Intense and widespread seismicity during the end-Triassic mass extinction due to emplacement of a large igneous province

Abstract

Multiple levels of earthquake-induced soft-sediment deformations (seismites) are concentrated in the end-Triassic mass extinction interval across Europe. The repetitive nature of the seismites rules out an origin by an extraterrestrial impact. Instead, this intense seismic activity is linked to the formation of the Central Atlantic magmatic province (CAMP). By the earliest Jurassic the seismic activity had ceased, while extrusive volcanism still continued and biotic recovery was on its way. This suggests that magmatic intrusions into sedimentary strata during early stages of CAMP formation caused emission of gases (SO<inf>2</inf>, halocarbons, polycyclic aromatic hydrocarbons) that may have played a major part in the biotic crisis.