Keywords:Sr isotope, Permian, carbonate
Stable strontium isotope ratios (δ88Sr) of the Capitanian (late Guadalupian) to Wuchiapingian (early Lopingian) carbonates were measured by TIMS, by correcting isotope fractionation during mass spectrometry with 87Sr-84Sr double spike. The studied carbonate section at Akasaka (Japan) in the Jurassic accretionary complex was originally deposited on a mid-Panthalassan paleo-seamount, which recorded a unique interval with extremely low 87Sr/86Sr values (the Permian minimum for ca. 5 m.y. throughout the entire Capitanian). We also analyzed the Wuchiapingian section at Lianshan in S. China, which was deposited on the shallow shelf. Both in δ88Sr and radiogenic 87Sr/86Sr ratios, low values remained throughout the Guadalupian, whereas they increased rapidly in the Wujiapingian. The newly obtained δ88Sr profile of Middle-Late Permian seawater positively correlated with that of 87Sr/86Sr ratio. As seawater δ88Sr could sensitively reflect marine carbonate flux at the ocean floor, this correlation suggests that the valance between the Sr carbonate burial flux and Sr carbonate dissolution flux has changed sharply across the Guadalupian-Lopingian boundary. The Capitanian minimum and the following rapid increase in seawater 87Sr/86Sr likely reflected a major change in continental flux, probably reflecting the rapid deglaciation together with enhanced erosion/weathering of continental crusts on a global scale.