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。     

Characteristics of soure region and tectonic implications of Early Indosinian Weiya gabbroic rock, eastern Tianshan mountains

Based on the detailed petrographic study, the characteristics of source region of the Weiya gabbro and tectonic implications were studied. The results show that the gabbroic rock consists mainly of gabbro, with less amount of ultra-mafic rocks. The ultra-mafic rocks show cumulate texture and are gradually transitional contact with gabbro, indicating that they are cumulate products of parental magma. The ultra-mafic rocks consist mainly of spinel periodite and spinel clinopyroxenite. The former is mainly composed of olivine （65%-70%）, spinel （10%-15%）, hornblende （5%-10%） and phlogopite （5%-10%）; the latter consists mainly of clinopyroxene （70%-80%）, spinel （15% 20%） and phlogopite （0-10%）, with minor amounts of carbonate （0-2%）. No olivine or orthopyroxene is found. The gabbro is composed mainly of clinopyroxene （35%-40%）, plagioclase （An 55-65, 40%-45%）, hornblende （5%-15%）, with variable amounts of carbonate （0-5%）. Petrographic observations show that the source region of the Weiya gabbroic rock is water-rich due to intensive intra-continental A-type subduction occurring in this region during late Permian to early Triassic.