[environmental GIS] Acronym for United States Geological Survey. A scientific agency of the U.S. government, part of the Department of the Interior. The U.S. Geological Survey is a fact-finding research agency that monitors, analyzes, and provides scientific understanding about natural resource issues and conditions, the environment, and natural hazards. The U.S. Geological Survey is the primary civilian mapping agency in the United States. It produces digital and paper map products; aerial photography; and remotely sensed data on land cover, hydrology, geology, biology, and geography.