摘要
由于地层含气,地层对高频成分吸收增强、对低频成分吸收减弱,从而在油气储集层下方形成强能量瞬时低频率区域,为利用时频分析方法直接预测含气储层提供了一定的理论依据。时频连续小波变换是对连续小波变换的改进,变换的结果是时频域,避免了尺度-频率转换过程中能量交叠的情况,因此该方法有更好的时频聚焦性。首先介绍了时频连续小波变换的基本原理,进而论述了该方法计算的关键步骤,最后理论信号试算结果与苏里格气田应用实例都证实了利用该方法检测含气厚砂岩具有一定的可行性。
Because gas was contained in strata,when seismic waves were propagated through gas-bearing strata,the high frequency attenuated strongly while the low frequency attenuation was much weaker.Then,low-frequency shadow occurred below the oil and gas reservoirs.It provided a theoretical basis for detecting the gas in reservoirs by directly using time-frequency analysis method.Time-frequency continuous wavelet transform was a new time-frequency analysis method for the improvement of continuous wavelet transform.Its result is time-frequency domain,which could avoid energy overlap in the process of scale-frequency conversion,thus it was the method for a better time-frequency concentration.The basic principles of time-frequency continuous wavelet transform are first briefly introduced and then the key steps of the method were discussed.Eventually it is proved by theoretical calculation and its application in Sulige Gas-field that the method is feasible for the detection of thick gas-bearing sandstone.
出处
《石油天然气学报》
CAS
CSCD
2012年第1期58-62,166,共5页
Journal of Oil and Gas Technology
基金
国家自然科学基金项目(41074104)
国家"973"规划项目(2007CB209607)
关键词
低频阴影
时频分析
时频连续小波变换
衰减
low-frequency shadow
time-frequency analysis
time-frequency continuous wavelet transform
attenuation
