Science Olympiad Dynamic Planet Practice Test

What is the scientific term for the process where the oceanic crust is pushed down into the mantle?

1. Subduction process

2. Seafloor spreading

3. Plate tectonics

4. Magma evolution

The correct answer is: Subduction process

The oceanic crust being pushed down into the mantle is known as the subduction process. This geological phenomenon occurs where two tectonic plates collide, typically involving a denser oceanic plate being forced beneath a lighter continental plate or another oceanic plate. The subducted plate descends into the mantle due to differences in density, leading to various geological activities including the formation of deep ocean trenches, volcanic arcs, and earthquake activity. In contrast, seafloor spreading refers to the process where new oceanic crust is formed at mid-ocean ridges as tectonic plates move apart. Plate tectonics is a broader term that encompasses the movement and interactions of all tectonic plates on Earth, including processes like subduction and seafloor spreading. Magma evolution pertains to the processes that lead to the formation and differentiation of magma, but it does not specifically describe the action of oceanic crust being pushed into the mantle. Hence, the correct answer accurately identifies the specific process of oceanic crust subduction.