The age of one thing compared to another

Any evidence of an organism that lived in the past

A natural, nonliving material that makes up rock

Uses 1-10; the higher the number, the harder the rock

An energy source formed from the remains of plants/animals that died a long time ago (coal, oil, natural gas)

A "fire made rock" formed when melted magma or lava cools

How fast water passes through soil (sandy soil with large pore spaces is very permeable)

The material found at the bottom of most soil profiles

Decayed (nonliving) plant and animal material found in soil

A view of the different horizons from the surface down to the bedrock

A rock formed from another kind of rock under heat and pressure

A resource (material) that can be replaced

A layer of soil

A resource (material) that cannot be easily replaced; when used up, it's gone forever (example: fossil fuels)

Soil that is rich in humus and minerals

The process where rocks continually change over a long period of time from one type of rock to another

A rock formed when small pieces of matter are pressed together (cemented) into layers; (fossils are usually found in this rock)