松辽盆地三肇地区宋芳屯油田扶余油层成岩作用对储层的影响  

Influence of Diagenesis on Fuyu Reservoir in the Songfangtun Oilfield in Sanzhao Area of Songliao Basin

作　　者：方庆[1] 王宝清[2] 雷友忠[1] 熊霄[1] 

机构地区：[1]中石油大庆油田有限责任公司第八采油厂,黑龙江大庆163514 [2]西安石油大学油气资源学院,陕西西安710065

出　　处：《石油天然气学报》2012年第4期41-46,165-166,共6页Journal of Oil and Gas Technology

基　　金：中国石油天然气集团公司项目(082008E)

摘　　要：用常规偏光显微镜、阴极发光显微镜、常规物性、粒度分析、压汞分析、扫描电镜、X射线衍射对宋芳屯油田扶余油层储集岩的成岩作用进行了综合研究。储集岩主要为高泥岩岩屑含量的细-极细粒长石岩屑砂岩。储集空间主要为缩小的原生粒间孔,具有低孔、低渗,变化大的排驱压力、孔喉半径和最大进汞饱和度,低的退出效率特征。对储层起破坏性的成岩作用主要有压实作用、胶结作用,起建设性的成岩作用主要是溶蚀作用。高的地温梯度、细的碎屑粒度和高的泥岩岩屑含量是压实作用下沉积物(岩)孔隙大大降低的关键因素。方解石的胶结作用是次于压实作用对储层起重要的破坏作用。长石和中基性火山岩岩屑的溶蚀对储层是重要的建设性作用。成岩作用早期的少量碳酸盐胶结物,可以抵抗压实作用;成岩作用早期沉淀的微晶石英、绿泥石包壳均有利于抵抗石英加大,两者均使得孔隙在一定程度上得以保存。Microscope,cathodoluminescence microscope,ordinary physical properties,grain size analysis,mercury injection method,scanning electron microscope and X-ray analysis were often used for comprehensively studying the diagenesis of the Fuyu Reservoir in Songfangtun Oilfield.The reservoir rocks were mainly of fine-very fine feldspathic litharenite with high content of mudstone fragments.Reservoir space was mainly of reduced original intergranular pore.The reservoir had the characteristics of low porosity and permeability,changeable displacement pressures,pore-throat radius and maximum mercury saturation,and low mercury withdrawal efficiency.Compaction and cementation induced damage to the reservoirs,while the dissolution enhanced the porosity.The high geothermal gradient,fine size of framework grains and abundant mudstone fragments were the key factors greatly reducing the porosity of sediments under the compaction.Calcite cement was the next factor for reducing the porosity.The dissolution of feldspar and intermediate basic volcanic rock fragments played an important and constructive role of reservoirs.The minor amount of carbonate cements,which is formed during early diagenesis,can resist against compaction and preserve pores.Microquartz rim,grain-rimming chlorite formed during early diagenesis can preserve the porosity through the inhibition of cementation by quartz overgrowths.

关 键 词：三肇凹陷 扶余油层 低孔渗 压实作用 胶结作用 

分 类 号：P618.13[天文地球—矿床学]