Plio-Pleistocene microtephra in DSDP Site 231, Gulf of Aden

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doi: 10.1016/j.jafrearsci.2007.05.004
Author(s): Feakins, Sarah J.; Brown, Francis H.; deMenocal, Peter B.
Author Affiliation(s): Primary:
Lamont-Doherty Earth Observatory, Palisades, NY, United States
University of Utah, United States
Volume Title: Journal of African Earth Sciences
Source: Journal of African Earth Sciences, 48(5), p.341-352. Publisher: Elsevier, Oxford, United Kingdom. ISSN: 1464-343X
Note: In English. 68 refs.; illus., incl. 3 tables, geol. sketch map
Summary: We reconstruct a Plio-Pleistocene microscopic tephrostratigraphy for DSDP Site 231 in the Gulf of Aden. Systematic microtephrostratigraphy increases the potential for identifying tephra horizons for regional stratigraphic correlation and age control, as well as providing information about eruptive histories. Microtephra reveal three main pulses of volcanism c. 4.0-3.2 Ma, 2.4 Ma and 1.7-1.3 Ma, corresponding to peaks in volcanic activity recorded in the East African Rift System. Previous studies of DSDP Site 231 have reported six visible tephra horizons (up to 25 cm thick) with geochemical compositions matching East African tuffs. We find 68 additional microtephra horizons through microscopic examination of 1050 samples (each integrating c. 3 ka) in over 200 m of marine sediments. We report the major and minor element geochemical compositions of individual glass shards in six of these microtephra horizons and establish a robust correlation at 168.73 m to the Lokochot Tuff (3.58 Ma), which together with previously identified tephra, provides a tightly constrained chronostratigraphy for the mid Pliocene. Abstract Copyright (2007) Elsevier, B.V.
Year of Publication: 2007
Research Program: DSDP Deep Sea Drilling Project
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Africa; Arabian Sea; Cenozoic; DSDP Site 231; Deep Sea Drilling Project; Electron probe data; Glasses; Gulf of Aden; Igneous rocks; Indian Ocean; Leg 24; Neogene; Pleistocene; Pliocene; Quaternary; Tephrostratigraphy; Tertiary; Volcanic glass; Volcanic rocks; Volcaniclastics
Coordinates: N115304 N115305 E0481443 E0481442
Record ID: 2008127765
Copyright Information: GeoRef, Copyright 2017 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands