准噶尔盆地中拐凸起上二叠统佳木河组火山岩油气成藏演化

Evolution of Volcanic Hydrocarbon Reservoirs of the Upper Permain Jiamuhe Formation in Zhongguai Uplift,Junggar Basin

准噶尔盆地中拐凸起上二叠统佳木河组油气藏属于自生自储型火山岩油气藏,其成藏关键在于构造、岩相、油源、圈闭及储盖等条件的时空匹配。通过钻井资料、测井解释、古地貌恢复技术、相干技术等地球物理方法剖析了研究区佳木河组油气藏的成藏演化过程。结果表明:火山作用控制了火山岩储集体的规模、岩性岩相及储层的储集性能,同时巨厚的火山岩加速了佳木河组有机质的成烃作用;中拐凸起东环斜坡区发育推覆型条带状"断凸"构造,顶部经风化淋滤作用和后期构造影响,形成溶蚀孔和裂缝发育的优质储层,与其上覆的风化黏土岩组成有利的储盖组合;推覆体中断裂相互交切,发育断层遮挡圈闭,形成南北向油气富集带。

To the formation of volcanic hydrocarbon reservoirs of the Upper Permain Jiamuhe Formation in Zhongguai uplift of Junggar Basin,the key is the spatial temporal matching relation of tectonic characteristics,lithology,hydrocarbon origin,trap,and sourcereservoircap assemblage.The evolution of volcanic hydrocarbon reservoirs of the upper Permain Jiamuhe Formation in the studied was comprehensively analyzed based on drilling data,logging interpretation,palaeogeomorphologic reconstruction,and seismic coherence technique.The results show that volcanism controls the scale,lithologic lithofacies and physical property of the reservoirs in the study area,and the thick volcanic rock accelerated the generation of hydrocarbon in the Jiamuhe Formation.A"faultconvex"structure showing a pattern of banded nappe was developed in the eastern slope of Zhongguai uplift.Affected by longterm weathering and post tectonic movements,the favorable reservoirs with dissolution pores and fractures were formed in the higher position of banded nappe"faultconvex"paleogeomorphology of the Jiamuhe Formation,and the favorable reservoircap assemblage was formed together with the weathering clay rock above them.Within the banded nappe,the faults intersect,the fault traps were well developed,and a northsouth hydrocarbonenriched belt was formed in the Jiamuhe Formation of Zhongguai lift,Junggar Basin.