8.2 Vocab

The idea that the universe, including Earth and its ecosystems, have a very, very long history, most of which occurred before humans were able to record that history directly through observations and writing.

• deep time
• absolute dating
• igneous rock
• fossil

The preserved remains, impressions, or traces of a once-living organism from the past.

• metamorphic rock
• strata
• fossil
• erosion

The solid rock that is typically covered by loose surface material like soil.

• deep time
• relative dating
• bedrock
• strata

Rocks formed by the accumulation of sediments that become compacted under their own weight and cemented together through chemical reactions.

• metamorphic rock
• relative dating
• igneous rock
• sedimentary rock

A rock that is formed when an existing rock (either sedimentary or igneous) is changed by extreme heat and pressure.

• metamorphic rock
• igneous rock
• sedimentary rock
• erosion

Rocks that form from cooled and hardened melted earth material such as lava and magma.

• fossil
• metamorphic rock
• sedimentary rock
• igneous rock

The layers in a sedimentary rock- due to different sediments being deposited at different times.

• strata
• bedrock
• relative dating
• fossil

The age of an object in comparison to other objects based on how they are arranged (e.g. layer a is below layer b. Therefore layer a is older than layer b, but we do not know the exact age of either layer).

• igneous rock
• deep time
• relative dating
• strata

A dating method that lets you know the actual age of rock, for example, rock X was formed 350 million years ago (mya).

• deep time
• erosion
• absolute dating
• relative dating

The action of wind, eater, ice, or other natural processes that removes sediments from one location and moves it somewhere else.

• strata
• deposition
• weathering
• erosion