Sea Floor Spreading Centers

Seafloor spreading theory that oceanic crust forms along submarine mountain zones and spreads out laterally away from them.

Sea floor spreading centers.

Spreading centers end in transform faults or in overlapping spreading center offsets. 2013 12 18 19 39 33 2013 12 18 19 39 33. This 9 block day lesson plan leads students through the discovery of plate tectonics in much the same way scientists learned about it in the 1960 s. This idea played a pivotal role in the development of the theory of plate tectonics which revolutionized geologic thought during the last quarter of the 20th century.

The neovolcanic zone is at the very axis. Convection currents also recycle lithospheric materials back to the mantle. Beginning with early evidence of continental drift such as the fit of landmasses and. Where are most seafloor spreading centers located.

Here the plate motion opens a gap between the plates and magma from the mantle rises up through it. Seafloor spreading takes place at the boundaries of divergent plates whereby as the divergent tectonic plates move away from each other hot convectional currents from the mantle cause the lithosphere the ocean crust to become less dense ductile and brittle and therefore rise above the surrounding crust to form a submarine mountain. The portion that links to the two ridges is the transform fault see also the above diagram and. This is a schematic diagram of a spreading ridge.

There is more information here than you need for this exercise. Spreading centres are divided into several geologic zones. Spreading center definition a linear zone in the sea floor along which magma rises and from which adjacent crustal plates are moving apart. When the magma reaches water at the ocean floor most spreading centers are in the ocean it cools and hardens and becomes new.

It is the mid ocean ridges. It is 1 to 2 km 0 6 to 1 2 miles wide and is the site of recent and active volcanism and of the hydrothermal vents it is marked by chains of small volcanoes or volcanic ridges. This is thought due to temperature gradients in the asthenosphere from mantle plumes near the spreading center. Convection currents carry heat from the lower mantle and core to the lithosphere.

Spreading centers occur at the boundary between two plates that are moving apart called divergent plate boundaries. The key thing to focus on is the geometry of how the spreading center is offset by a linear feature that is roughly perpendicular to the spreading center. Seafloor spreading occurs at spreading centers distributed along the crests of mid ocean ridges. Adjacent to the neovolcanic zone is one marked by fissures in the seafloor.