萍乐坳陷上二叠统乐平组富有机质页岩研究

发布时间：2018-06-26 17:16

  本文选题：萍乐坳陷 + 乐平组　； 参考：《成都理工大学》2017年硕士论文

【摘要】：本文以萍乐坳陷乐平组富有机质页岩为研究对象,选取野外典型露头剖面进行测量、描述、取样,并通过薄片鉴定分析、X-射线衍射全岩分析,以及总有机碳含量、热解、氯仿沥青“A”、干酪根碳同位素、镜质体反射率等有机地球化学分析,结合对前人相关地质资料的收集分析,系统研究了乐平组富有机质页岩的岩石类型、展布发育特征、沉积相、烃源岩特征、储层特征等页岩气资源条件。研究区乐平期受周期性海水作用,沉积了砂岩、炭质泥页岩、粉砂质泥岩、泥岩等,泥页岩主要分布于丰城地区及乐平地区,个别地区古植物发育形成含煤沼泽沉积,可见交错层理及泥质透镜状层理,总体为一套潮坪相含煤碎屑岩沉积。通过有机地球化学测试分析表明,研究区内乐平组富有机质页岩有机质含量总体较高,属于较好的烃源岩,萍乡一带有机质含量最高。有机显微组分及干酪根碳同位素分析表明,乐平组有机质母质为以陆生高等植物为主的腐殖型烃源岩,有机质类型以Ⅲ型为主,次为Ⅱ型。有机质成熟度测试分析表明,镜质体反射率较高,大部分样品达到高成熟阶段,部分为过成熟阶段,属产干气阶段。富有机质页岩以粘土矿物、石英为主,可见少量长石和方解石,高含量的脆性矿物显示泥页岩具有较好的脆性。富有机质页岩物性显示分析,页岩主要发育有机质孔、粒间孔和溶蚀孔,平均孔隙度和渗透率均较低。综合研究岩石学特征、沉积相、有机地球化学特征、物性特征及含气性分析后,认为研究区乐平组页岩气成藏属于潮坪相有机质高演化较低丰度富集模式,并优选乐平地区、萍乡-宜春地区为有利区。
[Abstract]:In this paper, the organic shale of Leping formation in Pingle depression is taken as the research object. The typical outcrop profile in the field is selected for measurement, description, sampling, and the whole rock analysis by X ray diffraction, total organic carbon content and pyrolysis are analyzed by thin slice identification. The organic geochemical analysis of chloroform bitumen "A", kerogen carbon isotope, vitrinite reflectance and other organic geochemistry analysis, combined with the collection and analysis of previous relevant geological data, systematically studied the rock types, distribution and development characteristics of organic shale rich in organic matter in the Leping formation. Sedimentary facies, source rock characteristics, reservoir characteristics and other shale gas resource conditions. During the Leping period, sandstone, carbonaceous shale, silty mudstone and mudstone were deposited in Leping period. The shale mainly distributed in Fengcheng area and Leping area, and some paleoplants developed to form coal-bearing swamp deposits. It can be seen that interlaced bedding and muddy lenticular bedding are a set of tidal flat coal clastic deposits. The organic geochemical analysis shows that the organic matter content of the organic shale of Leping formation in the study area is relatively high and belongs to the better source rock, and the content of organic matter in Pingxiang area is the highest. The analysis of organic macerals and kerogen carbon isotopes shows that the parent material of the organic matter of Leping formation is humic source rock with terrestrial higher plants, the type of organic matter is mainly type 鈪，

本文编号：2070789