摘要
针对储集空间多样、非均质性强的碳酸盐岩储层,由于内部孔隙结构复杂,常规的岩石物理分类方法难以准确地划分储层类别,特别是对孔喉半径呈现双峰、三峰等多峰分布的复杂多孔隙系统。本文以中东某油田M组碳酸盐岩储层为研究对象,明确了岩石内部孔隙结构决定孔喉半径分布特征,进而影响岩石的类型划分。因此从孔喉大小分布入手,考虑多峰样品中每个峰对应孔隙组分对岩石储集空间及渗流作用的贡献,以累积渗透率曲线为依据,提出了结合孔喉大小及其占比的组合孔喉半径参数(Rmax^(*))来表征岩石的孔隙结构,并对选取的114块双峰及43块三峰岩样进行分类。结合物性、压汞、薄片、测井等资料,对每类储层特征展开了深入研究。结果表明,相比于利用单一孔喉半径(Winland R35)的分类结果,Rmax^(*)可以更好地表征储层孔隙结构,提高储层的分类效果。
Since carbonate reservoirs characterized by diverse reservoir spaces and high heterogeneity exhibit intricate internal pore structures,conventional petrophysical classification methods fail to accurately classify these reservoirs,especially the reservoirs with complex porous systems whose pore throat radii manifest a multimodal(e.g.,bimodal,and trimodal)distribution.By investigating the M Formation's carbonate reservoirs in an oil field in the Middle East,this study clarified that the internal pore structures of rocks determine the pore throat radius distribution,which in turn affects the classification of rocks.Hence,starting with the pore throat size distribution,and considering the contribution of pore components corresponding to each peak in the multimodal samples to the rock reservoir space and seepage capacity,this study proposed a pore throat radius parameter Rmax^(*)combining pore throat sizes and their proportions to characterize the pore structures of rocks based on the cumulative permeability curve.Then,this study classified the selected 114 bimodal and 43 trimodal rock samples.Moreover,the characteristics of each type of reservoir were examined in depth by combining with physical properties,mercury injection data,thin-section observational data,and logs.The results of this study show that Rmax^(*)can better charac-terize the pore structures of reservoirs and improve the reservoir classification effectiveness compared with the classification based on a single pore throat radius(R35,corresponding to mercury saturation of 35%).
作者
赵冰
ZHAO Bing(Exploration and Development Research Institute,Sinopec Jianghan Oilfield Company,Wuhan430074,China)
出处
《物探与化探》
CAS
2024年第1期134-141,共8页
Geophysical and Geochemical Exploration
基金
中国石油化工股份有限公司科技攻关项目“江汉油田低渗致密油藏有效动用关键技术研究”(P20069-5)。
