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中文摘要：
随着精细年代学研究的发展，越来越多的证据表明地幔柱作用下的大火成岩省和地质历史时期的生物绝灭之间有着密切的联系。我国西南地区峨眉山溢流玄武岩省是目前我国惟一被国际认可的大火成岩省，为了更好地证明峨眉山大火成岩省与同期生物、环境变化之间的关系，选择贵州望谟乐康剖面石灰岩开展了碳同位素组成研究。结果表明，在峨眉山地幔柱作用之前的茅口阶碳同位素组成显示出较高的正值（δ^13C=5．2‰～4．0‰）；茅口阶顶部至领薅组第一段δ^13C值主要落在2‰～4‰范围内，其时序上对应于峨眉山玄武岩主喷发之前的区域穹状隆升时期；之后由于峨眉山大火成岩省有关的大规模火山作用导致低值碳源加入，当时缓慢复苏的生物作用造成的碳同位素组成增加远不能抵消火山作用造成的碳同位素组成降低，导致期间碳同位素组成明显降低（变化于0‰～2‰范围），并出现负漂移。该剖面碳同位素组成的变化为峨眉山地幔柱作用对生物和环境效应的研究提供了重要信息。
英文摘要：
More and more geochronological data show that large igneous province （LIP） coincide with the mass extinction event. At present, the late Permian Emeishan Flood Basalts province is commonly accepted as the large igneous province relative to mantle plume in China. In order to probe the environmental effect of the Emeishan LIP, the carbon isotopes of the marine carbonate rocks of the Lekang section in Wangmo County, Guizhou Province is performed. The results show that the evolution of δ^13C in this profile can be divided into three segments. The highly positive δ^13C （ δ^13C = 5.2‰ - 4.0‰ ） values during the Wuchiapingian suggest a mild climate and blooming of biomass. Before the eruption of the Emeishan flood basalts, the rapid crustal uplift was developed, which resulted in the regressing in the region. The extinction of biomass and the oxidation of the previously buried organism result in the drop of δ^13C values during regressing, and most of δ^13C values vary from 2%c to 4%c. After that, the intensive volcanic activity in the southwest of China associated with the Emeishan LIP cause the further decrease of the δ^13C values. The δ^13C values fluctuate between 0‰ and 2‰. That is because the recovery was very slow in the severe environment during the volcanic activity, and the volcanic can release the CO2, which is isotopically light. The enrichment of the carbon isotope of the organisms after extinction cannot counteract the carbon isotope drops from volcanic eruption. Carbon isotope patterns indicate important information on the environmental effect during the Emeishan LIP activity.
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