Climate instability and tipping points in the Late Devonian: Detection of the Hangenberg Event in an open oceanic island arc in the Central Asian Orogenic Belt
- ASU Author/Contributor (non-ASU co-authors, if there are any, appear on document)
- Sarah K. Carmichael Ph.D., Assistant Professor of Geology (Creator)
- Johnny A. Waters Ph.D., Professor: Invertebrate Paleontology (Creator)
- Institution
- Appalachian State University (ASU )
- Web Site: https://library.appstate.edu/
Abstract: Sedimentary petrology and trace element geochemistry indicate that the Late Devonian to Early Carboniferous Heishantou Formation near Boulongour Reservoir (NW Xinjiang, China) was deposited on a steep slope, mid-latitude accreting island arc complex in an open oceanic system. Bulk 87Sr/86Sr ratios show excursion patterns that are consistent with excursions at the Devonian–Carboniferous (D–C) boundary in epicontinental margin sediments. Sedimentation rates for the Boulongour Reservoir sediments show highly variable rates that range from 0.5 cm/ky to 10 cm/ky, consistent with other Late Devonian sections and modern arc environments. Multiple whole rock geochemical proxies for anoxia and the size and distribution of pyrite framboids suggest the presence of the Hangenberg Event in the sediments associated with the D–C boundary, despite the lack of visible black shale. The presence of anoxia in an open ocean, island arc environment cannot be explained by upwelling of anoxic bottom waters at this paleolatitude, but can be explained by the global in?iction of oceanic shallow water eutrophication on to a climate system in distress.
Climate instability and tipping points in the Late Devonian: Detection of the Hangenberg Event in an open oceanic island arc in the Central Asian Orogenic Belt
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Created on 4/3/2015
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Additional Information
- Publication
- Sarah K. Carmichael, Johnny A. Waters, Cameron J. Batchelor, Drew M. Coleman, Thomas J. Suttner, Erika Kido, L.M. Moore, Leona Chadimová,(2015)Climate instability and tipping points in the Late Devonian: Detection of the Hangenberg Event in an open oceanic island arc in the Central Asian Orogenic Belt, Gondwana Research, The copy of record is available from Elsevier(18 March 2015), ISSN 1342-937X, http://dx.doi.org/10.1016/j.gr.2015.02.009.
- Language: English
- Date: 2015
- Keywords
- Devonian–Carboniferous,
Chemostratigraphy,
Central Asian Orogenic Belt,
West Junggar,
Hangenberg Event,