吉林红岗北地区泉头组岩性油藏储层特征

Reservoir characteristics of lithologic pool in Quantou Formarion,the north of Honggang area.Jilin province

通过岩心观察、薄片鉴定、物性分析和扫描电镜观察等技术手段,研究了红岗北地区泉头组岩性油藏储层的岩石学特征、成岩作用、孔隙结构、储层物性及影响因素。研究结果表明,红岗北地区泉头组岩性油藏储层的岩性主要以长石岩屑砂岩为主,成分成熟度和结构成熟度较低。目的层段成岩作用强烈,先后经历了压实作用、胶结作用和溶解作用,属于成岩作用晚成岩B段。储集空间类型以粒间孔和次生溶孔最为发育,储层的物性主要受成岩作用和沉积微相双重因素控制,孔隙度和渗透率较低。储层在垂向上压实和胶结作用使储层物性明显变差,而溶蚀作用产生次生孔隙使储层物性得到改善,平面上储层物性受沉积相带控制。综合分析认为沉积作用控制储层的平面分布,分流河道微相和废弃河道微相是油气聚集的有利相带,是开发的主要区带。

Through core observation and by virtue of technical methods such as slice appraisal,physical property analysis and scanning electron microscope observation,the lithology characteristics,the diagenesis,the pore structure,the phys- ical properties and influential factors of Quantou Formation in the north of Honggang area,Jilin province,are studied. Results indicate that the reservoir lithology of lithologic pool in Quantou Formation is mainly feldspar lithic sandstone in the north of Honggang area,with components and structure of low maturity.Due to strong diagenesis,the sandstones in the reservoir have undergone compaction,cementation and dissolution,which is the stage-B of late diagenesis.Reser- voir spaces are mainly the intergranular pores and the sec- ondary solution pores.The physical properties were doubly affected by diagenesis and sedimentary microfacies,so the porosity and the permeability are low.The vertical compac- tion and cementation made these physical properties obvious- ly low,but the dissolution generated secondary pores that improve the physical properties.And the lateralphysical properties of reservoir are subject to the sedimentary facies. Integrative analysis shows that the subaqueous distributary channel and the abandoned channel micro-facies were favor- able facies belt for hydrocarbon accumulation,hence the tar- gets of exploration.