|Title||The Emeishan large igneous province eruption triggered coastal perturbations and the Capitanian mass extinction: Insights from mercury in Permian bauxite beds|
|Author||Ling, K; Wen, H; Grasby, S E; Zhao, H; Deng, C; Yin, R|
|Source||Chemical Geology (Isotope Geoscience Section) vol. 617, 121243, 2022 p. 1-9, https://doi.org/10.1016/j.chemgeo.2022.121243|
|Alt Series||Natural Resources Canada, Contribution Series 20220564|
|Media||paper; digital; on-line|
|Lat/Long WENS|| 100.0000 110.0000 30.0000 20.0000|
|Subjects||geochemistry; igneous and metamorphic petrology; mercury; mercury geochemistry; igneous rocks; igneous petrology; bauxite|
|Illustrations||location maps; photographs; photomicrographs; lithologic logs; plots; cross-sections|
|Program||GEM2: Geo-mapping for Energy and Minerals Western Arctic, High Arctic LIP|
|Released||2022 11 30|
|Abstract||The Capitanian mass extinction occurring at the mid-Capitanian to the Guadalupian-Lopingian boundary (GLB; ca. 262-257 Ma) was temporally coincident with the eruption of the Emeishan large igneous
province (LIP). Recent observation of Hg anomalies at the GLB at shelf and slope/basinal settings demonstrated a possible causal link between the Capitanian extinction and the Emeishan LIP eruption. However, Hg records of the GLB at coastal settings
remain uninvestigated, limiting our knowledge of global impact of the Emeishan LIP and its role in the Capitanian mass extinction. Here we report new datasets of Hg concentrations, Hg isotopes and organic carbon isotopes in two coastal shallow-water
sections in the Guangxi region, SW China. Elevated Hg/TOC ratios (up to 3330 and 221 ppb/wt%, respectively) and near-zero to positive delta 199Hg values (- 0.04 per mil to +0.26 per mil) were observed across the GLB in the two sections, indicative of
extensive volcanic Hg input to the ocean via wet Hg(II) deposition. A negative d13Corg excursion (2.5 per mil) coincides with widespread marine anoxia, peak Emeishan LIP magmatism, Hg/TOC anomalies, sea-level rise, and the Capitanian mass extinction.
The temporal link between these phenomena suggests that the Emeishan LIP was a key driver of the climate/ocean dynamics, global ecosystems, and the formation of bauxite beds during the GLB. |
|Summary||(Plain Language Summary, not published)|
Increasingly data are showing that in deep time, large volcanic eruptions have driven a series of mass extinction events over the last 600 million years.
Understanding how these large eruptions affected the global environment can aid our understanding of potential impacts of modern industrialization and climate change. NRCan researchers have previously developed a unique tool to track the impact of
volcanism on the environment, using mercury and its isotopes as a fingerprint of volcanic emissions. In this study mercury is used to link eruption of the Emeishan Large Igneous Province with what is called the Capitanian mass extinction, which
occurred ~262 million years ago.