Question

What kind of rocks would you expect to see on Mars? What evidence supports your response?

Answer 1

Based on the composition of the martian meteorites and the presence of plains and mountains that look like features produced by basaltic volcanism on Earth, geologists expected to find primarily basalts on Mars.

Answer 2

Mars' surface is largely covered with basalt, a volcanic rock covering much of Earth's surface as well. Earth has large amounts of granite in its crust, which Mars appears to lack.