The mantle makes up the bulk of Earth, extending from near the surface to the edge of the core 2900 km down. It constitutes 84% of Earth’s volume and has roughly 6 times the mass of Mars! Despite its impressive bulk, the mantle is almost everywhere covered by several km of crust. As a result we don’t have a lot of pieces of it that we can look at, hold or study. Those we have (e.g. xenoliths ...[Read More]