中国地质Issue(5)：1682-1692,11.
四川盆地东南缘中上寒武统白云岩地球化学特征及成因机制
The characteristics and genetic mechanism of middle-upper Cambrian dolomite on the southeast margin of Sichuan Basin
摘要
Abstract
Based on petrological and geochemical analysis of middle-upper Cambrian dolomite in three different profiles, the authors hold that the dolomite was mainly formed by brine reflux dolomitization in the early bury period, together with mixing water replacement. The evidence obtained is as follows:①the ratios of Sr/Ba in dolomite and calcite are high, with only a few data being lower than 1;②the values of Na and K are high in calcite, the content of Na in calcite is higher than that of middle Ordovician Mifflm Member calcite in Wisconsin and that of upper-Ordovician calcite in Tongling of eastern Tennessee characterized by fresh water origin, and the content of Na in dolomite is equal to that of Sabkha dolomite in Barbwire terrace of Canning basin; ③ the values of m suggest that the calcite was in a seawater sedimentary environment, and the dolomite was in a lagoon sedimentary environment;④the values of revised B show that the calcite and dolomite were formed in salt and semi-salt water, partly affected by fresh water. The Sr values were impoverished during the dolomitization, and Na and K might also have been impoverished in this process.关键词
白云岩/地球化学/渗透回流/混合水Key words
dolomite/geochemistry/brine reflux/mixed water分类
天文与地球科学引用本文复制引用
刘建清,赵瞻,林家善,冯伟明,黄学平,魏洪刚..四川盆地东南缘中上寒武统白云岩地球化学特征及成因机制[J].中国地质,2014,(5):1682-1692,11.基金项目
成都理工大学“油气藏地质及开发工程”国家重点实验室开放研究基金（PLC200901）资助。 （）
