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How do igneous rocks form?

A. Compaction and cementation of sediment
B. Cooling of molten lava or magma
C. Heating and added pressure to existing rock
D. Evaporation of seawater

User Rick Bross
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2 Answers

7 votes
C. Heating and added pressure to existing rock.
User Flashpunk
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1 vote

Answer:

C. Cooling of molten lava and magma

Step-by-step explanation:

The rocks under the surface of earth are heated at very high temperatures. They melt at these high temperatures and create magma. Magma composition depends upon the elements of the parent rocks. It also contains gases. The elements of earth crust are main elements of magma. When this magma is cooled and hardened, igneous rocks are produced. The formation of these rocks depends upon the following factors:

i) Temperature

ii) Pressure

iii) Water

iv) Parent rock composition

User Mike Sokolov
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