Uplift of the Sierra Nevada, California

575 Topography is a fi rst-order indicator of geology, from features as local and simple as resistant strata making ledges, to as regional and complex as how continental-scale mountain ranges are supported by thick crust. Understanding the character and evolution of topography is fundamental to understanding a region’s tectonic evolution. Variations in topography through time have profound implications for processes as obvious as erosion and sedimentation and as diverse as global climate and the formation of mineral deposits. The interplay between topography and tectonics is exemplifi ed by the evolution of topography of the Sierra Nevada and Great Basin (United States), and by geologists’ interpretation of that evolution. The formation of the Sierra Nevada and its relationship to the adjacent Great Basin have been major geologic questions since the 1800’s (LeConte, 1886). From the study of Eocene gold-bearing paleoriver deposits in the Sierra Nevada, Lindgren (1911) concluded that the Eocene mountain range had similar relief but was slightly lower than the modern range. He also inferred a drainage divide roughly coincident with the modern divide, but many geologists subsequently recognized that the paleorivers drained from at least as far east as