Possible correlation of Oligocene climate changes with Ethiopian Oligocene ignimbrite eruptions

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doi: 10.1007/s12517-011-0307-6
Author(s): Ayalew, Dereje
Author Affiliation(s): Primary:
Addis Ababa University, Department of Earth Sciences, Addis Ababa, Ethiopia
Volume Title: Arabian Journal of Geosciences
Source: Arabian Journal of Geosciences, 5(5), p.999-1002. Publisher: Springer, Berlin-Heidelberg, Saudi Arabia. ISSN: 1866-7511
Note: In English. 25 refs.; illus., incl. sketch map
Summary: The Oligocene Ethiopian continental flood basalt province (ca. 29-31 Ma) contains significant silicic pyroclastic rocks (>60,000 km3 constituting up to 20% of the volcanic stratigraphy). Rhyolitic tephras, synchronous with the Ethiopian silicic pyroclastic rocks, are found in Indian Ocean ODP holes 711A. They are geochemically akin to the Ethiopian silicic pyroclastic rocks. This suggests that the Indian Ocean tephras originated from Ethiopian silicic eruptions and represents more distal fallout of this volcanism. The temporal coincidence of the Ethiopian flood volcanism with the Oligocene global cooling event (Oi2 ∼ 30.3 Ma) and the emplacement of the Ethiopian silicic pyroclastic eruptions on a near-global scale strongly suggest that the Ethiopian continental flood basalt province may have contributed or at least accelerated the climate change that was already underway. Copyright 2011 Saudi Society for Geosciences
Year of Publication: 2012
Research Program: ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Africa; Basalts; Cenozoic; Climate change; East Africa; Eruptions; Ethiopia; Flood basalts; Igneous rocks; Ignimbrite; Indian Ocean; Leg 115; ODP Site 711; Ocean Drilling Program; Oligocene; Paleoclimatology; Paleogene; Pyroclastics; Tertiary; Volcanic rocks; Volcanism
Coordinates: S024434 S024433 E0610947 E0610946
N000000 N200000 E0500000 E0300000
Record ID: 2015068135
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data supplied by Springer Verlag, Berlin, Federal Republic of Germany