Geologic Time

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What is the Law of Superposition?

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The Law of Superposition states that in undisturbed sedimentary rock layers, the oldest layers are at the bottom and the youngest layers are at the top.

Tags

NGSS.MS-ESS1-4

Front

How do geologists determine the relative age of rock layers?

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Geologists determine the relative age of rock layers by examining their position in relation to one another, using principles like the Law of Superposition.

Tags

NGSS.MS-ESS1-4

Front

What is radioactive dating?

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Radioactive dating is a method used to determine the age of rocks and fossils by measuring the amount of radioactive material and its decay products.

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NGSS.HS-PS1-8

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What is sedimentation?

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Sedimentation is the process by which particles settle out of a fluid, forming layers of sediment over time.

Tags

NGSS.MS-ESS1-4

NGSS.MS-ESS2-2

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What is the significance of fossils in geology?

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Fossils help geologists determine the relative ages of rock layers and can provide information about the environment in which the rocks were formed.

Tags

NGSS.MS-ESS1-4

NGSS.MS-LS4-1

Front

What is the difference between relative age and absolute age?

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Relative age is the age of a rock layer compared to other layers, while absolute age is the actual age of a rock or fossil, often determined through radioactive dating.

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What is an igneous rock?

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Igneous rock is formed from the cooling and solidification of molten rock (magma or lava).

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What does the term 'upwelling' refer to in geology?

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Upwelling refers to the process where magma rises from the Earth's mantle to the surface, often forming igneous rock.

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What is the role of sedimentary layers in understanding Earth's history?

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Sedimentary layers provide a record of Earth's history, including changes in environment, climate, and life forms over time.

Tags

NGSS.MS-ESS1-4

NGSS.MS-LS4-1

Front

How can geologists use rock layers to understand the formation of canyons?

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Geologists can compare the ages of rock layers in a canyon to determine the time period over which the canyon formed.

Tags

NGSS.MS-ESS1-4

NGSS.MS-ESS2-2