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DRAFT Febmary 25, 1998 • shows a strong relationship to the source lithology of the adjacent upstream debris fan. These observations suggest that the Green River through the eastern Uinta Mountains has been dominated by aggradation during recent geologic time. The depositional settings created by debris fans consist of (1) channel-margin deposits in the backwater above the debris fan, (2) eddy bars in the zone of recirculating flow below the constriction, and (3) expansion gravel bars in the expansion below the zone of recirculating flow. These fan-eddy complexes are the storage location of about 70 percent, by area, of all fine- and coarse-gained alluvium contained within the canyons above the low-water stage. Immediately adjacent meandering reaches contain an order of magnitude more alluvium by area but have no debris fan-created depositional settings. Guensch, G.R., and L C. Schmidt. 1996. Channel Response to High Discharges in 1996, Green River at Ouray and Mineral Bottom. 1996 Annual Progress Report. Department of Geography and Earth Resources, Utah State University, Logan, Utah. 16p. The channel response of the Green River to the 1996 flood was measured in areas considered to contain critical Colorado squawfish nursery habitat. These areas are located at Ouray and Mineral Bottom. Cross sections at each of these study reaches were • surveyed during various flood stages in 1996. Each reach was also topographically mapped. Cross sections surveyed in 1996 were compared with surveys from 1993 and 1994. At Ouray, the 1996 flood created higher elevation sand bars than existed after the 1993 or 1994 floods. Bar building occurs during flood recession. At Mineral Bottom bars do not build nearly as high, relative to the peak flood stage, as they do at Ouray. As a result, less nursery habitat is available at Mineral Bottm than at Ouray. Our data illuminate several characteristics of the Mineral Bottom study reach that may explain its geomorphic behavior. The channel at Mineral Bottom is generally narrower than at Ouray, has a slightly higher gradient, and is more isolated from its historic floodplain due to its high banks. The topographic maps show that bar complexity at Ouray in 1996 was less than in 1994 or 1995 but greater than that following the 1993 flood of slightly less magnitude. Harvey, M.D., and R.A. Mussetter. 1994. Green River Endangered Species Habitat Investigations. Resource Consultants & Engineers, RCE Ref. No. 93-166.02. Ft. Collins, Colorado. 4-1 to 4-4. This investigation of a known Colorado squawfish spawning bar located at the head of Gray Canyon on the Green River tested the researchers proposed physical process-biological response model (PRM) for spawning habitat formation. This model was initially developed from data and analyses conducted about 27 km upstream from the Yampa and Green Rivers confluence in the lower Yampa River Canyon (Harvey et al., • 22