萍乐坳陷中二叠统小江边组岩相古地理及烃源岩研究

发布时间：2018-03-18 09:10

  本文选题：萍乐坳陷　切入点：小江边组　出处：《成都理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：在利用前人研究成果的基础上,结合野外露头、区调资料,对研究区的区域构造进行总结和分析,然后利用沉积岩石学、岩相古地理学等理论研究了萍乐坳陷中二叠统小江边组的沉积相类型和岩相古地理特征,结合烃源岩的平面特征和有机地化特征,进行油气远景分析。萍乐坳陷中二叠统小江边组为一套灰黑色钙质页岩及碳质页岩夹灰岩透镜体沉积,中二叠世晚期,海平面快速上升,海水加深明显,研究区内主要发育混积陆棚相,进一步可以分为浅水内陆棚和深水外陆棚亚相以及陆棚泥和灰泥丘微相。研究区内小江边组的烃源岩以暗色泥页岩为主,其分布在平面上具有相当规模的展布,占地层比例的变化范围为64.72%-81.77%。有机地球化学的实验表明,研究区小江边组的有机碳含量普遍达到烃源岩下限,部分达到中等烃源岩标准,多数达到好的烃源岩标准,有机质类型以生气Ⅲ型为主,次为生油Ⅱ型。对烃源岩的热演化程度的研究显示,研究区内小江边组烃源岩的成熟度主要处于高成熟晚期阶段,部分达到过成熟阶段。研究区小江边组地层的生烃坳陷主要为西南部的萍乡、宜春、万载一带的深水外陆棚沉积,该区域的有机质丰度和有机质成熟度都较为理想,是良好的烃源岩潜力区。此外,萍乐坳陷中二叠统小江边组的非常规油气,特别是页岩气的资源潜力较好,有利区主要集中在清江盆地、锦江盆地和南鄱阳坳陷,这些地区同样也是重要的油气远景区。
[Abstract]:On the basis of previous research results, combined with field outcrop and regional data, the regional structure of the study area is summarized and analyzed, and then sedimentary petrology is used. The sedimentary facies types and lithofacies paleogeographic characteristics of the Xiaojiangbian formation of the Middle Permian in Pingle Depression are studied in the theory of lithofacies and paleogeography, combining with the plane and organic geochemistry characteristics of the source rocks. The Middle Permian Xiaojiang Bian formation in Pingle depression is a set of gray-black calcareous shale and carbonaceous shale intercalated limestone lens deposits. In the late Middle Permian, sea level rises rapidly and the sea water deepens obviously. There are mainly mixed continental shelf facies in the study area, which can be further divided into shallow water inland shelf and deep water outer shelf subfacies, shelf mud and plaster hilly facies. The hydrocarbon source rocks of Xiaojiang Bian formation in the study area are mainly dark mud shale. The distribution of organic carbon in the small Jiangbian formation in the study area is generally up to the lower limit of the source rock, and some of the organic carbon content of the Xiaojiangbian formation reaches the standard of the medium source rock, and the variation range of the proportion of the area covers a range of 64.72 and 81.77. Most of them meet the standard of hydrocarbon source rock, the organic matter type is mainly type 鈪，

本文编号：1628924