Use of single-grain geochemistry of cryptic tuffs and volcaniclastic sandstones improves the tephrostratigraphic framework of Olduvai Gorge, Tanzania.

Journal article
(Original article)


Publication Details

Author(s): Mchenry LJ, Stollhofen H, Stanistreet IG
Journal: Quaternary Research
Publisher: Elsevier
Publication year: 2013
Volume: 80
Pages range: 235-249
ISSN: 0033-5894
Language: English


Abstract


Single-grain geochemical composition of volcaniclastic sandstones can be a potential tool to improve correlations of mixed pyroclastic/epiclastic deposits. To test this, trachytic tuffs of the paleoanthropologically important FLK, FLK N, and FLK NN sites of Pleistocene Olduvai Gorge Bed I (Tanzania) are used as an established tephrostratigraphic framework against which to test volcaniclastic sandstone correlations. Fluvio-lacustrine sandstones and tuff samples were collected from eight archeological trenches between Tuffs IB and ID across a 500-m transect, including Leakey's famous Zinjanthropus (FLK) and OH 7/OH 8 (FLK NN) sites. A previously unknown, thin, fine, mineralogically unique, black trachyandesitic fallout ash was discovered below Tuff IC. Compositions of individual augite, feldspar and titanomagnetite grains from sandstones between Tuffs IB and IC reveal some IB-equivalent material, and a new compositional assemblage distinct from the sandwiching marker tuffs. Mineral compositions of the "tripartite" volcaniclastic sandstone between Tuffs IC and ID are similar to ID. Volcaniclastic sandstone grain fingerprints further refine correlations between fluvio-lacustrine sections within the area, providing support for proposed high-resolution stratigraphic reconstruction of the Zinjanthropus and OH 7/OH 8 land surfaces. This method might be applied to other sections where pyroclastic particles are admixed but distinct tuffs are not preserved. © 2013 University of Washington.



FAU Authors / FAU Editors

Stollhofen, Harald Prof. Dr.
Lehrstuhl für Geologie (Exogene Dynamik)


External institutions
The University of Liverpool
University of Wisconsin - Madison


How to cite

APA:
Mchenry, L.J., Stollhofen, H., & Stanistreet, I.G. (2013). Use of single-grain geochemistry of cryptic tuffs and volcaniclastic sandstones improves the tephrostratigraphic framework of Olduvai Gorge, Tanzania. Quaternary Research, 80, 235-249. https://dx.doi.org/10.1016/j.yqres.2013.05.006

MLA:
Mchenry, Lindsay J., Harald Stollhofen, and Ian G. Stanistreet. "Use of single-grain geochemistry of cryptic tuffs and volcaniclastic sandstones improves the tephrostratigraphic framework of Olduvai Gorge, Tanzania." Quaternary Research 80 (2013): 235-249.

BibTeX: 

Last updated on 2018-07-08 at 05:09