EGU2020-11830, updated on 05 Jan 2021
EGU General Assembly 2020
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

DeepDust - A Proposed Drilling Project to Probe Continental Climate of the Late Paleozoic Icehouse-Greenhouse Transition

Gerilyn Soreghan1, Laurent Beccaletto2, Kathleen Benison3, Sylvie Bourquin4, Natsuko Hamamura5, Michael Hamilton6, Nicholas Heavens7, Linda Hinnov8, Cindy Looy9, Lily Pfeifer10, and Stephane Pochat11
Gerilyn Soreghan et al.
  • 1Geosciences, University of Oklahoma, United States of America (
  • 2BRGM, F-45060 Orléans, France, (
  • 3Geology & Geography, West Virginia University, United States of America (
  • 4CNRS, Géosciences Rennes, Univ Rennes, France (
  • 5Biology, Kyushu University, Japan (
  • 6Earth Sciences, University of Toronto, Canada (
  • 7Space Science Institute, United States of America (
  • 8Atmospheric, Oceanic, and Earth Sciences, George Mason University, United States of America (
  • 9Integrative Biology, Museum of Paleontology, University of California Berkeley, United States of America (
  • 10Geosciences, University of Oklahoma, United States of America (
  • 11LPG- UMR CNRS, Université de Nantes, France (

The climatic, biotic, and tectonic events of the Permian are amongst the most profound in Earth history. Global orogeny leading to Pangaean assembly culminated by middle Permian time, and included multiple orogenic belts in the equatorial Central Pangaean Mountains, from the Variscan-Hercynian system (east) to the Ancestral Rocky Mountains (west). Earth’s penultimate global icehouse peaked in early Permian time, transitioning to full greenhouse conditions by late Permian time, thus archiving the only example of icehouse collapse on a fully vegetated Earth. The Late Paleozoic Icehouse was the longest and most intense glaciation of the Phanerozoic, with hypothesized low-elevation glaciation posited for both eastern and western tropical Pangaea during early Permian time. Reconstructions of atmospheric composition record the lowest CO2 and highest O2 levels of the Phanerozoic, with average CO2 levels comparable to the Quaternary, rapidly warming climate. Fundamental shifts occurred in atmospheric circulation: a global megamonsoon developed and the tropics became anomalously arid with time. Extreme environments are well documented in the form of voluminous dust deposits, acid-saline lakes and groundwaters, extreme continental temperatures and aridity, and major extinctions/extirpations, ultimately culminating at the Permo-Triassic boundary with the largest extinction of Earth history.

We seek to elucidate paleoclimatic conditions and forcings through the Permian at temporal scales ranging from the millennial to the Milankovitch  and beyond by acquiring continuous core in continental lowlands known to harbor stratigraphically complete records dominated by loess and lacustrine strata. We have identified sites in the western U.S. and Europe as the key sites globally to achieve our objectives, as these represent the western and eastern limits, respectively of the Pangaean tropics. Identified sites harbor arguably the most complete continental Permian sections in the paleoequatorial region, with adjacent paleo-uplands hypothesized to have hosted glaciation. We will also address the nature and character of the modern and fossil microbial biosphere, Mars-analog conditions, and exhumation histories of source regions.

How to cite: Soreghan, G., Beccaletto, L., Benison, K., Bourquin, S., Hamamura, N., Hamilton, M., Heavens, N., Hinnov, L., Looy, C., Pfeifer, L., and Pochat, S.: DeepDust - A Proposed Drilling Project to Probe Continental Climate of the Late Paleozoic Icehouse-Greenhouse Transition, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11830,, 2020


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