An introduction to geology
An introduction to geology

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An introduction to geology

2.16 What type of rock is oceanic crust?

See if you can answer this question by completing the activity below.

Activity 2.3 Oceanic crust

Timing: Allow about 2 minutes

Is oceanic crust igneous, metamorphic or sedimentary?







The correct answer is a.


The answer is igneous. It’s all made in volcanoes at the spreading centres, and cools from a molten state (the definition of igneous). The sea floor does get covered in sediment over time which is sedimentary, but the oceanic crust that it forms on is always igneous.


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