Magnitude and consequences of volatile release from the Siberian Traps

The eruption of the Siberian Traps flood basalts has been invoked as a trigger for the catastrophic end-Permian mass extinction. Quantitative constraints on volatile degassing are critical to understanding the environmental consequences of volcanism. We measured sulfur, chlorine, and fluorine in melt inclusions from the Siberian Traps and found that concentrations of these volatiles in some magmas were anomalously high compared to other continental flood basalts. For the ten samples for which we present data, volatile concentrations in individual melt inclusions range from less than the detection limit to 0.51 wt.% S, 0.94 wt.% Cl, and 1.95 wt.% F. Degassing from the Siberian Traps released approximately similar to 6300-7800 Gt S, similar to 3400-8700 Gt Cl, and similar to 7100-13,600 Gt F. These large volatile loads, if injected into the stratosphere, may have contributed to a drastic deterioration in global environmental conditions during the end-Permian. (C) 2011 Elsevier B.V. All rights reserved.