鄂尔多斯盆地西南缘印支期沉积特征及物源

目的研究鄂尔多斯盆地西南缘惠安堡-马家滩地区印支期河湖相砂岩沉积特征及物源区。方法采用地层层序及沉积格局、实测典型剖面、古流向测量及砂岩碎屑颗粒组成特征研究等综合方法研究。结果划分了印支期构造层序;编制了沉积厚度等值线图及岩相古地理图;编制了古流玫瑰花图;统计了碎屑颗粒组成特征,分析了物源区构造环境。结论研究区印支期构造层由3套构造亚层组成,属于大型河流-三角洲沉积体系,自西北向东南方向延伸,砂岩物源可能与阿拉善地块古元古界变质结晶岩、花岗岩及下古生界火山岩有关。

Sedimentary characteristics and provenance analysis of Indo-Chinese epoch in the southwest edge of Ordos Basin

Aim To study the Sedimentary characteristics and provenance region of indo-chinese epoch sandstone in Huianbu-Majiatan area , southwest edge of Ordos Basin. Methods With the assistance of the research of stratum sequence and sedimentary environment in the region , the typical section plane was investigated, the palaeoeur rent data in the field was collected, the component characteristics of clastic material were studied. Results Permi an-Triassic tectonic stratum sequence was studied. Sedimentary thickness isoline graph, litho facies paleogeography graph and paleocurrent rose graph were plotted. The clastic grain component characteristics were lucidated and provenance region tectonic environment was analysized. Conclusion The indo-chinese epoch stratum in the studied area contains three suites tectonic subordinate stratum, which mainly consists of fluvial and lacustrine facies clastic rock and spreads from northwest to southeast. The lower Proterozoia metamorphosized rock and granite and Lower Palaeozoic igneous rock from the northwest Alanshan Plane probably contribute to the provenance of the studied sandstone.