Present-day deformation across the basin and range province, western United States

The distribution of deformation within the Basin and Range province was det ermined from 1992, 1996, and 1998 surveys of a dense, 800-kilometer-apertur e, Global Positioning System network. Internal deformation generally follow s the pattern of Holocene fault distribution and is concentrated near the w estern extremity of the province, with Lesser amounts focused near the east ern boundary. Little net deformation occurs across the central 500 kilomete rs of the network in western Utah and eastern Nevada. Concentration of defo rmation adjacent to the rigid Sierra Nevada block indicates that external p late-driving forces play an important role in driving deformation, modulati ng the extensional stress field generated by internal buoyancy forces that are due to Lateral density gradients and topography near the province bound aries.