Hadar Formation Deposits at Ledi-Geraru, Afar, Ethiopia
Journal of African Earth Sciences 112 (2015) 234e250 Contents lists available at ScienceDirect Journal of African Earth Sciences journal homepage: www.elsevier.com/locate/jafrearsci Tephrostratigraphy and depositional environment of young (<2.94 Ma) Hadar Formation deposits at Ledi-Geraru, Afar, Ethiopia * Erin N. DiMaggio a, , J Ramon Arrowsmith b, Christopher J. Campisano c, Roy Johnson d, Alan L. Deino e, Mark Warren f, Shimeles Fisseha g, Andrew S. Cohen d a Department of Geosciences, Pennsylvania State University, University Park, PA 16802, USA b School of Earth and Space Exploration, Arizona State University, P.O. Box 871404, Tempe, AZ 85287, USA c Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, P.O. Box 874101, Tempe, AZ 85287, USA d Department of Geosciences, University of Arizona, 1040 E. 4th Street, Tucson, AZ 85721, USA e Berkeley Geochronology Center, 2455 Ridge Road, Berkeley, CA 94709, USA f ConocoPhillips, 600 N Dairy Ashford, Houston, TX 77079, USA g Institute of Geophysics, Space Sciences and Astronomy, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia article info abstract Article history: The Pliocene Hadar Formation, exposed throughout the lower Awash Valley, Ethiopia, chronicles the Received 23 January 2015 evolution and paleoenvironmental context of early hominins. Deposition of the Hadar Formation Received in revised form continued until at least 2.94 Ma, but what transpired in the Hadar Basin after this time remains poorly 21 September 2015 documented due to an erosional event that truncated the formation throughout much of the valley. Here Accepted 22 September 2015 we present geologic mapping and stratigraphic analysis of a 26 m-thick section of sedimentary rocks and Available online 30 September 2015 tephras exposed in the Ledi-Geraru project area in the region of Gulfaytu.
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