Volcanoes and Earthquakes

Front

Plate Tectonics Noun

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[playt tek-ton-iks]

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Plate Tectonics

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The theory that Earth's outer layer is made of large, solid plates that are in constant, slow motion.

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Example: The image shows Earth's plates moving, explaining how their motion forms mountains and causes earthquakes.

Front

Fossil Noun

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[fos-uhl]

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Fossil

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The preserved remains or traces of ancient organisms, like plants and animals, that are found within layers of rock.

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Example: A fossil of an ancient animal embedded in rock shows how organisms are preserved over time.

Front

Continental Drift Noun

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[kon-tuh-nen-tl drift]

Back

Continental Drift

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The theory that continents have moved slowly over geologic time across Earth's surface, as proposed by Alfred Wegener.

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Example: Arrows show tectonic plates moving, illustrating continental drift.

Front

Pangaea Noun

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[pan-jee-uh]

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Pangaea

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The name given to the single supercontinent that was believed to have existed before the continents drifted apart.

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Example: The image shows Pangaea as a single landmass with labeled continents, illustrating the supercontinent before they drifted apart.

Front

Neptunists Noun

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[nep-too-nists]

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Neptunists

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A group of historical geologists who believed Earth's features were formed by the rise and fall of a global ocean.

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Example: The image shows layers of sediment formed by ancient oceans, illustrating the Neptunist belief in Earth's features shaped by water.

Front

Plutonists Noun

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[ploo-tuh-nists]

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Plutonists

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Historical geologists who believed Earth's features were formed by heat from within the planet, causing volcanoes and earthquakes.

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Example: Magma beneath Earth's surface shows how internal heat forms volcanoes and earthquakes.

Front

Catastrophism Noun

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[kuh-tas-truh-fiz-uhm]

Back

Catastrophism

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The theory that Earth's geological changes occurred suddenly through major, short-lived, and violent events like massive floods.

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Example: A volcano eruption shows sudden geological changes, illustrating catastrophism.

Front

Gradualism Noun

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[graj-oo-uh-liz-uhm]

Back

Gradualism

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The theory that Earth's geological changes are the result of slow, continuous processes occurring over very long periods.

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Example: The image shows tectonic plates moving slowly, causing gradual geological changes.

Front

Uniformitarianism Noun

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[yoo-nuh-fawr-mi-tair-ee-uh-niz-uhm]

Back

Uniformitarianism

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The principle that the same geological processes shaping Earth today also operated in the same manner throughout the past.

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Example: Arrows show tectonic plates moving, causing volcanic eruptions, illustrating uniformitarianism.

Front

Erosion Noun

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[ih-roh-zhuhn]

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Erosion

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The process by which natural forces like water, wind, and ice wear away and transport rock and soil.

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Example: The image shows how a river erodes soil, demonstrating erosion by water.