Biostratigraphic Investigations: Refining the Geologic Time Scale to Calibrate the Past and Predict Climate Change and Mass Extinction Effects

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Today, the world is affected by critical issues such as climate change, species extinction, and changes to where plants and animals thrive because rising ocean levels and temperatures affect where organisms can live. My research on the Permian System (299 – 252 million years ago) aims to illuminate what may well be the best ancient time interval to show how these issues affected life on the planet in the past. Deep-time studies do not match resolution of near-time studies, but these events have run their full course and provide examples of how natural systems adapted as climate changed. The Permian records the Earth's penultimate ice age and its largest mass extinction. My research on the end-Permian mass extinction has contributed to the emerging consensus that it resulted from climate change, triggered by a massive release of gases from a volcanic region called the Siberian Traps. The impact of climate change is evident in both marine and land-based environments, but the relative timing is not resolved. ******As a paleontologist, I set both the international context and serve as the time-keeper to determine what happened and when. I do this through my study of microfossils called conodonts that are common in most rock types throughout the Permian. Evolution allows us to use them as clocks to calibrate deep time. Small changes in their structure and composition allow us to identify and correlate specific intervals of time around the world (biostratigraphy) and contribute to the calibration of the Geologic Time Scale – one of the fundamental tools of our discipline. My research team is multidisciplinary, including geochronologists, geochemists, and other paleontologists in academic institutions around the world. My graduate and undergraduate students, and post-doctoral scholars, are given the opportunity to become part of these collaborations. The twelve projects comprising my proposed research program, encompass six long-term objectives designed to address issues around timing of migration and extinction related to Permian climate changes, and in so doing provide a template for all other stratigraphic studies. This is accomplished by investigating regions around the world, specifically western Canada, mid-continent USA, and south China. These areas were once part of the ancient Tethys Sea and the eastern margin of the Panthalassic Ocean (similar to the Mediterranean Sea and Pacific Ocean today). Many projects involve a field component, but will also use archived materials. All projects include laboratory research involving the recovery of conodonts and other fossils from the rock matrix, and include collection of additional geochemical data. The details of timing – from the small fossil clocks we discover in the rock – can then be used to decipher the history of basins around the world, as well as their potential for energy resources. It allows us to see not just Earth's history, but also our possible future.