基于小波变换的频率衰减梯度属性含气性检测

时频分析是实现地震分频解释的重要手段,提高时频分析方法的精度和分辨率至关重要。根据岩性油气藏的特点,提出了利用基于小波变换的时频分析方法进行岩性油气藏储层预测的思路,此方法克服了传统傅立叶时频转换时的时窗问题,提高了地震资料频域内的分辨能力。散射理论的研究结果表明当地层中储层含油气时,由于弹性系数、阻力系数、密度、速度发生大的变化,其固有频率显著改变,表现在频段上为低频共振能量增强,高频衰减能量变弱的现象,研究实例表明频率衰减梯度检测技术可以作为一种储层预测和油气检测的有效直接方法。

Frequency attenuation gradient attribute of hydrocarbon potential detection based on wavelet transform

Time-frequency analysis is a very important method of achieving seismic spectral decomposition interpretation,and it is essential to improve accuracy and resolution of Time-frequency analysis method.According to the characteristic of lithologic hydrocarbon reservoir,we proposed idea of using wavelet transform based Time -frequency analysis method to predict lithologic hydrocarbon reservoir.The method of Time-frequency analysis basing on wavelet transform overcome the traditional Fourier Time- frequency conversion of the time window problem,and improve resolution capability of seismic data in frequency domain,The research results of scattering theory show that when the reservoir have oil and gas,its inherent frequency change greatly for the changes of elastic modulus,resistance coefficient,density,velocity.The changes of its inherent frequency represent in that low frequency is resonance that its power is enhance.the high frequency is attenuation that its power die down.A case of study show that frequency attenuation gradient detection techniques can be used as a effective aids of reservoir prediction and hydrocarbon detection