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
a.
igneous
b.
sedimentary
c.
metamorphic
The correct answer is a.
Discussion
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.