地层元素测井在致密砂岩储层中的应用分析

地层元素测井技术以各种已知元素的特征能谱为基础,通过谱剥离处理及氧化物闭合模型得到了地层中元素百分含量,在此基础上进行成岩矿物含量计算、划分地层岩性、确定岩石骨架参数。结合鄂尔多斯盆地陇东地区长7段储层常规测井资料,利用骨架密度和Lambda渗透率模型计算长7段致密砂岩储层孔隙度和渗透率,提高储层参数计算精度。基于地层元素百分含量建立烃源岩总有机碳含量TOC计算模型,计算结果与岩石物理实验分析结果基本一致。地层元素测井技术在致密砂岩储层中适用,为致密砂岩储层测井识别及评价提供有效手段。

Analysis of Application Effect for Formation Element and Mineralogy Logging in Tight Sandstone Reservoir

The Formation Element and Mineralogy(FEM)logging technology is based on the spectral characteristic of various known elements.Through spectral stripping and oxide closure model,the element content in the formation can be obtained.Furthermore,the caculation of diagenetic mineral content,the classification of formation lithology and the determination of rock skeleton parameters can be conducted.Combined with conventional logging data of Chang7 member reservoir in Longdong area of Ordos basin,the veracity of the calculated reservoir parameters,such as porosity and permeability of tight sandstone reservoir in Chang7 formation,is highly improved by using skeleton density and Lambda permeability model.The TOC calculation model of source rocks is established based on the element contents of formations.The calculation results are basically consistent with the petrophysical experimental analysis results.FEM logging technology is applicable to tight sandstone reservoirs and provides an effective method for identification and evaluation of tight sandstone reservoir.