Wednesday, September 10, 2014

Sulfur Very Important for Volcanicly Driven Mass Extinctions?

Microanalyses link sulfur from large igneous provinces and Mesozoic mass extinctions

Authors:

Callegro et al

Abstract:

Volcanic gases can have devastating impacts on Earth's environment and life. However, measurement of volatile elements in prehistoric magmas is challenging. We present a new method for determining sulfur contents in magmas using its concentrations in clinopyroxenes and an experimentally determined crystal-melt partition coefficient. Using this method we compared magmatic sulfur contents in the Paraná-Etendeka large igneous province (LIP; South America) and two other similarly sized LIPs, the Central Atlantic magmatic province (CAMP) and the Deccan Traps (India). We found that the CAMP and Deccan Traps, both associated with major extinction events, contained high magmatic sulfur concentrations, up to 1900 ppm. Conversely, the Paraná-Etendeka LIP, lacking significant environmental effects, had substantially lower magmatic sulfur concentrations, less than 800 ppm.

They ought to look at the Permian Extinction/Siberian Traps.  I am a bit surprised they did not.  And, again, the Deccan Traps have dinosaur fossils below, between and above the lava flows.

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