GSA Connects 2021 in Portland, Oregon

Paper No. 73-2
Presentation Time: 8:25 AM


KARLSTROM, Leif, Department of Earth Sciences, University of Oregon, 100 Cascade Hall, 1272 University of Oregon, Eugene, OR 97403, BLACK, Benjamin A., Earth and Environmental Sciences, The Graduate Center, City University of New York, New York, NY 10016 and MATHER, Tamsin A., Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN, United Kingdom

Extremely voluminous magmatic systems known as Large Igneous Provinces (LIPs) punctuate Earth’s history, and the gases they release link large-scale geodynamic and magmatic processes with major climate shifts in Earth’s geological record. Temporal variations in eruptive output originate in depths of mantle melting, volatile budgets, crustal rheology, and the magma transport processes that control proportions of intrusion versus eruption through the life cycle of LIPs. In this presentation, we review recent insights and major questions regarding the linked evolution of mantle melting, expansive magmatic systems, and the redistribution of volatiles from the solid Earth to the atmosphere. We present a new data compilation tracking volatile release from Phanerozoic LIPs, and we discuss how and why the tempo of gas release—a primary driver of environmental changes—can decouple from the tempo of volcanic activity. We draw on existing constraints on the evolution of LIP magmatic systems to characterize the life cycle of LIPs, and to relate this life cycle to other types of volcanism. We advocate for new, temporally resolved constraints on the evolution of LIP plumbing systems to keep pace with increasingly precise timelines of paleoenvironmental change during LIP emplacement.