Revisiting the age of the mafic intrusive magmatism in the Paraná Magmatic Province through high-precision U-Pb geochronology

Abstract

The temporal link between the mafic intrusive component of Large Igneous Provinces (LIP) and global climate disturbances eventually leading to mass extinctions has been demonstrated for several LIPs (i.e. Siberian Traps, CAMP). The Paraná-Etendeka LIP had less catastrophic effects with only a minor marine extinction during the Valanginian oceanic anoxic event. The release of greenhouse gases (CO2, CH4) during LIP emplacement may be enhanced by the interaction of sub-volcanic intrusives (sills and dyke swarms) and volatile-rich host-rocks such as organic-rich shales, coal and evaporites. This proposal aims to determine high-precision zircon U-Pb CA-ID-TIMS ages in selected mafic intrusive rocks from the Paraná Magmatic Province (PMP), including the Florianópolis Dyke Swarm, Limeira and Jaguariúna Sills, basic pegmatites correlated to Paranapanema basalts, and layered intrusions correlated to Esmeralda (low-Ti) and Pitanga (high-Ti) basalts. This proposal will be carried out at the University of Geneva (Switzerland), under the supervision of Professor Urs Schaltegger. The proposed study will complement the high-precision dataset from silicic volcanic rocks to allow additional testing of temporal correlation of PMP magmatism with the Valanginian Event and will contribute to a better understanding of the environmental impact of the PMP volcanism. (AU)