gravitational pull is the primary force that generates ridge push.
gravitational pull is the primary force that generates ridge push.
what is the primary force that generates ridge push?
gravitational pull
ridge push or sliding plate force is a proposed driving force for plate motion in plate tectonics that occurs at mid-ocean ridges as the result of the rigid lithosphere sliding down the hot, raised asthenosphere below mid-ocean ridges. although it is called ridge push, the term is somewhat misleading; it is actually a body force that acts throughout an ocean plate, not just at the ridge, as a result of gravitational pull. the name comes from earlier models of plate tectonics in which ridge push was primarily ascribed to upwelling magma at mid-ocean ridges pushing or wedging the plates apart.
ridge push
early models of plate tectonics, such as harry hess's seafloor spreading model, assumed that the motions of plates and the activity of mid-ocean ridges and subduction zones were primarily the result of convection currents in the mantle dragging on the crust and supplying fresh, hot magma at mid-ocean ridges. further developments of the theory suggested that some form of ridge push helped supplement convection in order to keep the plates moving, but in the 1990s, calculations indicated that slab pull, the force that a subducted section of plate exerts on the attached crust on the surface, was an order of magnitude stronger than ridge push. as of 1996, slab pull was generally considered the dominant mechanism driving plate tectonics. modern research, however, indicates that the effects of slab pull are mostly negated by resisting forces in the mantle, limiting it to only 2-3 times the effective strength of ridge push forces in most plates, and that mantle convection is probably much too slow for drag between the lithosphere and the asthenosphere to account for the observed motion of the plates. this restores ridge push as one of the dominant factors in plate motion.
ridge push