地球科学问题1.Manyrocksproducedbycontactmetamorphismshowlittleornofoliationbecause:(a)verylittledeformationaccompaniesthemetamorphism.(b)thistypeofmetamorphismoccursatveryhighpressures(c)thistypeofmetamorphismoccu

Question

地球科学问题
1.Many rocks produced by contact metamorphism show little or no foliation because:
(a) very little deformation accompanies the metamorphism.
(b) this type of metamorphism occurs at very high pressures
(c) this type of metamorphism occurs at very low pressures
(d) none of the original minerals recrystallized during the metamorphism.
2.Regional metamorphism occurs when:
(a) sediments are buried to great depths.
(b) magma moves up through the earth’s crust,toward the surface.
(c) brittle rocks are intensely deformed at very high pressures.
(d) sediments are melted at very high temperatures.

Answer 1

第一题是c,成层的结构是高压下,压力梯降的反映,接触变质更多的是高温影响产生的重结晶.
第二题是貌似也是c,只有a和d不能确定一定是区域变质.