改进的U-Net网络小断层识别技术在玛湖凹陷玛中地区三叠系白碱滩组的应用  

Application of improved U-Net network small faults identification technology to Triassic Baijiantan Formation in Mazhong area,Mahu Sag

作　　者：宋志华 李垒 雷德文[1] 张鑫[1] 凌勋[1] SONG Zhihua;LI Lei;LEI Dewen;ZHANG Xin;LING Xun(Exploration Division,PertoChina Xinjiang Oilfield Company,Karamay 834000,Xinjiang,China;College of Geophysics,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]中国石油新疆油田公司勘探事业部,新疆克拉玛依834000 [2]成都理工大学地球物理学院,成都610059

出　　处：《岩性油气藏》2024年第3期40-49,共10页Lithologic Reservoirs

基　　金：国家自然科学基金“基于频变信息的流体识别及流体可动性预测”(编号:41774142)资助。

摘　　要：利用改进的U-Net网络小断层识别技术,对准噶尔盆地玛湖凹陷玛中地区三叠系白碱滩组的小断层进行了识别。研究结果表明:(1)构造导向滤波预处理能有效改善地震资料的品质,提高断层识别的准确率。加入了跳跃连接和中继监督、正态标准化和聚焦均方损失函数的U-Net网络方法,对小断层的精细识别能力有所提升。(2)使用200组训练样本集和20组验证样本集,模型地震数据由反射系数与雷克子波褶积生成,断层由人工标注而成。选取最优的网络模型参数,并在合成的含噪地震数据上分别利用相干属性、常规U-Net网络方法及改进的U-Net网络方法进行测试,构造导向滤波有效突出了断层的边界,且增强了同相轴的横向连续性,改进后的U-Net网络方法对于7 m以上断距的断层可进行有效识别。(3)对于玛湖凹陷玛中地区三叠系白碱滩组高角度走滑断裂和伴生小断距次级断裂的识别,改进后的U-Net网络方法的识别精度明显高于相干属性和常规U-Net网络方法,研究区大侏罗沟断裂北翼的(3)号与(4)号砂体,是拓展MZ4井区三叠系白碱滩组高效勘探的有利区。The small faults of Triassic Baijiantan Formation in Mazhong area of Mahu Sag in Junggar Basin were identified by using the improved U-Net network small fault identification technology.The results show that:(1)Construct-guided filtering preprocessing can effectively improve the quality of seismic data and increase the accuracy of fault identification.The U-Net network,which incorporatesskip connections,relay supervision,normal standardization,and focused mean square loss function,has improved its fine identification ability of small faults.(2)Using 200 training sample sets and 20 validation sample sets,the seismic data of the model were generated by convolution of reflection coefficients and Ricker wavelet,and faults were manually labeled.Optimal network model parameters were selected to test on the synthesized noisy seismic data by using coherent attributes,conventional U-Net network methods,and the improved U-Net network method.Construct-guided filtering effectively highlighted the boundaries of faults and enhanced the lateral continuity of the same phase axis.The improved U-Net network method can effectively identify faults with a fault distance of more than 7 meters.(3)The improved U-Net network method has significantly higher accuracy than coherent attributes and conventional UNet network methods in identifying high-angle strike-slip faults and associated secondary faults with small fault throw of Triassic Baijiantan Formation in Mazhong area of Mahu Sag.The No.3 and No.4 sand bodies in the northern Dazhuluogou fault in the study area are favorable areas for efficient exploration of Triassic Baijiantan Formation in MZ4 well area.

关 键 词：U-Net网络 断层识别 高角度走滑断裂 伴生小断距次级断裂 正态标准化 聚焦均方损失函数 白碱滩组 三叠系 玛湖凹陷 

分 类 号：TE319[石油与天然气工程—油气田开发工程] P631.4[天文地球—地质矿产勘探]