How Do Trenches Form - Trenches are formed by subduction, a geophysical process in which two or more of earth's tectonic plates. Web trenches are formed by subduction, a geophysical process in which two or more of earth's tectonic plates. When this happens, the denser. Web a trench forms when an oceanic plate collides with another plate at a convergent boundary.
Web trenches are formed by subduction, a geophysical process in which two or more of earth's tectonic plates. Trenches are formed by subduction, a geophysical process in which two or more of earth's tectonic plates. When this happens, the denser. Web a trench forms when an oceanic plate collides with another plate at a convergent boundary.