177k views
4 votes
________________ igneous rocks form from the freezing of lava.

a. Extrusive (volcanic)
b. Intrusive (plutonic)
c. Sedimentary
d. Metamorphic

User Nishkaush
by
8.1k points

1 Answer

5 votes

Final answer:

Extrusive (volcanic) igneous rocks are the correct answer, as they form from the rapid cooling of lava on the Earth's surface, resulting in fine-grained textures.

Step-by-step explanation:

Extrusive (volcanic) igneous rocks form from the freezing of lava after it reaches the Earth's surface. These rocks are characterized by a fine-grained texture because the lava cools relatively quickly in the open air, which does not allow large crystals to form. For example, basalt is a common type of extrusive igneous rock formed from basaltic lava flows.

In contrast, intrusive (plutonic) igneous rocks form when magma cools slowly beneath the Earth's surface, resulting in a coarse-grained texture as larger crystals have time to develop. Granite is a well-known example of an intrusive igneous rock.

Sedimentary rocks and metamorphic rocks are formed through different processes involving deposition, cementation, and alteration of pre-existing rocks through heat and pressure, respectively, but are not the correct answers for rocks formed by the freezing of lava.

User Evangelos
by
7.9k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories