摘要
根据铸体薄片、扫描电镜、X-衍射、镜质体反射率(Ro)及包裹体等资料分析,对陇东地区长9油层组储集岩类型及其成岩作用特征进行了系统研究。研究区长9油层组储集砂岩目前主要处于中成岩阶段B期,部分已进入晚成岩阶段。该区储集体砂岩主要为岩屑长石砂岩及长石砂岩,少量为岩屑砂岩,成分成熟度较低。成岩作用类型丰富,主要有压实作用、压溶作用、胶结作用、交代作用、溶蚀作用、破裂作用及自生矿物充填作用等。不同成岩作用对储层造成的影响不同,其中压实作用导致原生粒间孔隙急剧减少,早期绿泥石环边胶结作用促使原生粒间孔隙得以保存,溶蚀作用能够产生新的储集空间,破裂作用提高了储层渗透性并能促进溶蚀作用的进行,而碳酸盐胶结作用导致储层非均质性增强。
Based on the analysis results of casting thin sections,scanning electron microscopy(SEM),X-ray diffraction, vitrinite reflectance(Ro),and inclusion data,the reservoir rock types and their diageneses of Chang 9reservoir in Longdong Area were comprehensively researched,it was indicated that sandstones in the Chang 9reservoir of Longdong Area were mainly at the middle diagenetic stage B,and some of them were at the late diagenetic stage.The reservoir sandstones were mainly composed of debris feldspar sandstone and feldspar sandstone with a small amount of lithic sandstone,low compositional maturity and rich diagenesis.The diagenesis types include compaction,pressure solution, cementation,metasomasis,dissolution,fracture diagenesis and cavity filling of authigenic mineral.Different diageneses cause different effects on the reservoirs.Among them,compaction would induce the decrease of primary intergranular porosity drastically;chlorite rim cementation of early period has an extremely important effect on preserving primary intergranular porosity;dissolution can generate new reservoir space;cracking would improve both reservoir permeability and dissolution;carbonate cementation would promote the enhancement of reservoir heterogeneity.
出处
《石油天然气学报》
CAS
CSCD
2013年第10期27-31,5,共5页
Journal of Oil and Gas Technology
