特种油气藏2023，Vol.30Issue(6)：55-61,7.DOI:10.3969/j.issn.1006-6535.2023.06.008
松辽盆地南部长岭断陷青一段陆相页岩地球化学和沉积环境特征
Characteristics of Geochemistry and Depositional Environment of Terrestrial Shales in the First Member of Qingshankou Formation of Changling Fault Depression in the Southern Songliao Basin
摘要
Abstract
In response to the problem of unclear understanding of geochemistry and depositional environment charac-teristics of terrestrial shale in the first member of Qingshankou Formation of Changling fault depression in the south-ern Songliao Basin,the experiments on organic geochemistry,molecular geochemistry and elemental geochemistry were systematically carried out to clarify the hydrocarbon generation potential of terrestrial shale in the study area,and to explore the controlling effect of depositional environment characteristics on the enrichment of organic matters.The study results show that the terrestrial shale in the first member of Qingshankou Formation is rich in organic mat-ters,with an average TOC of 1.71％and an average chloroform asphalt"A"of 0.52％,which has good hydrocar-bon generation potential.The types of kerogen are mainly Ⅰ and Ⅱ 1,and the thermal evolution of organic matter is at a mature stage,with the average pyrolysis parameter Tmax of 447 ℃ and average Ro of 1.06％;the C27-C29 regular sterane indicates that the organic matter of the shale is mainly originated from lower-order aquatic organ-isms,such as algae,and partly imported from higher-order plants,the ratio of trace elements and biomarker com-pound parameters indicate that the paleoproductivity level is high,and the shale is originated from saline-water and brackish-water reducing environment,which is favorable for organic matter preservation;the chloroform asphalt"A"has a positive correlation with P/Ti and Sr/Ba,which suggests that the paleoproductivity and the preservation conditions jointly control the organic matter enrichment of shale.According to the evaluation criteria of shale oil"sweet spot"of TOC＞2.00％and S1＞1 mg/g,the favorable area is determined to be 5 000 km2,and the geological reserves calculated by volumetric method is 54.7x108t.The study is of strategic significance for the evaluation of shale oil resource potential in the southern Songliao Basin.关键词
地球化学/沉积环境/陆相页岩油/青一段/长岭断陷/松辽盆地Key words
geochemistry/depositional environment/terrestrial shale oil/first member of Qingshankou Formation/Changling Fault Depression/Songliao Basin分类
石油、天然气工程引用本文复制引用
赵晨旭,李忠诚,郭世超,鲍志东,魏兆胜,李磊,王海龙..松辽盆地南部长岭断陷青一段陆相页岩地球化学和沉积环境特征[J].特种油气藏,2023,30(6):55-61,7.基金项目
中国石油前瞻性基础性项目"松辽盆地深部含油气系统研究"(2021DJ0205) （2021DJ0205）
