Geoscientists study the physical aspects of the Earth, such as its composition, structure, and processes, to learn about its past, present, and future. In a day in the field, they may use a hammer and chisel to collect rock samples and then use sophisticated radar equipment to search for oil underground. In laboratories, they may use x rays and electron microscopes to determine the chemical and physical composition of rock samples. They also use remote sensing equipment to collect data and advanced geographic information systems (GIS) and modeling software to analyze data. Many geoscientists are involved in the search for and development of natural resources and minerals such as petroleum. Others work in environmental protection and preservation and are involved in projects to clean up and reclaim land. Geoscientists need at least a bachelor’s degree for entry-level positions. A Ph.D. is necessary for most high-level research and college teaching positions. A degree in geosciences is preferred, although degrees in physics, chemistry, biology, mathematics, engineering, or computer science are usually accepted if they include coursework in geology.