准噶尔盆地Z-1井油源分析

Z-1井位于准噶尔盆地昌吉凹陷、马桥凸起和中拐凸起3个二级构造单元结合部位,两个含油层段分别位于K₁tg4788—4797m和J₁$s^{1}_{2}$4 808.5—4812.5m.两层原油的族组分、全油碳同位素、饱和烃色谱和饱和烃色谱-质谱(GC-MS)分析结果表明,两层原油的族组分、碳同位素、各类生物标志物的地球化学特征基本一致,并且显示原油均主要源自成熟度较高的还原、含盐、富藻类湖相沉积岩系。油源分析认为,两层油主要源自二叠系烃源岩,并有侏罗系烃源岩或侏罗系和三叠系烃源岩原油的混入,这与区内存在多套烃源岩的地质背景吻合。

Analysis of Oil Source in Well Z-1 in Junggar Basin

Well Z-1 is located at joint among Changji sag,Maqiao swell and Zhongguai swell that are regarded as Grade-2 structural units in Junggar basin,in which two oil-bearing zones are found at 4 788-4 797 m(K1tg) and 4 808.5-4 812.5 m(J1s21).The GC-MS analyses indicate that both of them have generally consistent geochemical properties in crude family component,carbon isotope and biomarkers,and the same oil source from reducing,salt-bearing and algae-enriched lake facies sediments with high maturity.Oil-source correlation shows that the crude oils in two zones mainly originate in the source rocks of Permian,mixed with certain crude oils from Jurassic or Jurassic-Triassic source rocks.Such a result is consistent with the geological background of existing multi-set source rocks in the studied area.