鄂尔多斯盆地甘泉西部延长组下组合烃源岩生物标记化合物特征研究
打开文本图片集
中图分类号：P618.13 文献标识码：A 文章编号：2097-5465（2026）02-0048-10
Abstract：ToclarifythegeologicalgenesisandevolutioncharacteriticsoftheLowerMemberoftheYanchangFormationsource rocksinthe westernpartof Ganquan，Ordos Basin，thispaper，basedonthetectonicbackgroundof thesouthernpartof the northern slopeof Shanxi Province，combined with theTriasiclatelakebasin expansionandregresionsedimentarysequence， systematicallanalyedtedistributioncharacteristicsofbiomarkercompoundssuchasn-alkanes，terpenoids，andsteransthough techniquessuchasgaschromatogaphymaspectrometrykerogemicroscopyandelementalanalysis.Thestudyalsocoelatedthe sedimentaryfaciesevolution，sourcesuply，andegionalhydrocarbonaccumulationpaers，，evealingthegeologicalsigniicance ofthesourcerocksintermsoforganic matersources，sedimentaryenvironments，and thermal evolution，andestablishedthe" source-reservoir-cap"hydrocarbonaccumulationconfigurationrelationship.Theresultsshowthattheorganicmattertypeof the source rocksin the study areais TypeIand Type II1 ，withhigh organic carboncontent（TOC），reaching the standard of highquality source rocks；the Pr/Phratio （0.59～1.43），V/（V + Ni）ratio （average O.78），and horizontal bedding sedimentary structures jointlyindicateaweaklyreducing-weaklyoxidizing，deeplake-semi-deeplakesedimentaryenvironment，andthe reduction degree is the highest in the Chang 73 sub-member （the maximum lake transgression period）；the organic matter sources havemixedcharacteristics：mainlylow-gradeplanktonicorganisms，andpartlyfrom higherorganisms；thesourcerockshavegenerally entered the mature stage （ Ro=0.87%～1.26% ），at the peak of hydrocarbon accumulation，and form a "self-generationself-storage -upper generation-lower storage"hydrocarbon accumulation model with the Chang 8～ Chang 9 tight sandstone reservoirs，and lithologic traps and fracture development areasare favorable exploration directions.
eywords：biomarker compounds；Ordos Basin；source rocks；sedimentary environment；organic matter typ
0 引言
鄂尔多斯盆地作为中国中生代陆相含油气盆地的典型代表，长期以来，学界对延长组烃源岩的研究多聚焦于岩石学特征、测井响应、分布范围及宏观有机地球化学分析，而针对延长组下部长7～长9油层组烃源岩的生物标志物精细研究相对薄弱，尤其缺乏对该区域特定构造背景与沉积序列下，生物标志物与有机质来源、沉积环境的关系分析研究。（剩余9171字）