The term for a scientist who studies rocks is "petrologist." Petrologists typically focus on the origin, composition, and structure of rocks, providing insights into geological processes and Earth's history. They analyze samples from various locations, studying igneous, sedimentary, and metamorphic rocks to understand their formation and transformation over time. This knowledge is essential for natural resource exploration, environmental assessment, and understanding natural hazards, such as earthquakes or volcanic eruptions. Petrologists often work in conjunction with other geoscientists, contributing to research in fields such as mineralogy, geochemistry, and geology, to develop comprehensive models of the Earth's crust.