摘要
下扬子地区下古生界广泛分布富有机质海相泥页岩,是油气资源勘探远景区。下古生界海相页岩主要有2套重点目的层系,即下寒武统荷塘组/幕府山组、下志留统高家边组。为了查明下扬子下古生界页岩层系的页岩气潜力,对下寒武统、下志留统页岩的基本地质特征(页岩分布、脆性矿物、储集特征)及页岩气赋存条件进行分析,并分别针对这2套页岩层系发育有利区带进行综合评价。研究认为:①下古生界发育富有机质泥页岩,下寒武统泥页岩南北厚、中间薄,厚度在100m以上;下志留统仅在北部发育连续泥页岩,厚度在60m以上。②下寒武统南北泥页岩TOC大于3.0%,Ro大于3.0%;下志留统北部局部泥页岩TOC大于2%,其余地区丰度较低,Ro为2.0~3.0%。③分析认为下寒武统南北部和下志留统北部为下古生界页岩气有利勘探区。以上成果认识,对同类盆地古生界页岩层系页岩气潜力呈认识具有一定指导意义。
Organic marine mudstones are widely distributed in the Lower Paleozoic of the Lower Yangtze, which is a prospective area for oil and gas exploration. The marine shale in the Lower Paleozoic has two main strata, namely the Lower Cambrian Hetang formation/ Mufushan formation and the Lower Silurian Gaojiabian formation. In order to find out the shale gas potential of the Lower Paleozoic shale strata in the Lower Yangtze, the basic geological characteristics (shale distribution, brittle minerals, reservoir characteristics) and the occurrence conditions of shale gas of the Lower Cambrian and Lower Silurian shales were analyzed, and evaluated respectively the favorable zones for the development of these two shale strata. The results show that:①The organic shale is developed in the Lower Paleozoic, the Lower Cambrian shale is thick in the north area and the area south, and intermediate thin, with a thickness of more than 100 m, while the Lower Silurian shale is only developed in the north, with a thickness of more than 60 m.② TOC of the Lower Cambrian shale is more than 3.0%, R o is more than 3.0%. TOC is more than 2% in the northern part of Lower Silurian, and the organic matter abundance of other areas is lower, R o is 2.0%~3.0%.③Analysis shows that the north part and south part of the Lower Cambrian and the north part of the Lower Silurian are favorable exploration areas for the Lower Paleozoic shale gas. The above results are of guiding significance to the understanding of shale gas potential of the Paleozoic shale strata in similar basins.
作者
印燕铃
Yin Yanling(Exploration Development & Research Institute of SINOPEC East ChinaOil and Gas Company, Nanjing, Jiangsu 210011, China)
出处
《非常规油气》
2019年第3期26-32,共7页
Unconventional Oil & Gas
基金
国家科技重大专项项目“下扬子页岩气潜力分析与目标评价”(2017ZX05036003-009)资助
关键词
下扬子区
下古生界
页岩层系
the Lower Yangtze region
the lower Paleozoic
shale strata
