| Title | Episodic photic zone euxinia in the northeastern Panthalassic Ocean during the end-Triassic extinction |
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| Author | Kasprak, A H; Sepúlveda, J; Price-Waldman, R; Williford, K H; Schoepfer, S D; Haggart, J W; Ward, P D; Summons, R E; Whiteside, J H |
| Source | Geology vol. 43, no. 4, 2015 p. 307-310, https://doi.org/10.1130/G36371.1  Open Access |
| Image |  |
| Year | 2015 |
| Alt Series | Earth Sciences Sector, Contribution Series 20130148 |
| Publisher | Geological Society of America |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | British Columbia; Alberta; Saskatchewan; Manitoba; Ontario; Quebec; New Brunswick; Nova Scotia; Prince Edward Island; Newfoundland and Labrador; Northwest Territories; Yukon; Nunavut; Canada |
| NTS | 1; 2; 3; 10; 11; 12; 13; 14; 15; 16; 20; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 52; 53; 54; 55; 56; 57; 58; 59; 62; 63; 64; 65;
66; 67; 68; 69; 72; 73; 74; 75; 76; 77; 78; 79; 82; 83; 84; 85; 86; 87; 88; 89; 92; 93; 94; 95; 96; 97; 98; 99; 102; 103; 104; 105; 106; 107; 114O; 114P; 115; 116; 117; 120; 340; 560 |
| Area | WORLD |
| Lat/Long WENS | -180.0000 180.0000 90.0000 -90.0000 |
| Subjects | paleontology; extinctions, biotic; Panthalassic Ocean; Tethys Ocean; Mesozoic; Triassic |
| Illustrations | graphs; diagrams |
| Program | GSC Pacific Division |
| Released | 2015 04 01 |
| Abstract | Severe changes in ocean redox, nutrient cycling, and marine productivity accompanied most Phanerozoic mass extinctions. However, evidence for marine photic zone euxinia (PZE) as a globally important
extinction mechanism for the end-Triassic extinction (ETE) is currently lacking. Fossil molecular (biomarker) and nitrogen isotopic records from a sedimentary sequence in western Canada provide the first conclusive evidence of PZE and disrupted
biogeochemistry in neritic waters of the Panthalassic Ocean during the end Triassic. Increasing water-column stratification and deoxygenation across the ETE led to PZE in the Early Jurassic, paralleled by a perturbed nitrogen cycle and ecological
turnovers among noncalcifying groups, including eukaryotic algae and prokaryotic plankton. If such conditions developed widely in the Panthalassic Ocean, PZE might have been a potent mechanism for the ETE. |
| Summary | (Plain Language Summary, not published)
Significant changes in oceanic environmental conditions have accompanied most mass extinctions of life during the Phanerozoic Era, from 540 million years
ago to the present. By analyzing the geochemical characteristics of rocks that are preserved today on Haida Gwaii, British Columbia, and which formed at the end of the Triassic Period approximately 200 million years ago, the authors have
demonstrated in this scientific paper that significant parts of the world¿s oceans were characterized by restricted hydrologic circulation during the latest Triassic. Such conditions would have resulted in stagnant or anaerobic conditions in the
world¿s oceans on a global level, which may have produced the significant extinction of marine life seen at the end of the Triassic Period. These rocks also often contain high levels of organic matter that is the source of oil and natural gas, so
understanding the mechanisms of their formation is important for petroleum exploration efforts. |
| GEOSCAN ID | 292794 |
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