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47 <br /> 3.0 Inventory Results <br /> 3. 1 Geologic/Paleontological Resources <br /> As a whole, exposures of strata in Dowe Flats are not very good, <br /> thus limiting the possibility of discovering fossils. Some <br /> strata at the Codell sandstone-Fort Hays Limestone boundary is <br /> exposed along the St. Vrain Supply Canal . The strata has been <br /> temporarily exposed by maintenance work along the canal . <br /> Invertebrate burrows were seen in the Codell and nothing else. <br /> A ridge of Fort Hays Limestone bisects Dowe Flats through the <br /> middle of the eastern half of Section 9 south to Section 16. <br /> Very few fossils were seen, these being the casts of inoceramid <br /> clams and possible invertebrate burrows. These fossils are not <br /> scientifically important and were not collected. <br /> The oldest strata in Dowe Flats are the Dakota Group. These <br /> strata are steeply dipping and form the east, north and west rims <br /> of the Flats . The group consists of about 330 feet of sandstone <br /> and shales. It is subdivided into the Lytle and South Platte <br /> formations which record the beginnings of the seaway spreading <br /> west across Colorado during the Cretaceous. <br /> Fossils in the Dakota Group are known from near Golden and <br /> Boulder (Carpenter notes) , and includes dinosaur footprints and <br /> trace fossils in the basal portion of the South Platte Formation. <br /> An undescribed skeleton of a large fish is also known from <br /> southeastern Colorado (Denver Museum of Natural History <br /> collections) . <br /> Conformably overlying the Dakota Group is the Graneros Shale. <br /> This dark shale, about 160 feet thick, records deepening of the <br /> marine waters during the Late Cretaceous. This shale is poorly <br /> exposed in Dowe Flats because it erodes quickly and is soon <br /> overgrown by vegetation. Invertebrate fossils have been reported <br /> from elsewhere by Kauffman (1977) and include various trace <br /> fossils, clams, oysters, and ammonites. Vertebrate fossils <br />