U.S.-France Planning Visit: Investigating Upland Glaciation in the Pangaean Tropics

University Of Oklahoma Norman Campus, Norman OK

Investigators

Abstract

The objective of this international planning grant is to meet with French colleagues and conduct a reconnaissance field trip to investigate Late Paleozoic paleoclimate in sedimentary rocks of the Central Pangaean mountains (Massif Central region), with the aim of developing a future international collaboration on this topic. The Late Paleozoic (Pennsylvanian-Permian) records Earth?s most recent example of so-called ?icehouse? conditions, in which atmospheric CO2 levels were low and glaciation persisted at high latitudes, similar to Earth?s current and recent state. Moreover, the Late Paleozoic (300 million years ago) is Earth?s last example of the transition from a planet that hosted large ice sheets and alpine glaciers to one that was essentially ice-free. Although the former existence of Late Paleozoic ice sheets in high-latitude regions has been long accepted, the existence of glaciation at low latitudes is in question; if ice existed in the tropics, then our models for Earth?s climate behavior during this time require revision. This project stems from independent work by PI Soreghan in the U.S., and geoscientists in France, on the hypothesis of glaciation in the Late Paleozoic tropics -- i.e., the mountains of low-latitude Pangaea, which spanned from Europe to North America. The hypothesis of alpine glaciation in the Permo-Pennsylvanian strata of France dates back a century, but has only resurfaced in the last few years, coincident with Soreghan?s work in the U.S. This travel grant is to begin a new research collaboration, building upon incidental email exchanges between Soreghan and French colleagues over the last year. The project will occur in three phases, as follows: 1) initial planning, involving all collaborators, via email and video-conferencing; 2) the planning visit, involving PI Soreghan, and three students from the University of Oklahoma (undergraduate and graduate). This visit will involve colloquia at the French institutions, followed by a day field excursion to canvass research localities. 3) Post-trip activities will entail data analysis in U.S. and French labs, and data sharing with the intent of developing a future research project to undertake a comprehensive assessment of those localities that show the best promise for preserving an upland record of paleoclimate. Intellectual Merit: If results continue to indicate glaciation in upland tropical Pangaea, then this implies an enormous shift in long-accepted reconstructions of Pangaean climate. The Late Paleozoic Ice Age is Earth?s most recent pre-Quaternary glaciation, and thus a common target for climate modelers, using the same models as those employed to predict future climate. Hence, calibrations to these models are critical for understanding broader aspects of Earth?s climate system. Broader Impacts: The collaborative research will enhance the research skills of both U.S. and French collaborators. A planning trip to France, with the promise of a longer-term research project, will afford participating US students from OU an extraordinary opportunity to experience both the scientific experience of inception of an interdisciplinary, international research collaboration, and the cultural experience of visiting and conducting geology in a foreign locale. The proposed research will contribute to the experience base and expertise in sedimentologic and tectonic analyses of all collaborators, while developing datasets and results that will assist a number of other researchers and research projects.