Astronomers studying the planet of Acer have detected igneous rock under its surface. One astronomer makes a claim that some of the material that this igneous rock formed from used to be in sedimentary rock on the surface of Acer. If the scientist is correct, how could the sedimentary rock have become igneous rock?

Answer 1

If the claim is correct that some of the material from sedimentary rock on the surface of Acer is now part of the igneous rock detected beneath its surface, the process that could have caused this transformation is called the rock cycle, specifically involving metamorphism and magmatism.

1. Sedimentation: Initially, minerals from pre-existing rocks, including igneous or metamorphic rocks, would break down due to weathering and erosion, forming sediments that accumulate in layers. Over time, these sediments compact and cement together to form sedimentary rock.

2. Metamorphism: If the sedimentary rock is subjected to increased pressure and temperature, it can undergo metamorphism, becoming metamorphic rock. This can occur due to tectonic activity, such as the collision of tectonic plates that increases pressure and temperature conditions in the crust.

3. Melting and Magmatism: If enough heat is applied (potentially from deep within the planet or from nearby magma), the metamorphic rock could partially or completely melt, resulting in molten rock or magma.

4. Solidification: When this magma rises to the surface and cools, it solidifies to become igneous rock. If the magma cools quickly, it could form volcanic rock; if it cools slowly beneath the surface, it may form intrusive igneous rock.

Thus, the process from sedimentary through metamorphic to igneous involves multiple geological processes, including compaction, heating, and melting, all of which could allow for the transformation of sedimentary material into igneous rock beneath the surface of Acer.