Rocks

What is weathering?

the breaking down of rocks

What is erosion?

The movement of broken rock to a new location.

3 types of weathering.

Physical, chemical, biological.

What is physical weathering?

rocks breaking without chemical change

What is freeze-thaw weathering?

ater enters cracks → freezes → expands → breaks rock.

What is biological weathering?

plants or organisms break rocks

What is exfoliation?

rock peeling in layers due to heating and cooling.

How are sedimentary rocks formed?

sedimentation → compaction → cementation.

What is sedimentation?

Particles settling down.

What is compaction?

squeezing sediments

What is cementation?

gluing sediments

Give examples of sedimentary rocks.

imestone, sandstone, shale.

why do sedimentary rocks contain fossils?

They form in layers that trap organisms.

What are metamorphic rocks?

ocks changed by heat and pressure.

what causes metamorphic rocks to form?

Heat and pressure inside the Earth.

Do metamorphic rocks melt?

They do not melt, but the minerals they contain are changed chemically, forming metamorphic rocks.

What are igneous rocks?

Rocks formed when molten rock cools and solidifies.

What are the 2 types of igneous rocks?

Extrusive and intrusive.

what are extrusive rocks?

Extrusive rocks are formed when magma reaches the Earth’s surface and cools quickly. small crystals

What are intrusive rocks?

Intrusive rocks are formed when magma cools slowly beneath the Earth’s surface. This slow cooling forms large crystals, such as in granite.