Se Floor Spreading

The oceanic crust is composed of rocks that move away from the ridge as new crust is being formed.

Se floor spreading.

The rate at which new oceanic lithosphere is added to each tectonic plate on either side of a mid ocean ridge is the spreading half rate and is equal to half of the spreading rate. As north america and south america moved away from europe and africa the resulting crack was filled by mantle material which cooled and formed new lithosphere. Seafloor spreading occurs along mid ocean ridges large mountain ranges rising from the ocean floor. That is it explains why the age thickness and density of the oceanic crust increases with distance from the mid oceanic ridge.

The process of sea floor spreading created the lithosphere under the atlantic ocean. The following features are shown at example depths to scale though each feature has a considerable range at which it may occur. Spreading rates determine if the ridge is fast intermediate or slow. Molten mantle materials continually rise to fill the cracks formed as.

The continents bordering the atlantic ocean for example are believed to be moving away from the mid atlantic ridge at a rate of 1 2 cm 0 4 0 8 inch per year thus increasing. The formation of the new crust is due to the rising of the molten material magma from the mantle by convection current. Continental shelf 300 feet continental slope 300 10 000 feet abyssal plain 10 000 feet abyssal hill 3 000 feet up from the abyssal plain seamount 6 000 feet. The mid ocean ridge is the region where new oceanic crust is created.

The process continues today. Sea floor spreading the theory that the ocean floor is created at the spreading accretionary plate margins within the ocean basins. Igneous rocks rise along conduits from the mantle giving rise to volcanic activity in a narrow band along the mid ocean ridges as these cool the basaltic lavas and dykes form the upper part of the oceanic crust and the underlying magma chamber solidifies to. The process of sea floor spreading.

The theory of sea floor spreading states that new oceanic crust is being formed continuously at mid oceanic ridges while the older rocks move away from the ridge. Spreading rate is the rate at which an ocean basin widens due to seafloor spreading. This graphic shows several ocean floor features on a scale from 0 35 000 feet below sea level.