辽西牛营子凹陷中元古界推覆体以下发现早中侏罗世优质烃源岩新地层  

Discovery of the Jurassic strata of organic-rich source rocks under the Middle Proterozoic thrust-nappe in Niuyingzi depression, westhern Liaoning Province

作　　者：孙求实[1] 宗文明[1] 王斯佳 孙守亮[1] 李永飞[1] 郜晓勇[1] 张涛[1] SUN Qiushi;ZONG Wenming;WANG Sijia;SUN Shouliang;LI Yongfei;GAO Xiaoyong;ZHANG Tao(Shenyang Center of Geological Survey,China Geological Survey(CGS)/Northeast China Center for Geoscience Innovation,Shenyang 110034,Liaoning,China;Liaoning Geology and Mineral Construction Group CO.LTD,Shenyang 110013,Liaoning,China)

机构地区：[1]中国地质调查局沈阳地质调查中心(东北地质科技创新中心),辽宁沈阳100034 [2]辽宁地矿建设集团有限公司,辽宁沈阳110013

出　　处：《中国地质》2022年第4期1285-1294,共10页Geology in China

基　　金：中国地质调查局项目(DD20190098,DD20221664)资助。

摘　　要：【研究目的】一直以来辽西牛营子凹陷油气勘探的目的层为中新元古界。由于构造抬升等因素,该凹陷地表未见辽西其他盆地出露的重要油气勘探层系—侏罗系北票组。【研究方法】本次通过辽凌地1井钻探,在牛营子凹陷中元古界碳酸盐岩推覆体下发现了一套厚层暗色泥岩,对其岩性及孢粉组合特征进行研究,并与辽西北票盆地实测的三宝四坑剖面北票组进行岩性组合对比。【研究结果】证实辽凌地1井中元古界碳酸盐岩推覆体以下厚层泥岩为侏罗系北票组。【结论】有机地球化学指标表明,该泥岩具有有机质丰度高、生烃潜力大的特点,是值得关注的优质烃源岩。该套厚层暗色沉积地层的发现表明侏罗系北票组是牛营子凹陷新的勘探层系,这一认识为研究辽西地区构造演化、油气地质条件提供了重要的基础地质资料。[Objective] The target layer for oil and gas exploration in the Niuyingzi depression in western Liaoning Province has been MesoNeoproterozoic. Due to tectonic uplift and other factors, the Jurassic Beipiao Formation, which is an important hydrocarbon exploration target widely exposed in other basins in western Liaoning, is not found on the surface of this depression. [Methods]During the drilling of the LLD1 well, a set of thick dark mudstone layers were discovered beneath the Mesoproterozoic carbonates.Based on correlations of lithology and spore-pollen assemblages of the newly discovered mudstones with those from the Beipiao Formation in the Sanbaosikeng section of Beipiao Basin in western Liaoning Province. [Results] The layers discovered were from the Beipiao Formation.[Conclusions] Organic geochemical indexes indicate that the mudstone is of high organic matter abundance and high hydrocarbon generation potential. Hence, mudstones from Beipiao Formation in this area is a set of high-quality hydrocarbon source rock worthy of exploration. The discovery of thick dark organic-rich layers indicates that the Jurassic Beipiao Formation is a new target for oil and gas explorations in the Niuyingzi Depression. Moreover, this new discovery also provides important basic geological information for the study of tectonic evolution and hydrocarbon geological conditions in western Liaoning Province.

关 键 词：地层厘定 牛营子凹陷 北票组 早—中侏罗世 油气勘查工程 辽宁西部 

分 类 号：TE121.2[石油与天然气工程—油气勘探]