重庆秀山寒武纪海相碳酸盐的锶同位素组成及其地层学意义STRONTIUM ISOTOPE COMPOSITION OF THE CAMBRIAN LUOJIAGUO SECTION IN XIUSHAN, CHONGQING AND ITS STRATIGRAPHIC SIGNIFICANCE
石和,黄思静,沈立成,张萌
摘要(Abstract):
锶同位素地层学是化学地层学的组成部分 ,简要介绍重庆市秀山县溶溪乡罗家沟寒武系剖面海相碳酸盐的锶同位素分析结果 ,建立了该剖面的锶同位素演化曲线 ,并与 Gao及 Denison等的同期锶演化曲线作了对比 ,秀山寒武纪锶同位素演化曲线与其他两条同期曲线有较大相似性 ,据此提出了秀山寒武系剖面部分主要年代地层界线的参考意见 ,并简述了寒武纪全球海平面变化的概况。
关键词(KeyWords): 秀山;四川;寒武系;锶同位素演化曲线;年代地层;对比;化学地层学
基金项目(Foundation): 国家自然科学基金项目“上扬子古生代海相碳酸盐的锶同位素组成及主要控制因素”(批准号 :No.49972 0 44)资助。
作者(Author): 石和,黄思静,沈立成,张萌
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