Spreading of seafloor occurs at the mid-ocean rifts, where there is a continuous flow of material rising from the mantle. There is not a unanimously accepted theory as to the cause of the rifting that is taking place. Once the rifting and mantle material inflow has started, however, the conduit is in place. The thinness of the crust at the rift makes it easier for the material to rise, and as it rises it becomes molten and emplaces itself to form new oceanic crust when it solidifies. The rising material is part of a convection current in the Earth's mantle. At the opposite end of the current are subduction zones, where oceanic crust sinks back into the mantle and melts, causing surface features as composite volcanoes. With this cycle of creation and destruction, the total area of seafloor remains relatively stable, but continents change in relative position to each other. These changes do not occur rapidly. The average speed of crustal plate movement is less than the average rate of fingernail growth.
Subduction and sea floor spreading are both a result of the movement of the tectonic plates.
Plate Tectonics
Together, they change the size and shape of the oceans.
The sea floor is being constinty made. As the new sea floor pushes the old sea floor farther away, the old sea floor hits and another plate then the denser plate subducts under into he matle
Plate Tectonics
convection.
Rising materials causes rifting; sinking material causes subduction.
Subduction and sea floor spreading are both a result of the movement of the tectonic plates.Plate Tectonics
Tectonic.
The process of an ocean plate meeting with land plate and pushing under is called subduction. This process causes serious mountain building and seismic activity.
heat and pressure of the 2 plates pushing against each other.
Rising materials causes rifting; sinking material causes subduction.
no magma riseing thur gaps in plate causes them to move called seafloor spread
Subduction and sea floor spreading are both a result of the movement of the tectonic plates.Plate Tectonics
Subduction and sea floor spreading are both a result of the movement of the tectonic plates.Plate Tectonics
Convective flows of molten rock beneath the Earth's crust causes tectonic plates to spread apart in one area and to sink or be subducted beneath another plate at the opposite edge of the plate.
Seafloor spreading
Actually it formed where two plates hit each other and one was subducted.. This subduction, or moving under, causes trenches to form. This in fact is how the marianas trench was formed.
rising molten magma
Tectonic.
Seafloor spreading occurs along mid-ocean ridges. Mid-ocean ridges are large mountain ranges on the ocean floor. The shifting in the rock causes the seafloor to spread and allows magma to bubble and form more mountains on the ocean floor.
The process of an ocean plate meeting with land plate and pushing under is called subduction. This process causes serious mountain building and seismic activity.
Geothermal Drift.