摘要
为进一步分析与探讨海陆交互相页岩的资源潜力,选取鄂尔多斯盆地东北部临兴地区太原组地层为研究对象,根据大量的岩芯、测井及地化资料,结合层序地层与沉积相的理论知识,对海陆交互相泥页岩的沉积环境和发育特征进行研究.通过野外露头、岩心观察和测井等资料,总结临兴地区太原组的沉积环境,并结合有机碳、镜质体反射率和岩石矿物含量的实验数据进行泥岩发育特征的分析,认为太原组地层主体发育障壁型海岸相沉积,泥页岩发育特征良好,且不同沉积环境下的泥岩有机碳含量存在差异性.研究结果表明:临兴地区太原组整体经历一个完整的长期旋回,并据此可划分为太1段(p1t^1)和太2段(p1t^2);太1段(p1t^1)主体发育潮坪相沉积体系,太2段(p1t^2)主体发育障壁岛-潟湖-潮坪的障壁型海岸沉积体系;泥页岩发育特征良好表现为太原组地层虽泥页岩发育的整体厚度变化较大,但累计厚度大于30 m的区域较为可观;太原组TOC均值为3.69%,太2段(p1t^2)的有机质含量略高于太1段(p1t^1);热演化程度较高,镜质体反射率(R0)均值1.39%;干酪根类型为Ⅲ型,以产气为主;岩石矿物组分中脆性矿物百分比较高,脆性指数普遍大于50%,可压性良好;根据不同的沉积环境将泥页岩划分为4种类型,其中沼泽相碳质泥岩的有机碳含量最高.综合评价认为,该地区太原组整体展示较好的页岩气勘探开发潜力,且不完全氧化的沉积环境更有利于有机质的发育.
For further analysis and discussion of the resource potential of marine-terrigenous interdepositional systems, the Taiyuan formation of Linxing area in the northeastern Ordos basin was chosen as the research object. According to a large amount of core, logging and geochemical data, and the theory of sequence stratigraphy and sedimentology, the sedimentary environment and characteristics of the marine-terrigenous interdepositional shale were obtained. Through the field outcrop, core observation and well logging data, the sedimentary environment of Taiyuan group in Linxing area was acquired. Combined with the experimental data of organic carbon, vitinite reflectance and rock mineral content, the characteristics of mudstone were analyzed. It is considered that the Taiyuan formation in Linxing area develops barrier coastal facies deposition, and the organic carbon content of mudstone in different sedimentary environments is different. The results show that the Taiyuan formation in Linxing area has experienced a complete long-term cycle, which can be divided into Tai1 formation(p1t^1) and Tai2 formation(p1t^2). Furthermore, the tidal flat facies are developed in Tai1 formation(p1t^1), and the barrier island-lagoon-tidal flat coastal sedimentary system are developed in Tai2 formation(p1t^2). In addition, the mud shale has better development characteristics. Although the thickness of the shale of Taiyuan formation varies greatly, the area with accumulated thickness greater than 30 m is large. The average organic carbon content in the Taiyuan group is 3.69%, and that content in the Tai2 formation(p1t^2) is slightly higher than that in the Tai1 formation(p1t^1). High level of thermal evolution is developed with the average vitrinite reflectance(R0) of 1.39%. The mud shale is kerogen type Ⅲ, which mainly develops gas. The brittle mineral content in the rock mineral components is higher, and the brittleness index is generally greater than 50%, which indicates a good compressibility. The mud shale can be divided into four
作者
薛纯琦
吴建光
钟建华
张守仁
张兵
郝兵
王丹玲
XUE Chunqi;WU Jianguang;ZHONG Jianhua;ZHANG Shouren;ZHANG Bing;HAO Bing;WANG Danling(School of Geosciences, China University of Petroleum (East China), Qingdao, Shangdong 266580, China;China United Coalbed Methane Company Limited, Beijing 100011, China;Perto China North China Oil Field Branch,Renqiu, Hebei 062552, China)
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2019年第4期870-881,共12页
Journal of China University of Mining & Technology
基金
国家科技重大专项(2016ZX05066001-003)
关键词
页岩气
海陆交互相
有机地化特征
沉积相
主控因素
shale gas
Marine-terrigenous facies
organic geochemical characteristics
sedimentary
controlling factors
