小波分析在油气田地球物理勘探中的应用

Application of Wavelet Analysis in Geophysical Exploration of Petroleum-Gas Fields

阐明了具有Ｌｉｐｓｃｈｉｔｚ指数的地震道信号奇异性的数学特征。对油气勘探区的实际人工地震资料，选取具有紧文集的二次样条函数作为小波基。然后将采样所得的数据作离散二进小波变换，采用Ｍａｌｌａｔ塔式算法对地震波信号进行分解与重构。计算出小波变换模的极大值，并与所给阈值进行比较。由该奇点所对应的时间ｔ确定其深度位置，从而对地震道资料进行高分辨率处理。采样间隔为Δｔ＝２ｍｓ，采样区间为［９００，１４００］，采样数据个数为２５１．用实际测井资料检验，彼此十分吻合。

Explains the mathematical characteristics of the singularities of signals of seismictrack with the LipschitZ index .chcicing the quadratic spline functions with compact support set as thewavelet bases for the practical artificial seismic data of the reston of petroleum-gas exploration,teking the discretized dyadic wavelet transforms for the data obtained by sampling, and applying theMallat pyramid algorithm to decomposite and reconstruct the seismic wave signal, computing themaximal moduli of the wavelet transforms,and comparing with the thresholds. From the time t correspondins to the sinsularity point one may determine the position of deep of the orebody,consequently acomplishing the hish resolution for the data of seismic track. The sample steplength is Δt=2 ms. The sample interval is [900, 1400] and the number of sample data is 251. Testing by thepractical data of the drilling wells,they agree quite well with each other.