Geologists are scientists who specialize in the formation and composition of rocks and soil. They work to understand the health of soils, the movement and formation of earth, as well as how landslides, earthquakes, waterways, and volcanic eruptions occur. 

Geologist is an umbrella term, as most of these scientists become specialized in one specific earth process. For instance, geologists who study volcanoes are known as Volcanologists, while those who study earthquakes are known as Seismologists. 

Many geologists work to locate water, oil, gas, metals, or precious gems for the mining and energy industries. Roughly 25% of geologists are said to work in the extraction of oil and gas. Many others work on engineering projects, such as helping to build wells, develop water projects, determine soil composition, and work alongside botanists and wildlife biologists to access the health of an ecosystem.