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PALEONTOLOGICAL ASSt.SSMFNT <br />A paleontological assessment of the project area was made to ascertain the potential of <br />geologic units within the project area boundary to yield vertebrate fossils, including a review- of <br />pertinent scientific literature and maps and an on -site reconnaissance of accessible outcrop <br />exposures within the project area. These activities were conducted by Carl Conner (GRI <br />Archeologist). Joshua A. Smith (GRI Paleontologist), and Lucas Pointkowski (GRI <br />Archeologist). The fallowing summarizes our findings. <br />The Mesaverde Formation (also considered the Mesaverde Group) occurs within the <br />project area (Tweto. 1979) and is a collection of geologic units (formations and members) <br />recognized throughout its extent as assorted deltaic deposits formed along the <br />westerWnorthwestern shoreline of the transgressing and regressing Western Interior Seaway <br />during Late Cretaceous time. The Mesaverde Forniation contains an extensive variety of <br />lithologies including terrestrial sandstones. mudstones, and coals, and also nearshore marine <br />sandstones in the lower formations and members where the Mesaverde intertounges with <br />marine deposits of the Nlancos Shale (Yount! 1955, Hettinger and Kirschbaum 2002; <br />Kirschbaum and Hettinger 2000. <br />Various geologic: designations and nomenclature have historically been used for the <br />units in the Mesaverde due to the mane depositional sequences preserved over several episodes <br />of Western Interior Seaway shoreline advance and retreat during the late Cretaceous <br />(Papadopulos. 2008); in the project area, the Rollins Sandstone Member is the lowest <br />stratigraphic unit in the Mesaverde Formation, and the Ohio Creek Member is the highest <br />stratigraphic unit (Hettinger ct al. 2002). Kirschbaum and Hettinger (2000 consider the <br />Rollins Sandstone a member of the Late Campanian Mount Garfield Formation (within the <br />larger Mesaverde Group), where it is stratigraphically the highest of a series of three nearshore <br />marine sandstones: these authors. along with others (Collins. 1976; Brownfield et al.. 1999), <br />acknowledge the correlation of this unit with the Trout Creek Member (Fenneman and Gale. <br />1909) of the lies Formation (Mesaverde Group) in the Grand Central Hogback area of Garfield <br />County, Colorado (Madden. 1989). Above the Rollins Formation in the project area are two <br />coal - bearing; units, the Bowie Shale and Paonia Shale (in ascending order) of the <br />Cameo - Wheeler Coal lone. and they are overlain by a thick (300+ feet) sandstone unit called <br />the "Barren Member': these latter three units are mapped as members of the Williams Fork <br />Formation (Mesaverde Group) (Papadopulos 2008). <br />Fossils known from the Mesaverde Group include the remains of a wide variety of early <br />mammals, including species of multituberculates, primitive marsupials. and placentals. and <br />teeth from unknown therians which can not be classified as placental or marsupial based on <br />dental anatomy. Other fossils include: fishes including ehondrichthians and osteichthians; <br />amphibians. reptiles including turtles. lizards. snakes, birds and crocodilians. Dinosaurs from <br />18 <br />