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Vocabulary

 * earthquake**- the shaking that comes from the movement of rock beneath the Earth's surface


 * stress**- a force that acts on rock to change its shape or volume


 * shearing**- force of stress that pushes a mass of rock into opposite directions.


 * tension**- the force of stress that stretches rock until it becomes thinner in the middle


 * compression**- a stress force that squeezes rock so that it breaks or folds


 * deformation**- any change in shape or volume in the Earth's crust


 * fault**- a break in the Earth's crust where slabs of Earth


 * strike- slip fault**- a fault that has rocks that moves past each other sideways with some up or down motion


 * normal fault**- a fault that is at an angle, so that one block of rock is at the top and the other is on the bottom of the fault


 * hanging wall**- half of the fault that lies above


 * footwall**- half of the fault that lies below


 * reverse fault**- the same arrangement as a normal fault but the blocks move in opposite directions


 * fault block mountain**- when a normal block lifts a block of rock


 * fold**- bends in a rock that folds when compression shortens and thickens part of Earths crust


 * antcline**- a fold in a rock that bends upward into an dome


 * syncline**- a fold in a rock that bends downward in the middle to form a bowl


 * plateau**- a large area of flat land, elevated high above sea level

Outline
T= Earth's crust in motion

1. Stress in the crust

1. Kinds of faults 1. Friction along faults 1. Mountain building
 * types of stress
 * shearing
 * cause rock to break and slip apart
 * tension
 * pulls on crust, stretching rock so it becomes thinner in the middle
 * Compression
 * squeezes rock until it folds or breaks
 * pulls on crust, stretching rock so it becomes thinner in the middle
 * Compression
 * squeezes rock until it folds or breaks
 * fault
 * strike- slip fault
 * rocks slip past each other sideways with an up or down motion
 * normal fault
 * fault is at an angle, one block lies on top and the other lies below the fault
 * reverse fault
 * same structure as the normal fault, but blocks move opposite directions
 * friction is force that opposes the motion of one surface as it moves across another surface
 * how rocks move along faults depends on its friction
 * friction low- rocks slide past each other without much sticking
 * friction moderate- sides of faults jam together
 * friction high- rocks lock together, don't move
 * friction high- rocks lock together, don't move
 * normal fault lifts rock, fault- block mountains for
 * m
 * when two plates move opposite, tension forms
 * tension makes normal faults
 * normal faults= parallel, rock lying between them goes upward
 * when rock slides down, valley forms
 * fault- block mountain ranges
 * Sierra Nevada of California
 * Great Basin
 * Great Basin

1. Mountains formed by folding 1. Anticlines and synclines 1. Plateaus
 * plate movement causes rock to fold
 * folds= bends in rock
 * folds= form when compression shortens, thickens crust
 * collisions in plates= cause compression, folding
 * made from compression in the crust
 * anticline
 * upward folds in rock
 * syncline
 * downward folds in rock
 * anticline examples
 * Black Hills
 * in South Dakota
 * Made 65 million years ago
 * syncline examples
 * Illinois Basin
 * stretches from Indiana to Illinois
 * filled with soil and rock
 * stretches from Indiana to Illinois
 * filled with soil and rock
 * filled with soil and rock
 * large area of flat land above sea level
 * form when vertical faults push up large rock block
 * has many flat layers
 * is wider than is tall
 * examples of plateaus
 * Colorado Plateau
 * in the "Four Corners" region
 * roughly circular area
 * 500 kilometers across
 * much of plateau above sea level
 * [[image:ScanGear_CS.jpg width="237" height="251" caption="The three types of stress and their affects"]]
 * [[image:ScanGear_CS.jpg width="237" height="251" caption="The three types of stress and their affects"]]