三参数小波分频处理在走滑断层识别中的应用

Application of three parameter wavelet frequency processing to the recognition of strike-slip fault

压扭应力场环境下形成的走滑断层一般具有断面陡立,在剖面上呈花状等特点,其构造特征复杂,剖面解释和空间组合难度较大。同一地震剖面的浅、中、深层的资料品质有差异,断点、断面的清晰度也不同。以地质背景为基础,针对不同层段采用不同主频的地震资料进行断层解释,能够增强其可靠性。三参数小波变换具有比傅里叶变换、Morlet小波变换更好的时频聚焦性,可以使断层在不同主频的地震剖面上取得最佳的成像效果,有利于人工解释并提高其可信度。南堡凹陷走滑断层发育,这里采用三参数小波分频处理技术,针对该区块的地震资料进行处理并用于断层解释,取得了较好的效果。

Generally,strike-slip fault formed under pressure torsion stress field has the characteristics of steep section,flower structure,etc.Its structural feature is complex,and it is difficult to accomplish fault interpretation.The data quality of the same seismic profile at shallow,middle and deep segment has great difference.Therefore,the definition of breakpoints and fault section is also different.Based on the geological background,the Reliability of fault interpretation can be improved by u-sing seismic data with different dominant frequency at different interval.Three parameter wavelet transform is much better than Fourier transform and Morlet wavelet transform in time-frequency focusing.The best effect of fault imaging can be obtained by this method in different dominant frequency of seismic profiles,and it is also convenient for manual interpretation and credibility enhancement.There are large amount of strike-slip faults in Nanpu Sag.Three parameter wavelet frequency processing tech-nique has been applied to seismic data processing and fault interpretation and better effect has been achieved.