DETERMINING CONTROLS ON SILICIFICATION IN MISSISSIPPIAN FOSSILS OF THE ROCKY MOUNTAIN REGION

Taphonomic processes of fossilization can seriously undermine the fidelity of paleoecological analyses. Silicification creates ideal samples for acidification and taxonomic description, but may degrade the integrity of community analysis. Many variables including original mineralogy and shell microstructure, depositional environment, and diagenetic cements can affect the particulars of silicification. Selective silicification occurs in the faunas of the western Rocky Mountain region which defies established models of silicification. The Arco Hills Formation has a range of phyla (bryrozoans, cnidarians, brachiopods, molluscs, arthropods, and echinoderms) with inconsistent degrees of silicification. Understanding the influence of these variables is essential to lucid paleoecological interpretations.