Plume-induced emissions of deep methane linked to the end-Guadalupian mass extinction

Methane (CH₄) is a potent greenhouse gas, and massive CH₄ emissions have the capacity to cause rapid and catastrophic climate effects. Here we report findings of large amounts of CH₄ occurring as an important vapor phase in melt inclusions trapped by magmas in the plume-related Permian Emeishan large igneous province (LIP). Lines of evidence indicate that the CH₄ is dominantly abiogenic and primarily had a mantle origin. Undegassed magmas are estimated to contain ~ 0.03% (by weight) CH₄, which coincides with the relatively low oxygen fugacities of primary Emeishan LIP magmas. Our findings demonstrate that abiogenic CH₄ can be generated in the mantle sources of a plume-related LIP, and that such CH₄ could be brought into the surface by LIP magmatism and lead to strong warming. Quantitative models suggest that release of magmatic CH₄ in the Emeishan LIP (7.4 × 10³ Gt) had a significant contribution to the end-Guadalupian mass extinction.