New evidence suggests volcanoes caused biggest mass extinction ever
Mercury found in ancient rock around the world supports theory that
eruptions caused 'Great Dying' 252 million years ago. University of
Cincinnati, Science Daily, April 15, 2019
https://www.sciencedaily.com/releases/2019/04/190415122249.htm
The open access paper is:
Jun Shen, Jiubin Chen, Thomas J. Algeo, Shengliu Yuan, Qinglai Feng,
Jianxin Yu, Lian Zhou, Brennan O’Connell, Noah J. Planavsky. Evidence
for a prolonged Permian–Triassic extinction interval from global mar