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Mesaverde contains a greater number of coal beds, indicating that the paludal (marshy) <br />environment was considerably more extensive during deposition of the latter. Fresh water and <br />marine fossils have been found in this formation (Fisher et al. 1959). Dinosaur bones, dinosaur <br />tracks, and gastroliths have been reported from coal mines near the study area. <br />Within the general area. the formation outcrops on the faces of the mesas overlooking <br />the North Fork of the Gunnison. Outcrops tend to weather as tan to brown sandstones with <br />interspersed coal beds. Since vertebrate fossils have been recovered from the coal beds in the <br />region, the potential for the occurrence of vertebrate fossils in this formation is considered <br />gam• <br />Upper Mesaverde ( Barren Member) <br />The formation exposed in the study area is the upper Mesaverde. It consists of buff <br />and grey medium and coarse - grained sandstone (cliff - forming) and grey to greenish -grey shale. <br />Local thickness varies from 375 to 1400 feet (Cashion 1973). Contact with the underlying <br />lower Mesaverde Formation is conformable and visually sharp, and this Late Cretaceous <br />formation is largely undated (Berman ct al. 1980). Mostly continental in formation, the upper <br />Mesaverde represents the last deposits related to the dominantly fluvial homogeneous <br />environment of the Late Cretaceous inland seas. <br />Several factors contribute to the potential of discovering vertebrate fossils in any unit. <br />including previously known occurrences and accessibility of exposures in the field. The <br />"Barren Member- is the only unit of the Nesaverde Formation exposed at the surface within <br />the project area boundary. and its surface expression as small, high. rounded. intermittent <br />outcrops nestled deeply into thickly vegetated, steep hillsides greatly limited access to any <br />outcrops. Due to the lack of previously recorded fossil findings in sediments that make up this <br />formation and the rugged nature of the exposures, the potential for finding fossils in the upper <br />Mesaverde member within the study area was considered low. <br />The study area is covered in a blanket of soil and vegetation, few exposures of this <br />formation occur and consist mainly of ledge faces. As expected no fossils were encountered <br />during the reconnaissance of the surface exposed outcrops. <br />MANAGEItEVT RECOMMENDATIONS <br />The eligibility determination and consultation process is guided by Section 106 of the <br />NAPA (36 CFR 60. 63, and 800). Inventory to identify. evaluate. and mitigate potential effects <br />to cultural resources affected by an undertaking is the first step in the Section 106 process. <br />Federal actions cannot be authorized until the Section 106 process is completed (36 CFR <br />800.3). Final determinations of National Register eligibility and effect should be sought from <br />the controlling federal agency. The actual adverse effects due to subsidence can not be <br />determined as part of this study. <br />21 <br />