大别山东南缘侏罗系磨山组沉积环境及地质意义

发布时间：2018-04-26 07:42

本文选题：侏罗纪 + 大别造山带　；参考：《岩石学报》2017年02期

【摘要】：侏罗纪是大别造山带与周缘盆地盆山关系研究的一个重要时期,分布在大别造山带周缘的侏罗纪地层为大别山的造山过程以及深俯冲岩石的折返、剥蚀提供了很好的约束。本文选取大别造山带东南缘安庆月山地区侏罗系磨山组为研究对象,对磨山组碎屑岩进行了详细的粒度分析、碎屑组分分析、重矿物分析和碎屑锆石年代学分析。碎屑岩岩石、沉积特征和粒度分析都指示早侏罗世磨山组为三角洲前缘水下分流河道沉积。碎屑组分分析、重矿物分析结合碎屑锆石年代学分析指示磨山组碎屑岩物源主要来自南侧的华南板块,大别造山带宿松杂岩可能为其提供了少量物源,但碎屑物源中未见石榴子石和典型的三叠纪变质锆石,说明此时大别高压-超高压榴辉岩可能仍未折返至地表。
[Abstract]:Jurassic is an important period in the study of the relationship between the Dabie orogenic belt and the basin. The Jurassic strata distributed around the Dabie orogenic belt provide a good constraint for the orogenic process of the Dabie Mountains and the exhumation and erosion of the deep subduction rocks. In this paper, the Mushan formation of Jurassic system in Anqing Yueshan area, southeast margin of Dabie orogenic belt, is selected as the research object. Detailed grain size analysis, clastic component analysis, heavy mineral analysis and zircon chronology analysis of the Moshan formation are carried out. The sedimentary characteristics and grain size analysis of clastic rocks indicate that the early Jurassic Moshan formation is a delta front subaqueous distributary channel deposit. The clastic composition analysis, heavy mineral analysis and zircon chronology analysis indicate that the source of clastic rocks of the Moshan formation mainly comes from the South China plate in the south, and the Susong complex in the Dabie orogenic belt may provide a small amount of provenance. However, no pomegranate and typical Triassic metamorphic zircon were found in the clastic provenance, indicating that the Dabie high-ultrahigh pressure eclogite may not return to the surface at this time.
【作者单位】：合肥工业大学资源与环境工程学院;
【基金】：国家自然科学基金项目(41272222) 安徽省自然科学基金项目(JZ2015AKZR0627)联合资助
【分类号】：P534.52

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