基于小波变换提取吸收系数方法及应用

Extraction method of absorption coefficient based on wavelet transform and its application

周喆 桂志先 王宁

长江大学地球科学学院，湖北 荆州 434023 油气资源与勘探技术教育部重点实验室（长江大学），湖北 荆州 434023 长江大学学校办公室，湖北 荆州 434023

地震信号的衰减吸收与岩石岩性、地层含油气情况密切相关，地震信号的频率信息能较敏感地反映地层吸收系数的影响。地震信号具有持续时间短、突变快等特点，属于典型的非平稳随机信号。小波变换能够对信号进行精确的时频分析，同时小波函数的多样性使小波变换具有很强的灵活性和适应性。在实际勘探区域的数据中，利用小波变换进行时频分析，并利用频谱比法对小波变换的振幅谱提取吸收系数。应用结果表明，该方法对含气储层的识别效果较好，对后期开发工作有较好借鉴意义。

Attenuation and absorption of seismic data are closely related to rock lithology and hydrocarbon situation in reservoir. The frequency information of seismic signal can reflect the effect of stratigraphic absorption coefficient sensitively. The seismic signals belong to typical non-stationary random signals which are usually shorter in duration and faster in acquiring mutation. Wavelet transform can make a precise time-frequency analysis for the signals, and at the same time, the diversity of wavelet function make the wavelet transform show the great flexibility and compatibility. Through the time-frequency analysis with wavelet transform and through the extraction of absorption coefficient of wavelet transform amplitude spectrum with spectral ratio, actual application results show that the method presents a good effect in identifying gas-bearing reservoir and has a reference for late exploitation.

10.6056/dkyqt201303005