古地理学报2012，Vol.14Issue(6)：747-756,10.
塔里木盆地东部地区寒武系白云岩成因类型
Genetic types of dolostones in the Cambrian, eastern Tarim Basin
摘要
Abstract
The types of dolostones in the Cambrian in eastern Tarim Basin include mud-sized to silt-sized crystalline dolostone, fine crystalline dolostone and medium-coarse crystalline dolostone. Based on sedimentary characteristics, order degree analysis , carbon and oxygen isotope analysis, strontium isotope analysis, cathodoluminescence and trace elements analysis, four dolomitization mechanisms were proposed for these dolostones, that is, deep water reflux penecontemporaneous dolomitization, evaporative pumping penecontemporaneous dolomitization, reflux seepage dolomitization, and burial dolomitization. Dolostones by different dolomitization mechanisms show different lithological and geochemical characteristics. Deep water reflux penecontemporaneous dolostone is mud-sized to silt-sized crystalline dolostone and occurs in eastern Tarim Basin. It results from penecontemporaneous dolomitization of lime mud by hypers-aline sea water, which forms on the adjacent evaporative Tarim Carbonate Platform and flows into the deep eastern Tarim Basin along sea floor. Evaporative pumping dolostone is mud-sized to silt-sized crystalline dolostone and occurs on the carbonate rock platform. It forms in the tidal-flat environments. Reflux seepage dolostone is fine crystalline dolostone and commonly occurs beneath evaporative pumping dolostone and evaporites on the carbonate rock platform. Burial dolostone is medium-coarse crystalline dolostone. It results from dolomitization of limestone in deep burial environments by cyclic formation water rich in Mg2+ and Ca +. Mg + and Ca + come from the dissolution of previous dolostones, rather than from compaction of shales.关键词
塔里木盆地东部地区/寒武系/深水回流准同生白云岩/蒸发泵准同生白云岩/回流渗透白云岩/深埋藏白云岩Key words
eastern Tarim Basin/Cambrian/deep water reflux penecontemporaneous dolostone/evaporative pumping penecontemporaneous dolostone/reflux seepage dolostone/burial dolostone分类
天文与地球科学引用本文复制引用
金振奎,杨有星,余宽宏,王哲,董晨晨..塔里木盆地东部地区寒武系白云岩成因类型[J].古地理学报,2012,14(6):747-756,10.基金项目
国家重点基础研究发展规划(973)项目(编号:2006CB202300)资助 （973）
