Great Volcano Eruptions in Earth History

When you compare the age of LIPs with the estimated ages of stratigraphic boundaries involving significant biotic changes (dated according to the most recent geological time scale), in at least three cases (the Deccan, Newark, and Siberian flood basalts), a direct measure of correlation with major extinction events is possible (see graph below). The probability that three major volcanic events that typically last ~1 Myr should occur within 1 Myr of major extinction events during the last 250 Myr (of which there are ~12) is about 10^-4. Thinking about the ways in which these two types of global event might be causally linked is a worthy scientific challenge.