Examkin

Question

Difficulty: EasyRocks, Minerals, and Soil

When sedimentary limestone is subjected to intense heat and tectonic pressure deep within Earth's crust, its calcite minerals recrystallize to form marble. Based on this transformation process, marble is classified as which type of rock?

  1. A
    Igneous rock
  2. Metamorphic rockAnswer
  3. C
    Sedimentary rock
  4. D
    Extrusive volcanic rock

Answer

Metamorphic rock
Metamorphic rocks develop when pre-existing sedimentary, igneous, or older metamorphic rocks are altered by intense heat and pressure within Earth's crust without melting. When limestone undergoes this process, its calcite grains recrystallize into a denser, interlocking crystalline texture, forming marble.

Step-by-Step Solution

1
Identify the parent material and geological processes described in the question.
Limestone (a sedimentary rock) is subjected to intense underground heat and pressure without melting, causing recrystallization into marble.
Identifying the formation mechanism determines the rock classification.
2
Match the formation mechanism to the correct major rock classification.
Rocks created by altering pre-existing rocks through heat and pressure are categorized as metamorphic rocks.
Metamorphism refers specifically to solid-state mineral and textural alterations under elevated temperatures and pressures.

Key Concept

Metamorphic rock formation and classification through heat and pressure alteration
Estimated Time:45s
Rate this question

Topics

Rocks, Minerals, and Soil

More questions from this topic