The Mid-Atlantic Ridge, for instance, separates the North American plate from the Eurasian plate, and the South American plate from the African plate. Mid-Ocean Ridges Seafloor spreading occurs along mid-ocean ridges-large mountain ranges rising from the ocean floor. This rock ( basalt) becomes a new part of Earth’s crust. This bubbled-up magma is cooled by frigid seawater to form igneous rock. Hot magma fueled by mantle convection bubbles up to fill these fractures and spills onto the crust. The less-dense material rises, often forming a mountain or elevated area of the seafloor. As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense. Seafloor spreading occurs at divergent plate boundaries. Convection currents also “recycle” lithospheric materials back to the mantle.
Convection currents carry heat from the lower mantle and core to the lithosphere. Mantle convection is the slow, churning motion of Earth’s mantle. Seafloor spreading and other tectonic activity processes are the result of mantle convection. Seafloor spreading is a geologic process in which tectonic plates-large slabs of Earth's lithosphere-split apart from each other.
0 kommentar(er)
