Sea Floor Spreading Centers

Mantle convection is the slow churning motion of earth s mantle.

Sea floor spreading centers.

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. 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. The neovolcanic zone is at the very axis. Spreading centres are divided into several geologic zones.

There is more information here than you need for this exercise. Spreading centers end in transform faults or in overlapping spreading center offsets. When the magma reaches water at the ocean floor most spreading centers are in the ocean it cools and hardens and becomes new. Where are most seafloor spreading centers located.

Seafloor spreading theory that oceanic crust forms along submarine mountain zones and spreads out laterally away from them. The portion that links to the two ridges is the transform fault see also the above diagram and. This is thought due to temperature gradients in the asthenosphere from mantle plumes near the spreading center. Here the plate motion opens a gap between the plates and magma from the mantle rises up through it.

Seafloor spreading occurs at spreading centers distributed along the crests of mid ocean ridges. Seafloor spreading and other tectonic activity processes are the result of mantle convection. The life cycle of the seafloor lesson plan by ashlee henig and stephen halpern. 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.

Adjacent to the neovolcanic zone is one marked by fissures in the seafloor. Spreading center definition a linear zone in the sea floor along which magma rises and from which adjacent crustal plates are moving apart. This is a schematic diagram of a spreading ridge. Spreading centers occur at the boundary between two plates that are moving apart called divergent plate boundaries.

Beginning with early evidence of continental drift such as the fit of landmasses and. 2013 12 18 19 39 33 2013 12 18 19 39 33. It is the mid ocean ridges. Convection currents carry heat from the lower mantle and core to the lithosphere.