TRACE ELEMENT GEOCHEMICAL VARIATIONS: FOSSIL BIOAPATITE VS. ARAGONITE

My research has primarily been investigating the Rare Earth Elements (REE) and other trace elements (TE) geochemistry and stratigraphy of the deposits of Florida’s modern and ancient coastlines. Recently, I have been granted access to the collections at the University of Florida (UF) museum. This complements the field collections I have done thus far and provides further stratigraphic context for my research into Pleistocene and Miocene deposits of Florida. Stratigraphic variations in REE in two distinct Carbonate paleoenvironments were explored. Florida Pleistocene vertebrate and invertebrate fossils of the Anastasia and the Fort Thompson Formations. This research is the basis for establishing an extensive REE data library for the historically significant fossil collections. A preserved REE signatures pattern in the stabilized material closely reflects the original diagenetic waters during the fossilization process, therefore giving a proxy to ancient ocean geochemistry. Samples were analyzed for Rare Earth Elements (REE) and other trace elements (TE) using the Inductively Coupled Plasma Mass Spectrometer (ICP-MS) at the analytical labs at UF. Invertebrate material (Aragonite) were analyzed and then compared to the REE signatures of the fossil vertebrate material to determine the extent of diagenesis in the ancient samples of both Vertebrates (bioapatite) and invertebrates (calcite). In addition I conducted research (based on my previous crystallographic studies of bioapatite in the Pierre Shale) using X-Ray diffraction (XRD) to take a further look at the fossilization of the bioapatite and calcite. This data library potentially can be used for stratigraphic correlation, interpretation of ancient and modern environments and fossil provenience. In addition the resultant database can be used for a baseline to monitor changing conditions in the modern reef tract systems of Florida.