摘要
阐明微相控制下的储层展布及其微观特征,对揭示油气差异富集规律,实现有利储层的评价具有重要意义。为阐明曲流河相储层特征及主控因素,以鄂尔多斯盆地胡尖山油田延9储层为例,以岩心观察描述及取样分析为基础,综合运用粒度分析、铸体薄片、扫描电子显微镜、压汞法、黏土矿物X射线衍射和常规物性分析,并结合测井资料宏观印证。结果表明:胡尖山油田延9发育曲流河相,主要包括河道(河床滞留沉积)、边滩、天然堤及河漫滩微相。储层岩性主要为长石岩屑砂岩及岩屑长石砂岩,储集空间主要为残余粒间孔和长石溶孔构成的溶孔-粒间孔组合。可识别中细喉道、细喉道及微细喉道三种主要喉道类型。孔隙度主要集中在11.51%~18.87%之间,渗透率主要为(2.08~79.86)×10^(-3)μm^(2),属于中低孔-中低渗特低渗-中大孔细喉型储层。黏土矿物、硅质及钙质的胶结作用和机械压实作用是储层致密的主因,长石颗粒及部分胶结物的溶蚀作用以及绿泥石膜对压实及胶结作用的抑制,利于原生孔隙的保存,但当绿泥石含量超过0.3%时,物性变化趋势不明显。
It is important to elucidate the reservoir occurrence and its microscopic characteristics under microfacies control,which is of great significance to evaluate the oil enrichment differences.To clarify the characteristics and constraints meandering river reservoirs,Yan 9 reservoir(Hujianshan oilfield)in the Ordos Basin is taken as an example.Based on core logging and sampling,grain size analysis,thin section observation,scanning electron microscopy,mercury injection method,clay mineral X-ray diffraction and conventional physical property analysis,and logging data verification,our work shows that meandering river facies are developed in Yan 9,and include mainly channel(river bed retention sediment),point bar,natural levee,and floodplain microfacies.The reservoir lithology comprises mainly feldspathic litharenite and lithic arkose sandstone,whilst the reservoir open-space is mainly composed of residual intergranular pores and feldspar solution pores.Three major types of throats were identified,i.e.,medium-fine throat,fine throat and micro-throat.The porosity is mainly concentrated in 11.51%-18.87%,and the permeability is mainly in(2.08-79.86)×10^(-3)μm^(2).It can be classified as medium-low porosity,medium-low permeability,extra low permeability,medium large porosity and fine throat reservoir.Cementation and mechanical compaction of clay minerals,siliceous and calcareous materials are the main cause for forming the tight reservoir.Dissolution of feldspar particles and some cement,and the inhibition of chlorite film on compaction and cementation are conducive to the primary pore preservation.Nonetheless,when the chlorite content exceeds 0.3%,the physical property change is unobvious.
作者
孙遥
郭峰
彭晓霞
向佳
张磊
杨旭东
SUN Yao;GUO Feng;PENG Xiaoxia;XIANG Jia;ZHANG Lei;YANG Xudong(Shaanxi Key Lab of Petroleum Accumulation Geology/School of Earth Sciences and Engineering,Xi’an Shiyou University,Xi’an,Shaanxi 710069,China;Shaanxi Geological Environment Monitoring Station,Xi’an,Shaanxi 710068,China;Department of Geology/State Key Laboratory of Continental Dynamics,Northwest University,Xi’an,Shaanxi 710069,China)
出处
《现代地质》
CAS
CSCD
北大核心
2022年第5期1403-1413,共11页
Geoscience
基金
国家科技重大专项“鄂尔多斯盆地大型低渗透岩性地层油气藏开发示范工程”(2016ZX05050006)。
关键词
曲流河
储层物性
控制因素
延9
胡尖山油田
meandering river
reservoir characteristic
controlling factor
Yan 9
Hujianshan oilfield
