The Seafloor Spreading

Convection currents within the mantle take the continents on a conveyor belt ride of oceanic crust that over millions of years takes them around the planet s surface.

The seafloor spreading.

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 motivating force for seafloor spreading ridges is tectonic plate slab pull at subduction zones rather than magma pressure although there is typically significant magma activity at spreading ridges. The process begins when the crust is heated from beneath by upwelling in the mantle sometimes called a mantle plume. Seafloor spreading and other tectonic activity processes are the result of mantle convection.

Mantle convection is the slow churn ing motion of earth s mantle. In sea floor spreading new crust is added at a. Seafloor spreading is a geologic process in which tectonic plate s large slabs of earth s lithosphere split apart from each other. Seafloor spreading is a constant geologic phenomenon and a primary driver of continental drift.

The seafloor s permanent magnetic signatures showed that new ocean crust was created at the ridge crests and then spread outward in both directions. Seafloor spreading theory that oceanic crust forms along submarine mountain zones known collectively as the mid ocean ridge system and spreads out laterally away from them. Seafloor spreading is the mechanism for wegener s drifting continents. What happens to old oceanic crust as new molten material rises from the mantle.

This creates a three armed rift called a triple junction usually with each rift at a 120 angle to the rest. Seafloor spreading helps explain continental drift in the theory of plate tectonics. The breakup of pangaea by seafloor spreading is seen in this animation. The mid ocean ridge is where the seafloor spreading occurs in which tectonic plates large slabs of earth s lithosphere split apart from each other.

The new material splits apart the old material and pushes it outward from the ridge. In this lesson you will learn about this important. Seafloor spreading is a part of plate tectonics. Seafloor spreading is a geologic process where there is a gradual addition of new oceanic crust in the ocean floor through a volcanic activity while moving the older rocks away from the mid oceanic ridge.

Subduction takes place at. Its discovery provided a mechanism for continental drift that alfred wegener could not explain.