Chronostratigraphy of the Miocene–Pliocene Sagantole Formation, Middle Awash Valley, Afar rift, Ethiopia

Research Article| June 01, 1999 Chronostratigraphy of the Miocene–Pliocene Sagantole Formation, Middle Awash Valley, Afar rift, Ethiopia Paul R. Renne; Paul R. Renne 1Berkeley Geochronology Center, 2455 Ridge Road, Berkeley, California 947092Department of Geology and Geophysics, University of California, Berkeley, California 94720 Search for other works by this author on: GSW Google Scholar Giday WoldeGabriel; Giday WoldeGabriel 3Los Alamos National Laboratory, Los Alamos, New Mexico 87545 Search for other works by this author on: GSW Google Scholar William K. Hart; William K. Hart 4Department of Geology, Miami University, Oxford, Ohio 45056 Search for other works by this author on: GSW Google Scholar Grant Heiken; Grant Heiken 3Los Alamos National Laboratory, Los Alamos, New Mexico 87545 Search for other works by this author on: GSW Google Scholar Tim D. White Tim D. White 5Laboratory for Human Evolutionary Studies, Museum of Vertebrate Zoology6Department of Integrative Biology, University of California, Berkeley, California 94720 Search for other works by this author on: GSW Google Scholar Author and Article Information Paul R. Renne 1Berkeley Geochronology Center, 2455 Ridge Road, Berkeley, California 947092Department of Geology and Geophysics, University of California, Berkeley, California 94720 Giday WoldeGabriel 3Los Alamos National Laboratory, Los Alamos, New Mexico 87545 William K. Hart 4Department of Geology, Miami University, Oxford, Ohio 45056 Grant Heiken 3Los Alamos National Laboratory, Los Alamos, New Mexico 87545 Tim D. White 5Laboratory for Human Evolutionary Studies, Museum of Vertebrate Zoology6Department of Integrative Biology, University of California, Berkeley, California 94720 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1999) 111 (6): 869–885. https://doi.org/10.1130/0016-7606(1999)111<0869:COTMPS>2.3.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Paul R. Renne, Giday WoldeGabriel, William K. Hart, Grant Heiken, Tim D. White; Chronostratigraphy of the Miocene–Pliocene Sagantole Formation, Middle Awash Valley, Afar rift, Ethiopia. GSA Bulletin 1999;; 111 (6): 869–885. doi: https://doi.org/10.1130/0016-7606(1999)111<0869:COTMPS>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The Sagantole Formation comprises more than 200 m of lacustrine, alluvial, and volcaniclastic sediments, plus compositionally bimodal tephras and basaltic lavas, exposed in a domelike horst named the Central Awash Complex in the southwestern Afar rift of Ethiopia. The Sagantole Formation is widely known for abundant vertebrate faunas, including the 4.4 Ma primitive hominid Ardipithecus ramidus. New lithostratigraphic data are used to subdivide the Sagantole Formation into the Kuseralee, Gawto, Haradaso, Aramis, Beidareem, Adgantole, and Belohdelie Members, in ascending order. The members are defined on the basis of lithologic differences and laterally continuous bounding tephras.40Ar/39Ar dating of 12 intercalated volcanic units firmly establishes the age of the Sagantole Formation to be 5.6 to 3.9 Ma, significantly older than previous proposals based on erroneous correlations. Magnetostratigraphic data reveal eight paleomagnetic polarity zones, which can be correlated unambiguously with the Thvera, Sidufjall, Nunivak, and Cochiti Subchrons of the Gilbert Chron. Thus, by reference to the geomagnetic polarity time scale, seven additional chronological datums can be placed in the Sagantole Formation. With a total of 19 such datums, the age resolution anywhere in the Sagantole Formation is better than ±100 k.y., making this the best-dated Miocene–Pliocene succession in Africa. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.