Geological History of Earth

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What is a fossil?

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A fossil is the preserved remains or trace of an organism.

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Where are the youngest fossils found in the fossil record?

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The youngest fossils are found in the top layer of the fossil record.

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What are rock strata?

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Rock strata are the sedimentary layers of rock in Earth.

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What is a fossil record?

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The fossil record includes the mineralized remains of organisms and the rock layers in which they are found.

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What does the Law of Superposition state?

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The Law of Superposition states that within the layers of sedimentary rock, the youngest layer is at the top, and each layer below is older.

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What is geological time scale?

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The geological time scale is a system of chronological dating that relates geological strata to time.

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What is stratigraphy?

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Stratigraphy is the study of rock layers (strata) and layering (stratification).

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What are eras in geological history?

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Eras are large divisions of geological time that are made up of periods.

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

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Fossils provide evidence of past life and help scientists understand the evolution of organisms and changes in the environment.

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How do fossils form?

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Fossils form when organisms are buried by sediment, which hardens into rock over time, preserving the shape of the organism.