What force causes the seafloor spreading?
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.
What causes seafloor spreading and continental drift?
Seafloor spreading and other tectonic activity processes are the result of mantle convection. Mantle convection is the slow, churning motion of Earth’s mantle. As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense.
What is the primary force that causes the seafloor to spread and continents to drift 17 letters?
Convection Currents
Convection Currents Convection forms into currents that drive the tectonic plates either together or apart. The seafloor spreads along diverging boundaries, but it also contracts along the converging boundaries as seafloor is pushed below the surface by two plates in collision with each other.
How is convection related to the spreading of the seafloor?
Mantle convection is the slow, churning motion of Earth’s mantle. Convection currents carry heat from the lower mantle and core to the lithosphere. Convection currents also “recycle” lithospheric materials back to the mantle. Seafloor spreading occurs at divergent plate boundaries.
How does seafloor spreading and subduction affect the Earth?
Seafloor spreading creates new crust. Subduction destroys old crust. The two forces roughly balance each other, so the shape and diameter of the Earth remain constant. Earth’s newest crust is created at sites of seafloor spreading—red sites on this map.
How does the surface of the Earth Move?
The surface of the Earth is made of interlocking tectonic plates. The tectonic plates are always moving in relation to each other. When two plates pull away from each other, the seafloor spreads along the boundary of the two plates. At the same time, it contracts in another area. The Continental Drift Theory.
How did scientists discover the spreading of the ocean floor?
The magnetism of mid-ocean ridges helped scientists first identify the process of seafloor spreading in the early 20th century. Basalt, the once- molten rock that makes up most new oceanic crust, is a fairly magnetic substance, and scientists began using magnetometer s to measure the magnetism of the ocean floor in the 1950s.