基于波动方程预测的Radon变换多次波衰减方法

发布时间：2018-03-09 20:39

本文选题：多次波　切入点：抛物Radon变换　出处：《东北石油大学》2015年硕士论文　论文类型：学位论文

【摘要】：目前,在地震数据处理中,通常将多次波视为噪音进行衰减,常用方法有基于波动方程法和滤波法,前者基于数据驱动,无需地下介质的先验信息,可以处理复杂地下介质,但计算成本较高,且要求全波场地震数据,后者计算效率较高,但以多次波与一次波有较大时差为假设,对复杂介质的地震资料,常常无法获得理想的多次波衰减效果。本文提出结合基于波动方程的表面多次波衰减(SRME)和滤波法压制表面多次波,首先利用SRME方法预测多次波模型,并以此为参考,在抛物Radon域设计Butterworth型滤波器,有效滤出多次波,反变换后,借助于原始数据,获得最终的多次波衰减结果。在多次波预测过程中,引入了GPU并行加速计算技术,大幅度提高了计算效率。传统抛物Radon变换无法准确计算由于多点同时放炮或地下介质倾斜起伏不平造成的多炮叠加地震数据,为此引入空间频率域的顶点移动Radon变换算法,用来计算抛物线顶点在空间任意位置处的同相轴,将其能量团成像于真实的空间位置。另外,为了进一步消除Radon域的假频问题,提高成像精度,本文还提出利用时间延迟量Γ代替传统抛物Radon变换的曲率参数q,沿地震记录同相轴进行积分运算。当使用时延Radon变换时,输入数据的道数将作为重要参数直接影响Radon变换域的假频,而非传统抛物Radon变换空间方向的采样间隔。使用预条件算子通过重建间接增加输入数据的道数,进而更好的实现多次波压制。数据测试表明,文中所提出方法改善了计算精度,提高了计算效率,有效抑制了Radon域假频,充分发挥了基于波动方程预测方法和抛物Radon变换方法衰减多次波的各自优势,可以成功处理复杂介质地震资料,在海洋地震资料表面多次波衰减中有较好的应用和发展前景。
[Abstract]:At present, in seismic data processing, multiple waves are usually regarded as noise attenuation. The common methods are based on wave equation method and filtering method. The former is based on data driven and can deal with complex underground media without prior information of underground media. But the calculation cost is high, and the full wave field seismic data are required. The latter is more efficient, but the seismic data of complex medium is assumed to have large time difference between multiple wave and primary wave. In this paper, the method of surface multiple attenuation based on wave equation and filtering method are proposed to suppress the surface multiple wave. First, the SRME method is used to predict the multiple wave model, which is taken as a reference. A Butterworth filter is designed in parabolic Radon domain to filter out multiple waves effectively. After inverse transformation, the final attenuation results of multiple waves are obtained by means of original data. In the process of multiple wave prediction, GPU parallel accelerated computing technique is introduced. The traditional parabolic Radon transform can not accurately calculate the seismic data caused by the simultaneous firing of multiple points or the uneven tilt of underground media. Therefore, the algorithm of vertex moving Radon transform in spatial frequency domain is introduced. This method is used to calculate the in-phase axis of parabola vertex at any position in space, and image its energy group in real space position. In addition, in order to further eliminate the false frequency problem in Radon domain and improve the imaging accuracy, In this paper, we also propose to use the time-delay parameter 螕 instead of the curvature parameter Q of the traditional parabolic Radon transform to perform integral operations along the in-phase axis of seismic records. When the time-delay Radon transform is used, As an important parameter, the number of traces of input data will directly affect the false frequency of Radon transform domain, rather than the sampling interval in space direction of parabolic Radon transform. The preconditioned operator is used to indirectly increase the number of traces of input data through reconstruction. The test results show that the proposed method improves the accuracy and efficiency of calculation and effectively suppresses the false frequency in Radon domain. The methods of wave equation prediction and parabolic Radon transform are used to attenuate multiple waves, which can be used to deal with seismic data of complex media successfully. It has a good application and development prospect in ocean seismic data surface multiple attenuation.
【学位授予单位】：东北石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P631.4

【相似文献】