Question

John finds a rock that contains large, light-colored mineral crystals. the rock shows no sign of being altered by heat or pressure. what can john infer about the rock?
A. the rock is formed below earths surface.
B. the rock formed from hardened magma.
C. the rock underwent lithification.
D. the rock underwent metamorphism.

Answer 1

From the above statement, John can infer that the rock underwent metamorphism and also is not altered by heat or pressure.

Explanation:

• Metamorphic rock is an igneous sedimentary rock and although when put through heat the rock becomes hot but does not alter its shape or melt. If the rock melts then it is only an igneous rock and not a sedimentary one.
• During metamorphism, the chemical and the mineral content of prolith are changed due to changes in the environment based on physical and chemical conditions.
• Even though the rocks remain solid, fluid is present between the macroscopic spaces.
• This gives "The Geologist" accurate information of what happens beneath the earth during the formation of mountains.
• Metamorphic rocks are like probes that go down the earth and comes back giving information of what happens underneath the surface.