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Civil Engineering · Q30

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Engineering and GATE · Civil Engineering · question 30

Q30

Gneiss is obtained from

A.
Igneous rocks
B.
Metamorphic rocks
Answer
C.
Sedimentary rocks
D.
Sedimentary metamorphic rocks

Answer: Option B

Solution

Answer: Option B
Solution:
Gneiss is a type of rock that forms through a process of metamorphism. Let’s look at the options:

Option A: Igneous rocks → Incorrect. Igneous rocks are formed from the cooling and solidification of molten material, such as magma or lava. Gneiss is not derived from igneous rocks.

Option B: Metamorphic rocks → Correct. Gneiss is a metamorphic rock that is formed when granite or other rocks undergo high pressure and temperature, leading to the formation of distinct bands.

Option C: Sedimentary rocks → Incorrect. Sedimentary rocks form from the deposition of materials over time, such as sand, silt, and clay. Gneiss does not come from sedimentary processes.

Option D: Sedimentary metamorphic rocks → Incorrect. Gneiss is specifically a metamorphic rock, not a combination of sedimentary and metamorphic types.

Therefore, the correct answer is Option B: Metamorphic rocks, as gneiss is derived from the metamorphism of other rocks, typically granite.