摘要
针对涠洲油田不同气油比油层具有相近中子挖掘效应特征,造成高气油比油层识别困难的问题。利用测井解释、油层测试分析、岩电实验和数值模拟等方法,对不同气油比油层测井响应特征、形成机理和侵入带电阻率影响因素等方面进行综合研究表明:①中高气油比油层具有近乎接近的中子挖掘测井响应特征。只有在低气油比及相近地层压力情况下,中子挖掘效应法才能有效区分气油比高低,它是一种“窄谱”识别方法。②油气流体压缩系数对气油比变化很敏感,气油比越高,油气流体压缩系数越大,二者呈近似线性关系。利用油气流体压缩系数识别油层气油比方法,是一种“广谱”识别新方法。③通过求取重构后阵列感应电阻率测井曲线间互信息矩阵,可使隐含在阵列感应电阻率测井资料中气油比高低信息得到放大,互信息矩阵中互信息值的大小近似反映气油比高低信息。基于互信息矩阵的气油比识别方法,克服了中子挖掘效应法的适用限制条件,实现利用油气流体压缩系数对不同气油比油层的“广谱”识别。
Identifying oil layers with high gas-oil ratios in the Weizhou Oilfield is difficult because of the similar neutron excavation effect characteristics in oil layers with different gas-oil ratios.To address this problem,the logging response characteristics,formation mechanism,and influencing factors of the resistivity response in the invasion zone of oil layers with different gas-oil ratios were studied by synthetically using log interpretation,oil layer test analysis,rock electricity experiments,and numerical simulations.The results indicate the following:①high gas-oil ratio oil layers have neutron excavation logging response characteristics that are close to those of medium gas-oil ratio layers.The neutron excavation effect method,which is a“narrow-spectrum”identification method,can only effectively distinguish gas-oil ratios when they are low and have close formation pressure.②The oil-gas fluid compressibility is sensitive to the change in the gas-oil ratio;the higher the gas-oil ratio,the greater is the oil-gas fluid compressibility.A nearly linear relationship exists between the gas-oil ratio and the oil-gas fluid compressibility,which could serve as a new“broad-spectrum”identification method to identify the gas-oil ratio by compressibility of the oil-gas fluid.③By calculating the mutual information matrix between the reconstructed array induction resistivity logging curves,information about the gas-oil ratio implicitly contained in the logging data of array induction resistivity can be highlighted.The value of mutual information in the matrix approximately reflects the information regarding the gas-oil ratio.The gas-oil ratio identification method based on a mutual information matrix can overcome the limitations of the neutron excavation effect method,and the“broad-spectrum”identification of different oil-gas ratios of the oil layer can be realized by using oil-gas fluid compressibility.This method has achieved good results in the application in the Weizhou Oilfield in the Beibu Gulf Basin of the South China Sea and provides a new idea for the quantitative identification of the gas-oil ratio of oil reservoirs in similar oilfields.
作者
王任一
张登辉
郭书生
黄导武
许彪
WANG Renyi;ZHANG Denghui;GUO Shusheng;HUANG Daowu;XU Biao(School of Petrochemical Engineering and Environment,Zhejiang Ocean University,Zhoushan Zhejiang 316022,China;Zhanjiang Branch of CNOOC Ltd.,Zhanjiang Zhejiang 524057,China;Shanghai Branch of CNOOC Ltd.,Shanghai 200030,China)
出处
《地球科学进展》
CAS
CSCD
北大核心
2022年第8期851-862,共12页
Advances in Earth Science
基金
浙江省自然科学基金项目“基准面旋回沉积响应机理定量研究”(编号:LY20D020002)
国家科技重大专项项目“基于边界层理论的非线性渗流模型研究”(编号:2017ZX05072005)资助
关键词
高气油比油层
中子挖掘效应
流体压缩系数
侵入带电阻率响应
互信息矩阵
High gas-oil ratio oil layer
Neutron excavation effect
Fluid compressibility
Resistivity response of invaded zone
Mutual information matrix
作者简介
First author:王任一(1968-),男,甘肃天水人,副教授,主要从事海洋油气资源开发教学与研究工作.E-mail:wangry0123@163.com
