The principal investigator will study the timing of global events such as eustatic changes in sea level, extraterrestrial impact events, deep sea hiatuses, changes in stable isotope compositions of sea water, intervals of rapid faunal turnover in the stratigraphy of the middle Eocene to lower Oligocene (Claibornian to lower Vicksburgian) of the Atlantic and Gulf Coastal Province. A chronostratigraphic framework model based on the Graphic Correlation technique and calibrated to time has been developed by the principal investigator. It will be used to make long distance and regional correlations of rocks, biozones, sequence stratigraphic units, and determine the age of regional and global events, and measure durations and rates. In the interval near the Eocene-Oligocene boundary the stable isotope compositions of three kinds of microfossils (benthic and planktic foraminifers and ostracodes) will be examined to see how curves developed with these data compare to those from the open ocean. This stratigraphic interval will also be studied in detail for magnetopolarity reversals. The predictive value of the chronostratigraphic model is used to indicate stratigraphic intervals where microtektite and other microspherules might be found. These will be sampled and the microspherules studied for mineralogy and chemical composition. This research will provide insight into the role of extraterrestrial impacts on the evolution of life.
