9 multiple choice 5 points the amount of magn...
9 multiple choice 5 points the amount of magnesium and iron ______. decreases in darker - colored rocks increases in lighter - colored rocks increases in rocks that are high in silicon increases in mafic rocks 10 multiple answer 5 points which two of these would be demonstrated in the himalayan mountains? contact metamorphism regional metamorphism schistose metamorphism subterranean metamorphism hydrothermal metamorphism gneissic metamorphism metamorphism at convergent plate boundaries
Answer
# Brief Explanations:
For question 9: Mafic rocks are rich in magnesium and iron. Dark - colored rocks are often mafic and have higher amounts of these elements. Lighter - colored rocks are usually felsic with less magnesium and iron. Rocks high in silicon are felsic and have lower magnesium and iron content.
For question 10: The Himalayan Mountains are formed at convergent plate boundaries and are an example of regional metamorphism due to large - scale tectonic forces.
# Answer:
9. D. increases in mafic rocks
10. B. regional metamorphism, G. metamorphism at convergent plate boundaries