CSS - PMS - CCE - PCS - Geography
Earthquakes
Tsunamis can be generated by:
A. Large undersea earthquakes with vertical seafloor displacement
B. Every small inland earthquake
C. Only wind
D. Only tides
Correct Answer: A
Sudden displacement of the seafloor can move a large water column.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Earthquake-induced landslides are favored by:
A. Steep unstable slopes
B. Flat solid bedrock only
C. Deep oceans only
D. No shaking
Correct Answer: A
Ground acceleration can destabilize slopes and trigger mass movement.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Liquefaction is most likely in:
A. Loose, water-saturated sediment
B. Massive dry granite
C. Solid bedrock only
D. Dry desert pavement
Correct Answer: A
Strong shaking can raise pore-water pressure and reduce sediment strength.
CSS - PMS - CCE - PCS - Geography
Earthquakes
A foreshock is:
A. An earthquake preceding a larger mainshock in the same area
B. Any aftershock
C. A tsunami
D. A volcanic tremor only
Correct Answer: A
It is identified as a foreshock only retrospectively after a larger event.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Aftershocks are:
A. Smaller earthquakes following a mainshock in the affected region
B. Waves before a quake
C. Volcanic eruptions only
D. Tsunamis
Correct Answer: A
Aftershocks reflect post-mainshock stress adjustment.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Elastic rebound theory explains:
A. Sudden fault slip after strain accumulation
B. Daily tides
C. Rock crystallization
D. River meandering
Correct Answer: A
Rocks deform elastically until frictional resistance is overcome and the fault slips.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Strike-slip faults involve mainly:
A. Horizontal motion
B. Vertical-only motion
C. Melting
D. Deposition
Correct Answer: A
Blocks slide laterally past one another along strike-slip faults.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Reverse and thrust faults are mainly associated with:
A. Compression
B. Extension
C. Only shear without compression
D. Weathering
Correct Answer: A
Compressional shortening drives reverse and thrust faulting.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Normal faults are mainly associated with:
A. Extension
B. Compression
C. No stress
D. Only volcanism
Correct Answer: A
Crustal extension causes the hanging wall to move down relative to footwall.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Most earthquakes occur along:
A. Faults and plate boundaries
B. River channels only
C. Desert dunes
D. Coastlines regardless of tectonics
Correct Answer: A
Tectonic stress concentrates on faults, especially near plate boundaries.
CSS - PMS - CCE - PCS - Geography
Earthquakes
A one-unit magnitude increase corresponds to roughly:
A. 32 times more energy release
B. 2 times energy
C. 10 times energy exactly
D. 1000 times energy
Correct Answer: A
Seismic energy scales approximately as 10^1.5 per magnitude unit, about 31.6.
CSS - PMS - CCE - PCS - Geography
Earthquakes
A one-unit increase in earthquake magnitude corresponds to about:
A. 10 times greater recorded wave amplitude
B. 2 times amplitude
C. 1000 times amplitude exactly
D. No amplitude change
Correct Answer: A
Magnitude scales are logarithmic; one unit is a factor of ten in amplitude.
CSS - PMS - CCE - PCS - Geography
Earthquakes
The older Richter/local magnitude scale was originally based on:
A. Recorded wave amplitude corrected for distance
B. Casualty count
C. Fault colour
D. Weather
Correct Answer: A
Local magnitude uses logarithmic seismic amplitude measurements.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Moment magnitude (Mw) is based on:
A. Seismic moment
B. Only felt reports
C. Air pressure
D. Tsunami height only
Correct Answer: A
Mw derives from seismic moment, related to rigidity, rupture area and slip.
CSS - PMS - CCE - PCS - Geography
Earthquakes
The Modified Mercalli scale is a scale of:
A. Intensity
B. Magnitude
C. Mineral hardness
D. Wind speed
Correct Answer: A
MMI classifies observed earthquake effects from I to XII.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Earthquake intensity measures:
A. Effects and shaking at a particular location
B. Total energy only
C. Fault length only
D. Plate speed
Correct Answer: A
Intensity varies spatially according to observed shaking/damage.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Earthquake magnitude measures:
A. Size/energy-related amplitude of the event
B. Observed damage at one place only
C. Population exposed
D. Depth only
Correct Answer: A
Magnitude is an instrumental measure related to seismic-wave amplitude and source size.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Rayleigh waves produce:
A. Rolling, elliptical ground motion
B. Only compression
C. No vertical motion
D. Only sound
Correct Answer: A
Rayleigh-wave particle motion is retrograde/elliptical in a vertical plane.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Love waves involve mainly:
A. Horizontal shear motion
B. Compressional vertical motion only
C. Fluid flow
D. Magnetic oscillation
Correct Answer: A
Love waves shear the ground horizontally.
CSS - PMS - CCE - PCS - Geography
Earthquakes
Surface waves generally cause:
A. Strong shaking near Earth's surface
B. No damage
C. Only core motion
D. Only magnetic changes
Correct Answer: A
Love and Rayleigh waves often have large amplitudes and are damaging.