The effect of inhomogeneous water on seismic imaging in deepwater areas of the South China Sea  

作　　者：JI LiLi LIN Mian HAO TianYao 

机构地区：[1]Institute of Geology and Geophysics, Chinese Academy of Sciences [2]Institute of Mechanics, Chinese Academy of Sciences

出　　处：《Chinese Science Bulletin》2013年第35期4443-4449,共7页

基　　金：supported by the National Natural Science Foundation of China(41074058,41074097 and 41210005);the National Basic Research Program of China(2009CB219405-1)

摘　　要：This paper examines the effect of inhomogeneous water on seismic imaging in deep water areas.An appropriate partial differential equation is derived for the acoustic pressure field in inhomogeneous water,including current effects.Seismic wavefields are simulated and the results show that the traveltime of seismic waves can be affected.The maximum traveltime perturbation at zero offset is 20 ms.In particular,the structure of horizontal reflectors below the water is distorted by mesoscale eddies.Variations of water temperature are the fundamental cause of the distortion.Finally,a calibration method for the distortion of seismic imaging caused by inhomogeneous water is presented.This paper examines the effect of inhomogeneous water on seismic imaging in deep water areas. An appropriate partial differen- tial equation is derived for the acoustic pressure field in inhomogeneous water, including current effects. Seismic wavefields are simulated and the results show that the traveltime of seismic waves can be affected. The maximum traveltime perturbation at zero offset is 20 ms. In particular, the structure of horizontal reflectors below the water is distorted by mesoscale eddies. Variations of water temperature are the fundamental cause of the distortion. Finally, a calibration method for the distortion of seismic imaging caused by inhomogeneous water is presented.

关 键 词：地震成像 深水区 中国南海 非均匀 地震波场 微分方程式 传播时间 校正方法 

分 类 号：P631.46[天文地球—地质矿产勘探]