Historical Geology for 5-4

Front

What type of rock forms fossils?

Back

Sedimentary rocks are the only type of rock that can form fossils, as they are formed from the accumulation of sediment and organic material.

Front

What process is most likely to lead to fossil formation?

Back

Being buried quickly is crucial for fossil formation, as it protects remains from decay and scavengers.

Front

What is a half-life in geology?

Back

A half-life is the time required for half of the radioactive isotopes in a sample to decay.

Front

What percentage of the original isotope is left after 2 half-lives?

Back

25% of the original isotope remains after 2 half-lives.

Front

What does finding fossils of aquatic fish and plants in an area indicate about its past?

Back

It indicates that the area was once covered by ocean.

Front

What are the four main types of rocks?

Back

The four main types of rocks are igneous, sedimentary, metamorphic, and volcanic.

Front

How do sedimentary rocks form?

Back

Sedimentary rocks form through the accumulation and compaction of mineral and organic particles.

Front

What is the significance of fossils in understanding Earth's history?

Back

Fossils provide evidence of past life forms and environmental conditions, helping scientists reconstruct Earth's history.

Front

What is the difference between intrusive and extrusive igneous rocks?

Back

Intrusive igneous rocks form from magma that cools slowly beneath the Earth's surface, while extrusive igneous rocks form from lava that cools quickly on the surface.

Front

What is the role of sediment in fossil formation?

Back

Sediment helps to bury and preserve remains, preventing decay and allowing for fossilization.