GSA Annual Meeting in Seattle, Washington, USA - 2017

Paper No. 228-9
Presentation Time: 3:30 PM

THE MIDDLE PERMIAN (CAPITANIAN) EXTINCTION RECORD IN THE BOREAL REALM (SPITSBERGEN AND ELLESMERE ISLAND): EVIDENCE FOR VOLCANICALLY-DRIVEN KILL MECHANISMS


BOND, David P.G., School of Environmental Sciences, University of Hull, Hull, HU6 7RX, United Kingdom, WIGNALL, Paul B., School of Earth and Environment, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, United Kingdom and GRASBY, Stephen E., Geological Survey of Canada, 3303 33 St NW, Calgary, AB T2L 2A7, Canada, d.bond@hull.ac.uk

The Middle Permian (Capitanian, ca. 262 Ma) mass extinction, mostly known from equatorial paleolatitudes, was recently identified in a Boreal (northern mid-to-high paleolatitude) setting in Spitsbergen. We document this extinction in the fossil record from Ellesmere Island (Canada), which, like Spitsbergen was situated on the NW margins of Permian Pangaea. Our data confirms Middle Permian losses as a global crisis on par with the “Big Five”. Redox proxies (pyrite framboids and trace metals) show that the high latitude crisis coincided with an intensification of oxygen-poor conditions - a potent killer, but one that is not clearly developed in lower latitude sections. Mercury, a useful proxy for large-scale volcanism, becomes briefly enriched at the level of the Middle Permian extinction level in both Spitsbergen and Ellesmere Island. This was potentially derived from the emplacement of the Emeishan large igneous province (LIP) in SW China, supporting a causal link between volcanism and extinction. Thus, a potent cocktail of poisons appears to have impacted across the Boreal Realm, whilst the near-total loss of carbonates near the extinction level is also consistent with reduced pH across the region. Multiple stresses, possibly with origins in low-latitude volcanism, are therefore implicated in the Middle Permian extinction and there was no respite even in the far-distant Boreal Realm.