Understanding Earth Systems in the early Paleozoic using high-resolution stratigraphy

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I am proposing a 5-year research program to examine physical, biological, and chemical processes spanning the Ordovician-Silurian boundary. This time interval coincides with one of the three major Phanerozoic glaciations and one of the three largest Phanerozoic extinction events. The early Paleozoic Icehouse, like the current icehouse, had climatic pulses and sea-level cycles driven by the waxing and waning of continental ice sheets initiated in the southern hemisphere. Its initiation under an atmosphere with carbon dioxide level roughly 10 to 15 times higher than the present-day, however, is unique. Continental-scale glaciations under such greenhouse conditions and prior to the development of a major terrestrial biosphere attest to the complex climate dynamics and the susceptibility of the climate system to factors beyond atmospheric composition. The overall goal of this research program is to answer 21st century questions about the ocean-atmosphere-biosphere system during one of the most dynamic intervals in Earth history. Carbonate sedimentary rocks like those well exposed on Anticosti Island are, if ordered and interpreted correctly, represent a storehouse of considerable information to decipher the cause-and-effect relationships within the ocean-atmosphere-biosphere system in the deep geological time. My research program represents an excellent opportunity for students to work on Anticosti Island, a superb geological laboratory, to acquire essential skills in carbonate sedimentology, stratigraphy and paleontology and to meet, as my former students did, the requirements of potential employers in industry, government and academia.