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10 <br />• to be understood. Dec~ils of isotope principles at,d me4~todology have been outlined in <br />Faure (19$6), whereas Pratt ((985) provides an overview of application of <br />paleocnvironmental interpretations to Middle and Upper Cretaceous cazbon and oxygen <br />isotopic data. <br />Light stable isotope (isotopic oxygen, isotopic carbon) and geothemical (% <br />CaC03, Corg) results of this study are presented in Figs. 7-R, and in the Appendix. All <br />figures show the expanded Wagon Mound, New Mexico section on the left as a <br />sUatigraphic guide to general lithology. Lines of correlation shown in the figures do not <br />cross lithological isochrons, inasmuch as the values derived from shale bed Z.S, for <br />example, are only correlated with [he identical bed within the other sections. Correlative <br />data paints at Wolcott and Badito were tied into the lower (shale) samples at Wagon <br />Mound, under the assumption that during the initiation of shale deposition, all sections <br />within the study area were receiving- terrigenous sediments, and are therefore <br />isochronous. The Pycnodonte biostrome (base of LS 5) serves as the datum line in all <br />figures. Chemostra[igraphic analyses were not undertaken for the Canon City and <br />Trinidad sections, but are in preparation with the U.S. Geological Survey. isotopic <br />organic carbon %e and elemental suite analyses are also being developed for all five <br />localities. <br />The most s[taightforward geothemical data are those of volumetric percent of <br />• calcium carbonate. As would be expected, the % CaCG3 values of the shale interbeds is <br />considerably lower than the limestones, as indicated in the table below: <br />TABLE 1 <br />Average Percentage CaC03 <br />Locality Shale Limestone <br />Wolcott, Colorado ................................................. 59.6% 84.5% <br />Badito, Colorado ................................................... 64.5% 91.0% <br />Wagon Mound, New Mexico ................................ 52.3% 79.2% <br />• [limestone beds from the RGPCC drill cores are closest to the Badito section values.] <br />Within the "western facies belt", the Wolcott section may have been directly affected by <br />fine-grained clastic sediments shed to [he southeast by the large Frontier Delta complex <br />of central Wyoming (McGookey e! al., 1972). The Badito section clearly had the highest <br />calcite percentages, with one sample (from bed LS 7) yielding a % CaCO~ value of <br />98.8%. These values aze likely reflected in the FoR Hays Member outcrops immediately <br />• zuoo <br />