The rock at oceanic ridges is also somewhat softer because it is hot. At trenches, the crust is thicker and cooler, which allows more strain to accumulate, leading to more earthquakes.Boundaries between tectonic plates are made up of a system of faults. … Hot magma rises from the mantle at mid-ocean ridges, pushing the plates apart. Earthquakes occur along the fractures that appear as the plates move apart.
