= Geologist
A <geologist> studies Earth's materials, structures and history through rocks, field relationships and physical or chemical <measurements>. A rock's mineral composition, texture and position relative to other units constrain the processes that formed and later altered it.
For example, a cross-cutting intrusion is younger than the rocks it cuts, while isotopic <measurements> can supply numerical age information under specified assumptions. Field context and laboratory data answer complementary questions.
Back to article page
