4th International Conference of Palaeogeography

192 / 2019-06-13 12:55:26

High-precision dating links Early Permian climate optimum to large igneous province

North China, mudrocks, high-precision dating, paleoclimate, weathering trends

Tracking climate change and its relationships with chemical weathering and massive volcanic activity in deep-time greatly improves our understanding of the Earth`s climate system. High precision CA-TIMS U-Pb zircon ages for three tuffaceous layers from a cored upper Carboniferous-lower Permian marginal marine succession in southern North China accumulated between ~302–290 Ma, calibrating the Permo-Carboniferous biostratigraphy in North China. Weathering index values determined on screened mudrock samples constrain weathering trends for the source landscapes. Such trends, coinciding with the glacial records in high latitudes, marine-terrestrial temperature changes in low latitudes, relative sea-level variations, and atmospheric pCO2 reconstruction, document an earliest Permian climate optimum. This Permo-Carboniferous icehouse climate perturbation correlates with the emplacement of the Skagerrak-Centered (also named Skagerrak or Jutland) large igneous province. This igneous province likely released voluminous CO2 gas, leading to climate warming during the Permo-Carboniferous transition, and the associated basaltic rocks likely underwent rapid post-eruptional weathering in tropical latitudes, consuming atmospheric CO2 and thus responsible for the subsequent cooling.