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SENT BY~FSP&T, LLC, 02 ;11-20- <br />1~ <br />• SUMMARY & CONCLUSIONS <br />The Foregoing discussion provides a comprehensive and up-to-date summary of <br />the Fort Hays Limestone, it's paleoecology, depositional settings, and paleoenvirotunents. <br />The Fort Hays Limestone (Lower Coniacian; -89.0 to 88.0 Ma BP) was deposited over a <br />broad area of [he central Western Interior of [he United States during the maximum <br />transgression of the Cretaceous Niobrara seaway. Massive limestones and chalkstones of <br />the Fort Hays Member aze well exposed over much of eastern Colorado, western Kansas, <br />central Nebraska, and northeastern New Mexico. Limestones within the Fort Hays Mbr <br />grade into calcareous shale and then to mudstone towards the west, and grade into chalk <br />to the east. <br />Shale interbeds are thickest to the west, owing to the closet proximity to the <br />sediment supply azea of the proto-Rocky Mountains. Similar lithologic bedding patterns' <br />are observed in'the age-equivalent Atco Member (Austin Chalk Formation) in the Gulf <br />Coast region of western Texas. Observed variations in cazbpn, sulfur, ammonium nitrate <br />compounds, and silicate/alumina ratios of both Fort Hays Member limestones and <br />subordinate shale interbeds indicate that these deposits are ideally suited for use in the <br />manufacturing of Portland cetnent. This situation exists today due to the depositional <br />nature of the Fort Hays Member in the geological past, specifically: <br />• I.) distance from the western paleashoreline /muddy sediment source <br />2.) southward-flowing geostrophic / longshore currents (trapping suspended mud-sized <br />sediments farther to the west than the pueblo area), and <br />3.) position of the RGPCC properties on the active Tiaras-Continental Arch. <br />• 2003 <br />