The movement of heat in the Earth is governed by Geothermal Theory . Sea floor sediments were relatively thin and thinned towards the mid-ocean ridge. This trend was followed by an increasingly younger-age to the plankton. Accuracy 3 cm. Their presence reflects the fact that belts are underlain by rocks much lighter than those at depth on either side.
New crust is added to the trailing edge of each separating plate.
Crust is basalt and, hence, responsible for the formation of new ocean basins. A spherical earth requires adjustment of a rigid crust. Therefore, offsets in the crust exist termed transform faults. Convergent Boundaries Convergent boundaries are where leading edges of two plates come in contact with each other. Structural features of these zones are varied.