RLNI+2.1

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Vocabulary
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 * Earthquake**: shaking and trembling that results from the movement of rock beneath earth's surface
 * Stress**: a force that acts on rock to change its shape of volume
 * Shearing**: causes rock to break and slip apart or to change its shape
 * Tension**: pulls on crust, stretching rock so that it becomes thinner in the middle
 * Compression**: a stress force which squeezes rock until it folds or breaks
 * Deformation**: any change in the volume or shape of earth's crust
 * Fault**: breaks in earth's crust where slabs of crust slip past each other
 * Strike Slip Fault**: rocks on either side of the fault that slip past each other sideways with little up and down motion
 * Normal Fault**: at an angle, so one block of rock lies above the fault while the other block lies below the fault
 * Reverse Fault**: same structure as normal fault, but blocks move in opposite directions
 * Fault Block Mountain**: forms when normal fault uplift a block of rock
 * Folds**: bends in rock that forms when compression shortens and thickens parts of earth's crust
 * Anticline**: fold in rock that bends upward into an arch
 * Syncline**: fold in rock that bends downward in the middle to form a bowl
 * Plateau**: large area of flat land elevated high above sea level

**Stress in the Crust**

 * movement of earth's plate creates powerful force
 * Types of Stress**
 * shearing
 * causes rock to break and slip apart or to change its shape
 * tension
 * makes the middle of rock thinner by stretching it
 * compression
 * squeezes rock until it folds or breaks

**Kinds of Faults**

 * faults usually occur along plate boundaries, where forces of plate motion compress, pull, or shear the crust so much that the crust breaks
 * strike slip fault
 * created by shearing
 * forms transform boundary between two plates
 * the San Andreas fault is a strike slip fault that is a transform boundary
 * normal fault
 * caused by tension
 * at an angle so one block of rock is above the fault while the other block lies below the fault
 * half of the fault that lies above is called the hanging wall
 * the other half of the fault is the footwall
 * when movement occurs, hanging wall slips downward
 * the Rio Grande is a rift valley where normal faults occur
 * reverse fault
 * produced by compression forces
 * same structure as normal fault
 * the Appalachian Mountains were partly produced by reverse faults
 * Friction Along Faults**
 * force that is against the motion of a surface as it moves across another surface
 * how rocks move along a fault depends on how much friction there is between the opposite sides of the fault

Mountain Building

 * fault movement can change a flat plain into a towering mountain range in millions of years
 * mountains formed by faulting
 * when normal faults lift up a block of rock a fault block mountain forms
 * an example of a fault block mountain range is the Sierra Nevada
 * mountain formed by folding
 * two plates colliding can cause compression and folding of the crust
 * the Himalayas and the Alps are some of the world's largest mountain ranges
 * folding rocks can fracture and produce faults
 * anticlines and synclines
 * anticline
 * fold in rock that bends upward into an arch
 * Black Hills of South Dakota
 * syncline
 * fold in rock that bends downward that forms a bowl
 * Illinois Basin
 * plateaus
 * mountains and plateaus are raised by the same forces
 * many different flat layers
 * wider than it is tall
 * the Colorado Plateau