GEOCHEMICAL AND PHYSICAL DETERMINATION OF DIAGNOSTIC K-PG BOUNDARY FEATURES USING NITON XRF T3GOLDD+ FOR CORRELATION OF SELECTED LOCATIONS IN WYOMING AND COLORADO

The boundary between the Cretaceous and Paleogene is a very thin stratigraphic sequence interval documented in localities around the world that records a catastrophic meteorite impact event that occurred about 66 million years ago. Its geochemical components have been analyzed using various methods in the laboratory, over the years, for the western United States. Locations were selected in Colorado and Wyoming to use a hand held Niton XRF T3 GOLDD+ analyzer tool to determine the geochemical signature in the field. For comparison, samples analyzed in the field were returned to the laboratory and analyzed again using the Niton XRF T3 GOLDD+ analyzer. These samples were then also re- examined in the laboratory for features such as shocked quartz, glass spherules, carbonaceous material, and clasts often associated with the boundary layers. A preliminary characterization checklist was developed for identification, correlation, and mapping the boundary in the field. The portable equipment provides a means for non-destructive analyses so that the same sample can be tested in both the field and the laboratory for its constituent elemental components, as well as its sedimentary-stratigraphic components. This represents a suite of analytical applications that is important for determination and correlation of field variability. Detailed field mapping is enabled over the extent of the boundary with the opportunity to confirm field results in the laboratory.