New single crystal 40Ar/39Ar ages improve time scale for deposition of the Omo Group, Omo–Turkana Basin, East Africa

  title={New single crystal 40Ar/39Ar ages improve time scale for deposition of the Omo Group, Omo–Turkana Basin, East Africa},
  author={Ian Mcdougall and Francis H. Brown and Paulo Marcos Vasconcelos and Benjamin E. Cohen and D. S. Thiede and Michael J. Buchanan},
  journal={Journal of the Geological Society},
  pages={213 - 226}
Six tuffaceous beds within the Omo Group of the Omo–Turkana Basin have been dated using the 40Ar/39Ar single crystal total fusion method on anorthoclase, yielding eruption ages. The Omo Group constitutes up to 800 m of subaerially exposed sediments surrounding Lake Turkana within the East African Rift system in northern Kenya and southern Ethiopia. Rhyolitic explosive eruptions produced tuffs and pumice clasts that are considered to have been deposited shortly after eruption. The new age data… Expand

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