Sea Floor Spreading Divergent Boundary

Divergent boundaries also form volcanic islands which occur when the plates move apart to produce gaps that molten lava rises to fill.

Sea floor spreading divergent boundary.

On earth magma forms by partial melting of silicate rocks either in the mantle continental or oceanic crust. In this way the rugged volcanic landscape of a mid ocean ridge is created along the plate boundary. As upwelling of magma continues the plates continue to diverge a process known as seafloor spreading. Seafloor spreading occurs at a divergent boundary.

Samples collected from the ocean floor show that the age of oceanic crust increases with distance from the spreading centre important evidence in favour of this process. Seafloor spreading is the usual process at work at divergent plate boundaries leading to the creation of new ocean floor. When the fissure opens pressure is reduced on the super heated mantle material below. Most active divergent plate boundaries occur between oceanic plates and exist as mid oceanic ridges.

Does sea floor spreading occur at a convergent boundary answers no. As two tectonic plates slowly separate molten material rises up from within the mantle to fill the opening. Magma rises up from the mantle and oozes out from the cracks like a long thin undersea volcano. The less dense material rises often forming a mountain or elevated area of the seafloor.

These age data also allow the rate of seafloor spreading to be determined and they show that rates vary from about 0 1 cm 0 04 inch per year to 17 cm 6 7 inches per year. Divergent boundaries in the middle of the oceans cause seafloor spreading. The spreading however is generally not uniform causing linear features perpendicular to the divergent boundaries. As the oceanic plates move apart they produce cracks in the ocean floor.

Seafloor spreading occurs at divergent plate boundaries. Extensional forces stretch the lithosphere and produce a deep fissure. When a divergent boundary occurs beneath oceanic lithosphere the rising convection current below lifts the lithosphere producing a mid ocean ridge. Because of this the youngest sea floor can be found along divergent boundaries such as the mid atlantic ocean ridge.

For example andesitic magmatism associated with the formation of island arcs at convergent plate boundaries or basaltic magmatism at mid ocean ridges during sea floor spreading at divergent plate boundaries. As tectonic plates slowly move away from each other heat from the mantle s convection currents makes the crust more plastic and less dense.