The blue lines shows the rate of extinctions over time, clearly showing several mass extinctions. The red bars show the known flood basalt eruptions, most recently that of the Columbia River. The largest extinctions coincide with flood basalt events. The relation is not conclusive: better dates would be needed how well they coincide. But it is suggestive. Original at https://www.le.ac.uk/gl/ads/SiberianTraps/Images/LIPsExtinctions_jpg_files/LIPsExtinctions.jpg (University of Leeds)