Question

A geologist is studying a massive rock outcrop. The texture of the rock is coarse-grained with large round grains. The geologist determines that the rock probably formed when lava cooled on Earth's surface What type of rock has the geologist identified?

Answer 1

The geologist has identified an extrusive or volcanic igneous rock based on the coarse-grained texture and the fact that the rock formed when lava cooled on the Earth's surface.

Step-by-step explanation:

The geologist has identified an extrusive or volcanic igneous rock based on the coarse-grained texture and the fact that the rock formed when lava cooled on the Earth's surface. Extrusive igneous rocks form when lava cools quickly on the surface, resulting in small grains. In contrast, intrusive or plutonic igneous rocks form when magma cools slowly deep within the Earth, resulting in large grains. In this case, the presence of large round grains indicates that the rock is an extrusive igneous rock.