What is the difference between ductile and brittle deformation in rocks, and what factors control which type occurs?
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A
Ductile deformation occurs only in metamorphic rocks; brittle deformation occurs only in sedimentary rocks, regardless of conditions
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B
Ductile deformation involves continuous flow and folding without fracturing; brittle deformation involves fracturing and faulting. Temperature, pressure, strain rate, and rock type control which occurs — higher T and P, slower strain rates, and weaker minerals favor ductile behavior
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C
Ductile deformation only occurs under extensional tectonic regimes; brittle deformation only under compression
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D
Ductile deformation involves cataclastic flow; brittle deformation involves crystal plastic mechanisms such as dislocation glide