GENERAL GEOLOGY (EQUAKE)

Question 1

catastrophic magnitude 7.0 Mw earthquake struck

Answer 1

January 12 2010

Question 2

Epicenter of such earthquake

Answer 2

25 km of Port-au-Prince

Question 3

Depth

Answer 3

10km

Question 4

Ground shaking caused by sudden rapid omvement of one block of rock slipping past another along factures in earth’s crust

Answer 4

Earthquake

Question 5

Fractures on Earth’s crust which are locked due to the enormous confining pressure exerte by the overlaying crust except for brief abrupt movements when sudden slippage

Answer 5

Faults

Question 6

The location where slippage of fault begins

Answer 6

hypocenter or focus

Question 7

The point on earth’s surface directly above the focus

Answer 7

epicenter

Question 8

A form of energy that travels through the lithosphere and earth’s interior that causes the material that transmit such energy to shake

Answer 8

Seismic Waves

Question 9

How many strong equakes mag 7 or greater happen every year?

Answer 9

15

Question 10

Who first studied the actual mechanism of earthquake generation

Answer 10

H.F. Reid from John Hopkins University

Question 11

What earthquake served as the model of such study

Answer 11

1906 San Fancisco Earthquake

Question 12

What fault moved in the said earthquake

Answer 12

San Andres Fault

Question 13

What plates moved?

Answer 13

Pacific and N. American

Question 14

Earthquake generation according to Reid

Answer 14

1) Differential stress due to tectonic plates movement slowly bends crustal rocks on both sides
2) Once strength of rocks is exceeded, slippage occur along the fault to produce equake
3) The rocks return to their original shape but in a new location

Question 15

this prevents the fault from fracturing and slipping

Answer 15

Frictional Resistance

Question 16

How is friction enhanced?

Answer 16

Irregularities that occur along fault surface

Question 17

The springing back of rock to its original, stress-free shape after slippage

Answer 17

Elastic Rebound

Question 18

Lesser magnitude quakes that follow a large equakes due to the crust along the fault surface adjusting to the displacement caused by the main shock

Answer 18

Aftershocks

Question 19

.

Answer 19

Foreshocks

Question 20

theory wc states that large slabs of Earth’s lithosphere are continually grinding past one another

Answer 20

Plate tectonics

Question 21

Seismometer

Answer 21

Instrument that record vibration

Question 22

Seismograph

Answer 22

Resulting graph

Question 23

Body waves

Answer 23

Emanate from the focus and travel in all direction through the body of the Earth

Question 24

P wave

Answer 24

?Compressing and expanding movemnt
?Depends on the incompressibility (Bulk’s Modulus) and Rigidity (Shear Modulus)
?HIghestVelocity and will always reach seismographs first

Question 25

S Wave

Answer 25

?Perpendicular shearing movement to the direction of the wave
?Depends on the resistance to shearing of a material (rigidity)
?Will always arrive second to Pwave

Question 26

Surface Waves

Answer 26

?Do not travel through the Earth
?Travel along paths that are parallel to the Surface of the Earth
?Slower than S waves

Question 27

Love Waves

Answer 27

?Side to Side perpendicular to wave direction

Question 28

Rayleigh Waves

Answer 28

?Counterclockwise eliptical up and down

Question 29

P-wave ShadowZone

Answer 29

Zone on the opposite side of earth from an earth focus that receive NO WAVES because waves are REFRACTED INWARD due to sudden decrease in velocity of Pwave at the boundary

Question 30

S-wave shadow Zone

Answer 30

Zone on the opposite side of Earth from the focus where there is no S-wave reaching the area due to non passing of S-wave through the core