EARTH SCIENCE
STRUCTURAL GEOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Brittle deformation involves bending of rocks.
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Brittle deformation occurs in rocks experiencing higher temperatures
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Brittle deformation involves sudden breaking of rocks.
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Brittle deformation occurs in rocks experiencing lower temperatures.
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Detailed explanation-1: -Ductile Deformation = rock breaks while undergoing plastic strain. Pressure, temperature and rate of deformation determines brittle versus ductile deformation. Brittle deformation occurs commonly at the surface of the earth (lower temperature) – ductile deformation occurs at depth (higher temperatures).
Detailed explanation-2: -Brittle deformation is where rock fractures once its strength is surpassed, while ductile deformation is where a rocks size and shape changes without fracturing.
Detailed explanation-3: -Brittle deformation is when rocks fail as rigid solids (Fig. 7.1A). The rocks will break, rather than bend, under these conditions to produce fractures. Brittle deformation occurs along discrete planes in the rock instead of involving the rock body as a whole.
Detailed explanation-4: -Elastic deformation is a reversible deformation, ductile deformation is irreversible where brittle deformation causes the rock to break.
Detailed explanation-5: -Fig. 2.1. The three modes of brittle deformation or fracture: mode I = opening, mode II = sliding, mode III = tearing.