Based on geological classification, which of the following sequences correctly represents an igneous rock, a sedimentary rock and its corresponding metamorphic derivative respectively?
- AGranite, Limestone, Quartzite
- BBasalt, Sandstone, Marble
- CGranite, Limestone, MarbleCorrect
- DSyenite, Shale, Slate
Solution
Concept
Geological classification and metamorphism of rocks
Formula
Limestone + Heat/Pressure -> Marble
Step-by-step solution
1. Geological classification divides rocks into igneous, sedimentary, and metamorphic types. 2. Granite is an intrusive igneous rock formed by cooling magma. 3. Limestone is a sedimentary rock formed from accumulated calcium carbonate deposits. 4. Marble is the metamorphic derivative formed when limestone undergoes recrystallization under intense heat and pressure. Answer: C
Explanation
Granite is an intrusive igneous rock formed by the slow crystallization of magma deep within the Earth's crust. Limestone is a sedimentary rock composed primarily of compacted calcite from marine deposits, and when subjected to geological metamorphism through heat and pressure, it recrystallizes into marble. Thus, Granite, Limestone, and Marble correctly represent an igneous rock, a sedimentary rock, and its metamorphic derivative.
Why the other options are wrong
A) Quartzite is the metamorphic derivative of sandstone, not limestone. B) Marble is derived from limestone, whereas sandstone metamorphoses into quartzite. D) Slate derives from shale, but Granite, Limestone, and Marble is the primary textbook sequence.
Shortcut
Granite (Igneous), Limestone (Sedimentary) -> Marble (Metamorphic of Limestone).
Common mistake
Assuming Quartzite derives from Limestone (Quartzite derives from Sandstone) or Marble derives from Sandstone.
Correct answer: C) Granite, Limestone, Marble