Now showing items 1-2 of 2

    • Chuar Group of the Grand Canyon: Record of Breakup of Rodinia, Associated Change in the Global Carbon Cycle, and Ecosystem Expansion by 740 Ma 

      Karlstrom, Karl E.; Bowring, Samuel A.; Dehler, Carol M.; Knoll, Andrew; Porter, Susannah M.; Des Marais, David J.; Weil, Arlo B.; Sharp, Zachary D.; Geissman, John W.; Elrick, Maya B.; Timmons, J. Michael; Crossey, Laura J.; Davidek, Kathleen L. (Geological Society of America, 2000)
      The Chuar Group (similar to 1.600 m thick) preserves a record of extensional tectonism, ocean-chemistry fluctuations, and biological diversification during the late Neoproterozoic Era. An ash layer from the top of the ...
    • Molybdenum evidence for expansive sulfidic water masses in ~750Ma oceans 

      Dahl, Tais; Canfield, Donald E.; Rosing, Minik T.; Frei, Robert E.; Gordon, Gwyneth W.; Knoll, Andrew Herbert; Anbar, Ariel D. (Elsevier BV, 2011)
      The Ediacaran appearance of large animals, including motile bilaterians, is commonly hypothesized to reflect a physiologically enabling increase in atmospheric and oceanic oxygen abundances (pO2). To date, direct evidence ...