Rocks and the Rock

Cycle

•Rock is a solid material made up of minerals or other substances.

•Most of Earth’s rocks are made up of about 20 common minerals, called rock-forming minerals.

•The color of the rock depends on the color of the minerals that make up the rock.

•To a geologist, texture refers to the size, shape, and arrangement of a rock’s grains.A rock grain is one of the

particles that make up a rock•Geologists classify rocks into three major groups by how they are formed.

•Igneous rock forms when lava or magma cools and hardens.

•Igneous rock formed from magma beneath the Earth’s surface is called intrusive.

Intrusive – Inside the Earth

•Igneous rock formed from lava above the Earth’s surface is called extrusive.

Extrusive – Exited the Earth

•Sedimentary rock forms when particles of rock and other material are pressed and stuck together.

•Compaction (pressed)

•Cementation (stuck)

•Any rock can become Sedimentary Rock

•There are three major kinds of sedimentary rock

Clastic – Organic – Chemical

•A sedimentary rock that you can see the particles of rock that have been stuck together is called a clastic rock.

•A sedimentary rock that formed from the remains of plants and animals is called organic rock.

•A sedimentary rock that forms when dissolved minerals come out of solution is called a chemical rock.

•Metamorphic rock forms from high heat and pressure beneath the surface of the Earth.

•Any type of rock can become a metamorphic rock.

•The rock cycle is a series of processes that change rocks from one kind to another kind.

Explain the Rock Cycle

Begins sedimentary metamorphic igneous

How It Changes

Ends metamorphic sedimentary sedimentary