摘要
依托南黄海盆地科学钻探CSDP-2全取心井岩心资料及其45块烃源岩样品的地球化学分析数据和12块含烃流体包裹体薄片的测温结果,在总结南黄海盆地烃源岩地球化学特征的基础上详细对比了其与上、中、下扬子板块烃源岩品质的异同并分析了其成因,进而结合油气显示和充注特征探讨了南黄海盆地上古生界—中生界的油气勘探前景。结果表明,CSDP-2井上古生界—中生界发育青龙组、龙潭组—大隆组和栖霞组3套区域性烃源岩层。其中,龙潭组—大隆组的有机质丰度以中—好为主且不乏优质烃源岩存在,其生、排烃强度最高达7.95×10~6t/km^2和1.65×10~6t/km^2;栖霞组烃源岩非均质性较强,碳质泥岩和臭灰岩的成烃演化基本处于成熟—高成熟阶段,生、排烃强度分别为6.52×10~6t/km^2和8.61×10~5t/km^2;青龙组泥质灰岩的生烃能力较弱,有机质丰度集中在中—差级别,排烃强度仅为1.27×10~5t/km^2。在沉积环境、有机质母源和生物生产率的共同影响下,南黄海盆地整体烃源岩品质与下扬子板块苏北盆地相当,但较上扬子板块四川盆地略差。同时,研究区海相地层经历了3期油气充注且已在CSDP-2井发现多处直接油气显示和气测高值异常,彰显了较为广阔的油气勘探前景。
Using the core data of Well CSDP-2 in the South Yellow Sea Basin,the geochemical data of 45 source rock samples and the temperature measurement results of 12 hydrocarbon-bearing fluid inclusion thin-sections,the geochemical characteristics of source rocks in the South Yellow Sea Basin are summarized in this study.On this basis,above source rocks and those in Upper,Middle and Lower Yangtze Blocks are compared in terms of the difference and similarity in quality,and the genesis of the former is also analyzed.Further,in combination with the characteristics of hydrocarbon indication and charging,this paper discusses the hydrocarbon exploration prospect of Upper Paleozoic and Mesozoic strata in the South Yellow Sea Basin.The results show that a total of three sets of regional source rocks,i.e.,Qinglong Formation,Longtan-Dalong Formation and Qixia Formation,distribute in the Upper Paleozoic and Mesozoic strata of Well CSDP-2.In the vertical direction,the organic matter abundance in the Longtan-Dalong Formation is dominated by"medium-good"quality and there is no lack of high-quality source rocks;the maximum hydrocarbon generation and expulsion intensities are 7.95×10~6 t/km^2 and 1.65×10~6 t/km^2,respectively.Source rocks in the Qixia Formation are strongly heterogeneous,where the hydrocarbon evolution of carbonaceous mudstone and swinestone is basically at the mature-high mature stage;the intensities of hydrocarbon generation and expulsion are 6.52×10~6 t/km^2 and8.61×10~5 t/km^2,respectively.The argillaceous limestone in Qinglong Formation shows poor hydrocarbon generation capacity,with the medium-low organic matter abundance and the hydrocarbon expulsion capacity of only about 1.27×10~5 t/km^2.Under the combined influence of sedimentary environment,organic matter parent source and biological productivity,the source-rock quality in the South Yellow Sea Basin is basically similar to that of Subei Basin located in the Lower Yangtze Block,but slightly inferior to that of Sichuan Basin located in the Upper Yangtze Block.Meanwhile,the marine strata in the South Yellow Sea Basin has experienced three periods of hydrocarbon charging;multiple direct hydrocarbon indications and high-value abnormalities of gas logging have been found in Well CSDP-2,showing a broad prospect for hydrocarbon exploration.
出处
《石油学报》
EI
CAS
CSCD
北大核心
2018年第6期660-673,共14页
Acta Petrolei Sinica
基金
国家海洋地质专项(DD20160147)
国家自然科学基金青年科学基金项目(No.41776081,No.41210005)
青岛市应用基础研究项目(2016239)
刘宝珺地学青年科学基金项目(DMSM2017025)资助
关键词
烃源岩评价
油气充注期次
勘探前景
上古生界—中生界
CSDP-2井
南黄海盆地
evaluation of hydrocarbon source rocks
hydrocarbon charging period
exploration prospect
Upper Paleozoic and Mesozoic
Well CSDP-2
South Yellow Sea Basin