摘要
下扬子南部属于低信噪比地区,受近地表激发介质影响,地震采集资料品质较差,激发介质的选择是该区地震采集工作面临的主要难题。综合多种方法建立地质模型,根据不同位置的野外取心结果、将岩性特征划分为四类黏土样品,并测试其岩石物理参数;基于最大弹性势能准则,建立物性参数与弹性势能之间的关系。研究认为,Ⅱ类样品的弹性势能与周围介质阻抗匹配均较好,计算不同样品类型的子波特征参数,Ⅱ类介质的主频、频带宽度和振幅能量综合指标最好;对不同类型样品进行正演模拟,Ⅱ类样品模拟的单炮在中-远排列深层4 s有反射波组存在。对比同一构造相邻位置优选激发岩性前后的单炮,优选激发介质后的单炮资料在信噪比和目的层波组连续性上均优于优选激发介质前的地震资料。综合分析认为Ⅱ类样品是最适合该区的激发介质。
The south of lower Yangtze is a low signal-to-noise ratio area.Affected by the near surface excitation medium,the quality of seismic acquisition data is poor.The selection of excitation medium is the main problem of seismic acquisition in this area.A geological model was established by integrating multiple methods,field coring was carried out in different locations,and four types of clay samples were divided according to the lithologic characteristics,and their rock physical parameters were tested.Based on the maximum elastic potential energy criterion,the relationship between physical parameters and elastic potential energy is established.The results show that the elastic potential energy of type II sample matches well with the impedance of surrounding medium.The comprehensive index of main frequency,frequency band width and amplitude energy of type II medium is the best when calculating the wavelet characteristic parameters of different sample types.The forward modeling of different types of samples shows that the reflection wave group exists in the 4 s deep layer of the middle-further permutation of the single shot simulated by the type II sample.Compared with the single shot before and after the optimized shooting lithology in the adjacent position of the same structure,the signal-to-noise ratio and wave group continuity of the target layer are better than those of the seismic data before and after optimizing the excitation medium.Comprehensive analysis shows that the type II sample is the most suitable excitation medium for this area.
作者
彭仁艳
刘文峰
王军锋
郝晓敏
黄伟
PENG Renyan;LIU Wenfeng;WANG Junfeng;HAO Xiaomin;HUANG Wei(Research&Development Center,Petroleum Engineering Geophysics Co.,Ltd.,SINOPEC,Nanjing,Jiangsu 211100,China;Huadong Company,Petroleum Engineering Geophysics Co.,Ltd.,SINOPEC,Nanjing,Jiangsu 211100,China)
出处
《石油地质与工程》
CAS
2020年第6期13-19,共7页
Petroleum Geology and Engineering
基金
中国石化石油工程技术服务有限公司先导试验项目(SG16-51K)。
关键词
下扬子南部
激发介质优选
弹性应变能
子波特征
south area of lower Yangtze
medium optimization
elastic strain energy
wavelet characteristics
