault |
crack in the earths crust |
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most destructive and deadly earthquakes occur at what plate boundary |
Transform |
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Name three types of seismic waves |
PrimaryWaves SecondaryWaves SurfaceWaves |
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Primary waves |
thud feeling fastest wave first felt can travel through all layers |
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Secondary waves |
second wave felt only pass through solid layers creates rolling action |
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surface waves |
move along the crust/ surface slowest moving most destructive wave creates intense shaking |
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structure of the earth
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inner core outer core mantle - Lower mantle (mesosphere) - Upper mantle (asthenosphere) crust |
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label the tectonic plates |
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Convergent Plate Margin Continental and Oceanic |
- oceanic crust subduct - denser oceanic plate is bent and pulled under the continental plate - forced deeper into earth - high heat and pressure released - oceanic crust melts and forms magma, then magma chambers - creates volcanoes on the continental plate |
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Convergent Plate Margin Continental and Continental Plate |
- Plates are too light subduct - folds at the boundary and is crunched lifting up - formation of mountains and mountain ranges |
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Convergent Plate Margin Oceanic and Oceanic |
- older plate is pulled under younger one leads to formation of chains of volcanoes known as island arcs - can lead to mass earthquakes and tsunamis |
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Divergent Plate Margin Oceanic and Oceanic |
- cracks appears in the sea floor - magma fills the space - mid ocean ridge is formed - magma spreads outward new oceanic floor and oceanic crust |
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Divergent Plate Margin Continental and Continental |
- valley like rift forms - streams and rivers flow into the valleys and lakes can be created - widening crust may be thin enough that continent breaks off forming new plate |
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Transform Plate Margin |
- produces earthquake - jagged edges catch against each other - while locked together the pressure build at fault line - when plates slip into new positions the stress is released with sudden burst |
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Oceanic Crust |
lies below the ocean 5- 16km thich composition bassalt heavier - more dense Younger -re generated at divergent boundaries |
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Continental Crust |
Forms world landmasses 25 - 70km thich composition granited lighter - less dense Older |
