含噪地震剖面中反射信号的增强

ENHANCEMENT OF REFLECTION SIGNAL IN NOISY SEISMIC SECTIONS

清华大学自动化系

叠后地震剖面中,反射信号在空间上具有相干的特性.利用这一特性,本文提出了一种信号增强的方法,即沿反射信号相干方向用最小平方误差准则对信号作线性估计.为了正确确定含噪地震剖面的相干方向,文章首先确定使相似度量为最大的方向,然后再用中值滤波平滑这些方向,所得的结果基本上可以表示反射信号相干方向.为了保证断点不被模糊和横向分辨率不降低,文中定义了右相似度和左相似度,从而使我们可以向左或向右做信号估计.实际资料方面的例子表明,本文提出的方法对含噪声剖面具有很好的增强信号的能力.

Reflection signal is spatial coherent in a stacked seismic section, with this property, we have devoloped a method of signal enhancement which makes the linear estimation of signal along the coherence direction of reflection signal based on the least square error criterion. In order to determine the coherence directions correctly in noisy seismic sections, first, we determine the directions which make a similarity measure maximum, and then smooth the directions with a median filter. So, the results can indicate the coherence directions. In order to make faults not blurred and lateral resolution not reduced, we define the left and right similarity measures, so we can estimate signal towards the left or right. Examples on the real datas show the good ability of the method to enhance signal in noisy seismic sections.