Admin What is seafloor spreading called?
The phenomenon is known today as plate tectonics. In locations where two plates move apart, at mid-ocean ridges, new seafloor is continually formed during seafloor spreading.
How seafloor spreading and the evidence supports this theory?
Abundant evidence supports the major contentions of the seafloor-spreading theory. Magnetic surveys conducted near the mid-ocean ridge showed elongated patterns of normal and reversed polarity of the ocean floor in bands paralleling the rift and symmetrically distributed as mirror images on either side of it.
What are the four steps of seafloor spreading?
Terms in this set (7)
- Magma comes out of the rift valley.
- Magma cools to rock and hardens.
- Rock is pushed away as new rock is formed at MOR.
- Oceanic crust and continental crust meet at the trench.
- Oceanic crust bends down under the continental crust.
- Gravity pulls rock towards mantle.
- Rock melts to mantle.
Where does seafloor spreading happen?
mid-ocean ridges
Seafloor spreading occurs along mid-ocean ridges—large mountain ranges rising from the ocean floor. The Mid-Atlantic Ridge, for instance, separates the North American plate from the Eurasian plate, and the South American plate from the African plate.
What is the difference between a slowly spreading and rapidly spreading seafloor?
Seafloor spreading is not consistent at all mid-ocean ridges. Slowly spreading ridges are the sites of tall, narrow underwater cliff s and mountains. Rapidly spreading ridges have a much more gentle slopes. The Mid-Atlantic Ridge, for instance, is a slow spreading center.
What happens to the seafloor when a continent is severed?
Seafloor spreading can stop during the process, but if it continues to the point that the continent is completely severed, then a new ocean basin is created.
Who proposed the theory of seafloor spreading?
Continental Drift and Seafloor Spreading. This seafloor spreading hypothesis had been proposed a few years earlier by Harry Hess, a petrologist at Princeton University, and Robert Dietz, an oceanographer in the US Coast and Geodetic Survey (the federal department that made maps of the oceans and US coastlines).
What is the difference between sea floor spreading and mantle convection?
Seafloor spreading is a geologic process in which tectonic plates—large slabs of Earth’s lithosphere—split apart from each other. Seafloor spreading and other tectonic activity processes are the result of mantle convection. Mantle convection is the slow, churning motion of Earth’s mantle.