Geo 101-009 Exam 4 Study Guide

Deformation and Mountain Building + Earthquakes

most crustal deformation occurs along

plate margins

tensional stresses mean the plate is

pulling apart

compressional stresses means the plate is

being squeezed together

what is the term that describes rocks having an elastic capability?

ductile deformation

dropping a book on dough and the dough flattening is what kind of strain?

plastic strain

dropping a plate on the ground is an example of what kind of strain?

fracture

folds result from which kind of stress and as a result shorten and thicken the crust?

compressional stress

which term describes arched rock layers where the oldest rock is in the center of the fold?

anticline

which term describe downfolds of rock layers where the youngest rock is in the center of the fold?

syncline

when we measure beds and folds, what is the orientation (trend) of layers that are along a horizontal line on a plane called?

strike

when measuring beds and folds, what is the angle of a plane’s slope which form vertical and perpendicular to the strike called?

dip

what term describes fractures in rocks with displacement showing movement along faults and causing the most earthquakes?

fault

this kind of dip-slip fault is tensional and the hanging wall moves down relative to the footwall which accommodates lengthening and extensional forces.

normal fault

this kind of dip-slip fault is compressional and the hanging wall moves up relative to the footwall which accommodates shortening.

reverse fault

which type of strike-slip fault is where the movement of the right side is towards to spectator?

right lateral

which type of strike-slip fault is where the movement of the left side is towards the spectator?

left lateral

these kinds of strike-slip faults make large cuts through the lithosphere and accommodates motion between two crustal plates?

transform fault

true or false: joints are fractures with movement.

false

true or false: earthquakes occur at plate boundaries.

true

fill in the blank: earthquakes are vibrations of the earth produced by the rapid _____ of energy.

(storing or release)

release

the epicenter of an earthquake is directly above or below the focus?

above

this theory explains how a force is applied to rocks until their internal strength is exceeded, so rocks bend and thus store elastic energy until their frictional resistance is overcome at the focus, and then the earthquake “springs back” to its original shape.

elastic rebound theory

strain/stress recovery is

elastic

ductile stress is

plastic

brittle stress is

fracture

the San Andreas Fault in California is an example of which kind of fault?

transform fault

a foreshock is _____ the earthquake and the aftershock is _____ the earthquake. (separate answers with a comma)

before, after

describes the study of earthquakes

seismology

true or false: surface waves cause minimal destruction.

false

which describe the correct seismic wave behavior from arrives first to last?

P > S > L > R

true or false: the farther the waves travel, the greater the P-S time interval.

true

primary (P) waves can travel through…

solids, liquids, and gases

secondary (S) waves can only travel through…

solids

P waves are _____ while S waves are _____. (separate answers with comma)

pushing/pulling, shaking

true or false: waves travel quickly through dense rocks

false