Examining the volcanism-extinction link: an end-Guadalupian case study

Is volcanism capable of causing species to go extinct? We don't know the answer to this question but evidence from rocks provides some intriguing clues. Thus, it has been recognised that all the extinction events of the past 300 million years coincide with major volcanic eruptions. These eruptions consisted of huge flows of basalt, involving 100s or 1000s of cubic kilometres of lava, that quietly oozed from the ground, plus some much more violent eruptions that scattered volcanic ash over great distances. Working out which of these styles of eruption are most closely associated, in time, with the extinctions has proved very difficult because the fossil evidence is usually found far away from where the volcanism occurred. This project will address this problem by studying a unique example of the volcanism-extinction link from 260 million years ago when lavas and ashes were repeatedly erupted into shallow seas in present-day China. The limestones that formed in these seas contain abundant fossils and evidence of a catastrophic extinction. By studying these Chinese rocks it will be possible, for the first time, to study directly both the volcanism and extinction story in the same place. The work will be supplemented with studies of carbon and sulphur isotopes from the limestones which will allow the scientists to determine changes in the state of the oceans during this interval.