SN地区辉绿岩下弱信号宽方位采集与成像  

Wide azimuth acquisition and imaging of weak signals under igneous rocks in SN area

作　　者：陈习峰[1] 薛永安[1] 庞全康[1] 朱峰[2] 石一青[2] CHEN Xifeng;XUE Yong'an;PANG Quankang;ZHU Feng;SHI Yiqing(Geophysical Research Institute of Jiangsu Oilfield Company,SINOPEC,Nanjing 210046,China;East China Branch of Sinopec Geophysics Co.,Ltd.,Yangzhou 225007,China)

机构地区：[1]中国石化江苏油田分公司物探研究院,江苏南京210046 [2]中国石化地球物理华东分公司,江苏扬州225007

出　　处：《复杂油气藏》2021年第4期47-53,共7页Complex Hydrocarbon Reservoirs

基　　金：中国石化江苏油田分公司科技项目“永安高密度三维精确成像关键处理技术研究及应用”(JS19007)。

摘　　要：高邮凹陷古近系辉绿岩广泛发育,SN地区最为典型。辉绿岩强反射是该区地震资料信噪比较低的主要原因之一。为了提高辉绿岩下成像质量,不仅需要精准压制多次波等强干扰,还需要加强辉绿岩强能量屏蔽机理分析,进而找到增强岩下弱信号的措施。通过从纵向和横向两个维度分析辉绿岩对岩下地层的地震反射能量影响,充分利用辉绿岩空间分布的局限性和差异性等特性,提出以宽方位为核心的地震资料采集处理一体化解决方案。SN地区宽方位一体化成像攻关及观测系统退化分析证实:覆盖次数有一定保证时,观测方位的进一步增加更为重要。在此基础上做好分频能量补偿和优势方位成像,能够在最大程度上克服辉绿岩对下伏地层的屏蔽作用,实现辉绿岩下弱反射信号较好质量的成像。The tertiary igneous rocks are widely developed in Gaoyou Sag,and the SN area is the most typical.The strong reflection of igneous rocks is one of the main reasons for the low signal-to-noise ratio of seismic data in this area.In order to improve the imaging quality under igneous rocks,it is not only necessary to accurately suppress strong interference such as multiple waves,but also to strengthen the analysis of the strong energy shielding mechanism of igneous rock,and then find measures to enhance weak signals under the rocks.By analyzing the influence of igneous rocks on the seismic reflection energy of the substrata from the vertical and horizontal dimensions,and making full use of the limitations and differences of the spatial distribution of igneous rocks,it was proposed an integrated solution of seismic data acquisition and processing with wide-azimuth as the core.The wide-azimuth integrated imaging research and the degradation analysis of the observation system in the SN area confirmed that the further increase of observation azimuth is more important when the coverage times are guaranteed to a certain extent.On this basis,frequency division energy compensation and dominant azimuth imaging can overcome the shielding effect of igneous rocks on underlying strata to the greatest extent,and achieve better quality imaging of weak reflection signals under igneous rocks.

关 键 词：高密度 宽方位 能量补偿 分方位速度分析 井约束建模 辉绿岩 阜宁组 高邮凹陷 

分 类 号：P631[天文地球—地质矿产勘探]