Changes of palaeoenvironmental conditions recorded in Late Devonian reef systems from the Canning Basin,Western Australia: A biomarker and stable isotope approach |
| |
| Institution: | 1. Western Australian Organic and Isotope Geochemistry Centre, The Institute for Geoscience Research, Department of Chemistry, Curtin University, GPO Box U1987, Perth, WA 6845, Australia;2. Centre for Exploration Targeting and Western Australian Biogeochemistry Centre, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia;3. Geological Survey of Western Australia, Department of Mines and Petroleum, 100 Plain Street, East Perth, WA 600, Australia;4. Department of Geological Sciences, Indiana University, 1001 East 10th Street, Bloomington, IN 47405-1405, USA;5. Department of Earth, Atmospheric and Planetary Sciences, MIT, E25-633, 45 Carleton Street, Cambridge, MA 02139, USA;6. Geoscience Australia, GPO Box 378, Canberra, ACT 2601, Australia;7. School of Earth and Environment, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia;8. Geochemistry & Isotope Geochemistry Group, Marine Geology Department, Leibniz-Institute for Baltic Sea Research, Seestrasse 15, D-18119 Warnemünde, Germany;9. Chevron Energy Technology Company, Carbonate Stratigraphy Research & Development, 1500 Louisiana Street, Houston, TX 77002, USA;10. Institute of Geoscience, Kiel University, Ludewig-Meyn Str. 10, 24118 Kiel, Germany;1. Department of Geology, Appalachian State University, Boone, NC 28608, United States;2. Karl-Franzens-University of Graz, Institute for Earth Sciences (Geology & Paleontology), Heinrichstrasse 26, A-8010 Graz, Austria;3. Department of Geology & Geophysics, University of Utah, Salt Lake City, UT 84112, United States;1. Department of Geology, Appalachian State University, Boone, NC 28608, United States;2. Department of Geological Sciences, University of North Carolina - Chapel Hill, Chapel Hill, NC 27599-3315, United States;3. Karl-Franzens-University of Graz, Institute for Earth Sciences (Geology & Paleontology), Heinrichstrasse 26, A-8010 Graz, Austria;4. Institute of Geology Academy of Sciences of the Czech Republic, v.v.i., Rozvojova 269, 165 00 Prague 6, Czech Republic;1. The University of Tulsa, Department of Geosciences, Tulsa, OK 74104, United States;2. University of California—Riverside, Department of Earth Sciences, Riverside, CA 92521, United States;3. Virginia Polytechnic Institute and State University, Department of Geosciences, Blacksburg, VA 24061, United States;1. TU Bergakademie Freiberg, Geological Institute, Department Palaeontology/Stratigraphy, Bernhard-von-Cotta-Str. 2, 09599 Freiberg, Germany;2. Kazan Federal University, Kremlyovskaya str. 18, 420008 Kazan, Russia;3. Geology Department and Albany Museum, Rhodes University, Grahamstown 6140, South Africa;1. Syracuse University, 204 Heroy Geology Lab, 900 S Crouse Drive, Syracuse, NY 13210, United States;2. Winthrop University, 212B Sims Science Building, 876 Ebenezer Avenue, Rock Hill, SC 29733, United States;3. Williams College, 203 Clark Hall, 947 Main St, Williamstown, MA 01267, United States;4. Illinois State University, Femley Hall 206, Campus Box 4400, Normal, IL 61790-4400, United States |
| |
| Abstract: | Although the Late Devonian extinctions were amongst the largest mass extinction events in the Phanerozoic, the causes, nature and timing of these events remain poorly restrained. In addition to the most pronounced biodiversity loss at the Frasnian–Famennian (F–F) boundary and the end Famennian, there were also less extensively studied extinction pulses in the Middle to Late Givetian and the Frasnian. Here we used a combination of palynological, elemental, molecular and stable isotope analyses to investigate a sedimentary record of reef-systems from this time period in the Canning Basin, Western Australia.The acquired data generally showed distinct variations between sediments from (i) the time around the Givetian–Frasnian (G–F) boundary and (ii) later in the Frasnian and indicated a distinct interval of biotic stress, particularly for reef-builders, in the older sediments. Alterations of pristane/phytane ratios, gammacerane indices, Chlorobi biomarkers, δDkerogen and chroman ratios describe the change from a restricted marine palaeoenvironment with an anoxic/euxinic hypolimnion towards a presumably open marine setting with a vertically mixed oxic to suboxic water column. Simultaneous excursions in δ13C profiles of carbonates, organic matter (OM) and hydrocarbons in the older sediments reflect the stratification-induced enhancement of OM-recycling by sulfate reducing bacteria. Alterations in sterane distributions and elevated abundances of methyltrimethyltridecylchromans (MTTCs) and perylene indicate an increased terrigenous nutrient input via riverine influx, which would have promoted stratification, phytoplankton blooms and the development of lower water column anoxia.The detected palaeoenvironmental conditions around the G–F boundary may reflect a local or global extinction event. Our data furthermore suggest a contribution of the higher plant-expansion and photic zone euxinia to the Late Devonian extinctions, consistent with previous hypotheses. Furthermore, this work might contribute to the understanding of variations in Devonian reef margin and platform-top architecture, relevant for petroleum exploration and development in the global Devonian hydrocarbon resources. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
