Quaternary history of some southern and central Rocky Mountain basins

This chapter summarizes the current state of late Cenozoic stratigraphic knowledge in some Rocky Mountain basins (here defined as the structurally low portions of major drainage basins) that have been studied in detail since Scott’s (1965) summary on the nonglacial history of the southern and middle Rocky Mountains. The Quaternary history of few of these basins has been studied as intensively as that of the surrounding mountain ranges, despite the wealth of fluvial and other types of deposits present in the basins and the potential for dating them. The areas discussed here include the Bighorn Basin in Wyoming and Montana, the Laramie Basin and part of the Sweetwater River Basin in Wyoming, the Yampa River Basin in Colorado, and the Uinta Basin in Utah (Fig. 1). Small parts of the Great Plains and Colorado Plateau physiographic provinces are included in this discussion. Correlations of deposits within and among some of the areas can now be made more confidently than in 1965 because of detailed mapping and the discovery of many more localities with dated volcanic ashes.