EARTH SCIENCE
EARTHQUAKES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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when rocks are pulled apart
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when rocks fold or break
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a rock deep underground is pushed by weight above it, rock cannot move, it cannot deform
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parallel forces move in opposite directions
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Detailed explanation-1: -A deeply buried rock is pushed down by the weight of all the material above it. Since the rock cannot move, it cannot deform. This is called confining stress.
Detailed explanation-2: -Confining stress comes from the weight of all the overlying rock. This weight pushes down on a deeply buried rock. The rock is being pushed in from all sides, which compresses it. The rock will not deform because there is no place for it to move.
Detailed explanation-3: -Compression: Stress which causes rock to squeeze or push against other rock. Tension: Stress which occurs when rock pulls apart or gets longer.
Detailed explanation-4: -Stress is a force acting on a rock per unit area. It has the same units as pressure, but also has a direction (i.e., it is a vector, just like a force). There are three types of stress: compression, tension, and shear.