| Abstract: |
The Emeishan flood volcanism that erupted at Permian-Triassic boundary time produced a large igneous province of at least 2.5 X 10^5 km² in the western margin of the Yangtze craton, southwestern China. The volcanic successions, suggested to have resulted from a starting mantle plume, comprise thick piles of basaltic flows and subordinate picrites and pyroclastics. The picrites, which have high magnesian contents (MgO ≊ 2016 wt%), variable degrees of light rare earth element enrichment [(Ce/Yb)<sub>N</sub> ≊ 425] and heterogeneous isotope ratios [ϵ<sub>Nd</sub> ≊ (T) +4 to −4], are proposed to have been generated by mixing between the dominant plume-derived magmas and small amounts of lamproitic liquids from the continental lithospheric mantle.
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