【摘要】 在处理表层多次波比较发育的地震数据资料时,和常规将多次波作为噪音进行压制和去除的思路不同,本文提出利用表层多次波来进行地震构造成像的方法技术流程.首先基于互相关技术将表层多次波转化为准一次波,在利用准一次波进行偏移成像之前,提出应用局部倾斜叠加变换的方法,压制由于其特殊的构建过程而常常伴随准一次波的背景干涉噪音,提高准一次波数据的信噪比;然后应用扩展的分步傅里叶偏移方法对去噪后的准一次波数据进行成像,此偏移成像方法在实现分步傅里叶方法时选取多个背景参考速度,不仅继承常规分步傅里叶偏移方法稳定高效,没有有限差分计算存在的频散影响的特点,而且可以增强常规分步傅里叶偏移方法处理复杂陡倾构造的能力.通过数值模拟数据测试,说明本文提出的这一套利用表层多次波进行复杂地下构造成像的方法技术的可行性和有效性.更多还原

【Abstract】 his paper proposes the method and technique for imaging of surface-related multiples,when processing seismic data with surface-related multiples.Firstly,we use cross-correlation technique to make pseudo-primary from surface-related multiples,the pseudo-primary is often blurred by the interference noise because of unpaired primary and multiple events.So next,we employ a linear transform of local slant stack to suppress the interference noise and improve its signal to noise ratio;Last but not least,we propose using extended split-step Fourier migration method to realize imaging of pseudo-primaries.Compared with conventional split-step Fourier method,the migration method use multi reference velocities when doing migration,so it is more suitable for migrating seismic data from areas complicated velocity structures.A test on Sigsbee2b dataset shows that the method is effective for improving the signal-to-noise ratio of imaging of pseudo-primary and imaging complicated velocity structures.更多还原