鄂尔多斯盆地杏子川油田延长组原油地球化学特征与油源探讨

陕北斜坡中部杏子川油田延长组原油物性、族组成、饱和烃气相色谱、萜甾烷生物标志化合物以及地质综合分析显示，不同层位延长组原油地球化学特征具有显著的差异。长4+5、长6原油性质基本一致，具有同源属性，其差异性可能主要与运移分馏效应以及原油成熟度有关。长9、长10原油与长4+5、长6原油性质具有明显的差异，反映了其具有不同的母源属性。Ts/Tm、C₂₉ββ/（ββ+αα）、αααC₂₉20S/（20S+20R）等反映原油成熟度的生物标志化合物显示长9、长10原油具有较高的成熟度。长9和长10原油规则甾烷含量显示具有不同的成因。地质综合分析和油源对比表明:长4+5、长6原油均来自于长7生油岩，长9原油来自于其顶部的李家畔页岩，长10原油可能主要来源于长92有效烃源岩。 

Geochemical characteristics of crude oil and oil-source correlation in Yanchang Formation in Xingzichuan Oilfield, Ordos Basin

There are significant differences between the crude oil in different horizons of Yanchang Formation, as is shown by the property, group composition, gas chromatography of saturated hydrocarbon, biomarker of terpane and sterane, comprehensive geological analyses. The crude oil properties of Chang-4+5 and Chang-6 are generally consistent and isogenous, whose difference may be related to migration fractionation effect and crude oil maturity. However, there exist obvious variances in the crude oil property between Chang-9 or Chang-10 and Chang-4+5 or Chang-6, indicating different maternal properties. The crude oils in Chang-9 and Chang-10 have relatively higher maturity, mirrored by the biomarkers of Ts/ Tm, C₂₉ββ / (ββ+αα) and αααC₂₉20S / (20S+20R), etc. The content of regular sterane in the crude oils in Chang-9 and Chang-10 shows different genesis. Thus, the comprehensive geological analyses and oil-source correlation manifest that the crude oils in Chang-4+5 and Chang 6 come from the source rocks of Chang-7, while the crude oils in Chang-9 generate from the Lijiapan shale, and the crude oils in Chang-10 may stem from the effective source rocks of Chang-92.