准噶尔盆地陆西地区石炭系火山岩有利区分析

通过对陆西地区石炭系火山岩岩性特征、岩相展布、构造演化过程、裂缝分布规律、已知含油气层分布区、岩性与油气层的关系、不同岩性岩相的物性特征、烃源条件等进行分析,认为陆西石炭系存在上、下两个层序,这两个层序的顶界均为区域性不整合面;火山岩相主要有火山通道相、爆发相、溢流相和火山沉积相等4种类型,不同层序相分布有所不同;陆梁隆起的雏形形成于中海西运动第一幕,晚海西期得到定型与加强;上层序物性最好的岩相是溢流相,其次是爆发相,物性最好的岩性是玄武岩,其次是火山角砾岩;有利储层分布区有两个,一个位于夏盐凸起东部的夏盐1—石南3井区,另一个位于夏盐凸起西部及三个泉凸起区;陆西地区的烃源主要来源于玛湖凹陷。最后指出陆西石炭系油气勘探的有利区主要位于夏盐凸起与三个泉凸起的西部。

Analysis of Carboniferous Favorable Place of Volcanic Rock in Luxi Area,Junggar Basin

Based on the analysis of Carboniferous igneous lithological character and its lithofacies distribution,structural evolutional process,fracture distribution law,known petroliferous and gas distribution area,relationship between lithological character and oil-gas formation,physical properties of different lithological character and lithofacies,conditions of hydrocarbon source. It is believed that in Carboniferous system where exist two sequences which are an upper sequence and a lower one at Luxi area of Junggar Basin,and the superfaces of these sequences are regional unconformities. There are mainly four kinds igneous lithofacies which are volcanic conduit facies,explosive rock facies,overflow facies,and volcanogenic sedimentation facies,which distribute among different sequences. The embryonic form of Luliang uplift began at stage I of Mid-Hercynian phase,and formed and strengthened at late-Hercynian phase. The best physical properties of lithofacies is the overflow facies, the second one is explosive rock facies. The best physical properties of lithological character is basalt,the second one is volcanic breccia. There are two favorable reservoir areas in Luxi,one locates at Xiayan 1 to Shinan 3 of the East Xiayan salient,and the other one located at the West Xiayan salient and Sangequan salient. Hydrocarbon of Luxi came mainly from Mahu sag. This paper presents that the oil and gas favorable places for prospecting mainly located at west areas of Xiayan salien and Sangequan salient.