EARTH SCIENCE
EARTHQUAKES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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California is constantly pounded by waves from the Pacific Ocean
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California is located on a solid granite sheet
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California is built on ancient sand bars from ancient oceans
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California is located on a tectonic plate boundary
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Detailed explanation-1: -The Pacific Plate (on the west) slides horizontally northwestward relative to the North American Plate (on the east), causing earthquakes along the San Andreas and associated faults. The San Andreas fault is a transform plate boundary, accomodating horizontal relative motions.
Detailed explanation-2: -These plates are always moving apart, bumping, or sliding past each other at about the same speed that your fingernails grow. Earthquakes usually occur where two plates are running into each other or sliding past each other.
Detailed explanation-3: -Since the formation of the San Andreas Fault system 25-30 million years ago, the juxtaposition of the Pacific and North American plates has formed many faults in California that accommodate lateral motion between the plates.
Detailed explanation-4: -The San Andreas Fault System, which crosses California from the Salton Sea in the south to Cape Mendocino in the north, is the boundary between the Pacific Plate (that includes the Pacific Ocean) and North American Plate (that includes North America).
Detailed explanation-5: -Summary. Transform fault earthquakes have shallow focus because the plates meet near the surface. The San Andreas Fault is actually a fault zone made up of a number of other active faults.