Question #69877
1 Answer
Convection currents are caused by cooled solid-lava-like rock sinking down, with the hotter solid-lava-like rock rising to replace that sinking rock and then getting cooled down by the crust above to repeat the process.
Explanation:
In the mantle of the earth, rocks that are kind of solid and kind of liquid is the main material. The rocks at the top of the mantle get cooled down by the tectonic plates above, which are cooler than the mantle. The cooled down rocks sink because they are more dense, so the rocks below rise up to replace the sinking rocks.
Those rocks that sink will sink down far enough to be able to be warmed up the core, which is much warmer than the mantle. At the top, the rocks that rose up eventually cool down enough to sink and the warmed up rocks are able to rise up and replace the cooled rocks. And the process happens over and over, forming the phenomenon known as convection currents.
