There is no basalt under the continent s granite.
Why didnt granite sink down into eaths mantel.
They separate and sink down into the mantle leaving behind silica rich magma that has the right composition to form granite.
It reaches the location where warm mantle material rises and the mantle convection cell is complete.
It also extracts the so called incompatible elements which don t fit into mantle minerals and move into the liquid melt.
The mantle is about 2 900 kilometers 1 802 miles thick and makes up a whopping 84 of earth s total volume.
Convection in the mantle is the same as convection in a pot of water on a.
The earth has gas.
The mantle is the mostly solid bulk of earth s interior.
The mantle extends down to 2 890 km into the earth s surface temperatures that range from 500 to 900 degrees celsius in the upper portion to over 4 000 degrees celsius near the core boundary.
Unexpectedly helium hydrogen nitrogen and even carbon dioxide from microbes were found all along the borehole.
It eventually becomes cool and dense enough to sink back down into the mantle.
The mantle lies between earth s dense super heated core and its thin outer layer the crust.