相对保幅的抛物线Radon变换法地震道重建

实际地震资料中常见地震道缺失或空间采样不足的问题,这不仅会导致有效信息丢失,还有可能在后续的处理中产生不利影响。为此，基于抛物线Radon变换进行缺失地震道重建的基本原理,综合考虑AVO响应特征及傅里叶变换基本性质,提出了相对保幅的抛物线Radon变换地震道重建方法。该方法是对前人提出的道均衡抛物线Radon变换地震道重建方法的一种改进，即在道均衡过程中考虑了反射振幅随偏移距的变化，根据AVO特征对不同偏移距的重建地震道采用不同的均衡系数，而不是采用固定的道均衡系数对道与道之间简单地均衡，所以可以加快重建数据向实际数据逼近的速度并提高数据重建的精度。模型数据和实际地震资料的试算结果表明,相对保幅的抛物线Radon变换地震道重建方法对于叠前地震数据的重采样及不同偏移距地震道的重建是有效可行的,不仅能够实现缺失地震道的相对保幅重建,而且可以大大提高重建效率。

 For in-situ seismic data,seismic trace missing and insufficient spatial sampling is common phenomena,which may result in not only useful information missing,but also adverse effects on data processing.For these reasons,based on the parabolic Radon transform,with the consideration of AVO response characteristics and principle properties of Fourier Transform,a relative amplitude-preserved seismic trace reconstruction method is proposed,which is a kind of improvement for the seismic trace reconstruction method by the trace equalization parabolic Radon transform.In the improved method,the trace equalization taking AVO characteristics into consideration is applied when the forward parabolic Radon transform and inverse least-square Radon transform are carried out.Because relation between seismic reflection amplitude and offset is considered in the application of trace equalization and different trace equalization coefficients will be adopted for missing traces of different offsets,not only iterations can be reduced but precision of reconstruction can be improved.Via numerical experiments of forward modeling data and real seismic data,it is proved that the improved reconstruction method proposed has high accuracy and efficiency and it is effective and feasible to apply this method to resample pre-stack seismic data and reconstruct missing seismic data of different offsets.