银额盆地哈日凹陷Y井油气地球化学特征与油气源对比

Y井是银额盆地哈日凹陷施钻的第一口揭示二叠系厚度较大的参数钻井,于二叠系试获天然气9.15×104m3/d(无阻流量),并产少量凝析油。在对Y井天然气及凝析油组分、同位素,以及凝析油生物标志化合物等分析的基础上,探讨了天然气和凝析油成因类型。结果表明,天然气为油型(腐泥型)凝析油伴生气,凝析油为高成熟腐泥型,生烃母质以水生生物为主,烃源岩演化进入高成熟阶段。将Y井凝析油与哈日凹陷周缘杭乌拉剖面出露的下二叠统埋汗哈达组烃源岩生物标志化合物特征进行对比,二者具有良好的亲缘关系,Y井凝析油及天然气源于二叠系,进一步证实了银额盆地石炭系—二叠系良好的油气资源前景。

Geochemical characteristics and oil-source correlation of Well Y in Hari depression, Yingen-Ejin basin

Well Yin in the Hari depression is the first parameter well which reveals thickness of Permian strata. Additionally, the open flow capacity of this well reaches 91500m³ natural gas per day together with a little condensate oil. Based on the component and isotope analysis of natural gas and condensate oil biomarkers, this paper discusses the original type of natural gas and condensate oil of Well Y. The result shows that the natural gas is saprogelic type-associated gas, whereas the condensate oil is high maturity sapropelic oil. The parent material of raw hydrocarbon is dominated by aquatic organisms. The evolution of source rocks gets into high maturity stage. It shows well affinity correlation with hydrocarbon source rock of the lower Permian Maihanhada Formation in Hangwula profile, Hari depression. Apparently, the condense oil and natural gas of Well Y was derived from the Permian strata. Additionally, it is verified that the Carboniferous-Permian strata has good hydrocarbon prospects in Yingen-Ejin basin.