Answer:
Seafloor spreading, a geological process in which tectonic plates splits from each other.
Explanation:
Seafloor spreading and other tectonic activity processes are the results of mantle convection, a slow churning motion of the Earth's mantle. As two tectonic plates slowly separate, molten material rises up from within the mantle to fill the opening. Seafloor spreading results in the rock samples near ocean ridges being younger than rocks at the deep sea trenches.
