摘要
采用P型核磁在黔北地区AX页岩气工区开展了两种模式二维核磁共振测井,根据横向弛豫谱峰(T_(2))分布特征和天然气信号特征进行了测量模式优选。对比了研究区与邻区储层地质特征,参考邻区核磁共振测井实验数据,结合实测谱峰特征,合理选取T_(2)截止值进行核磁数据处理,开展了龙马溪组一段富有机质页岩储层孔隙度参数计算、孔隙结构分析,流体组分识别等工作,其中龙一1^(1)-龙一1^(2)底部层段核磁有效孔隙度平均4.8%,储层大孔径主要分布在在32~256 ms之间,T_(2)-T_(1)交会可动气区域信号最强,评为Ⅰ类储层。结合常规测井分析结果,证实了(T_(2)-T_(1))二维核磁共振测井技术在低孔隙度页岩气储层测井评价中的准确性和适用性。结合元素测井计算的黄铁矿含量,简要分析了黄铁矿对核磁共振测井信号可能的影响作用,研究成果对类似地质条件下的页岩储层二维核磁共振测井评价提供了一定的参考作用。
Two modes of 2D nuclear magnetic resonance logging were conducted using P-type nuclear magnetic resonance in the AX shale gas work area in northern Guizhou.The measurement mode was optimized based on the distribution characteristics of transverse relaxation spectrum peaks and natural gas signal features.By comparing the geological characteristics of the reservoir in the study area with those in the neighboring area,referring to the experimental data of nuclear magnetic resonance logging in the neighboring area,and combining with the measured spectral peak characteristics,the T_(2) cut-off value was reasonably selected for nuclear magnetic data processing.The porosity parameters calculation,pore structure analysis,and fluid component identification of the organic rich shale reservoir in the first member of Longmaxi Formation were carried out.The average nuclear magnetic effective porosity was 4.8%of the layer S_(1) l^(1) and bottom of S_(1) l_(2),and the large pore size of the reservoir was mainly distributed between 32~256 ms.The signal in the T_(2)-T_(1) intersection movable gas area was the strongest,and it was rated as a class I reservoir.Combined with conventional logging analysis results,the accuracy and applicability of the(T_(2)-T_(1))2D nuclear magnetic resonance logging technology in the logging evaluation of low porosity shale gas reservoirs have been confirmed.Based on the calculation of pyrite content using elemental logging,a brief analysis was conducted on the possible impact of pyrite on nuclear magnetic resonance logging signals.The research results provide a certain reference for the 2D nuclear magnetic resonance logging evaluation of shale reservoirs under similar geological conditions.
作者
吴晓光
李德才
樊靖宇
吴春燕
康建云
吴家安
Wu Xiaoguang;Li Decai;Fan Jingyu;Wu Chunyan;Kang Jianyun;Wu Jia’an(Xinan MWD/LWD Logging Corporation,Sinopec Matrix Coporation,Chengdu Sichuan 610100,China)
出处
《工程地球物理学报》
2025年第6期664-674,共11页
Chinese Journal of Engineering Geophysics
基金
中石化石油工程公司项目(编号:SG23-54K)。
