时频分析——薄互层结构研究的新途径

TIME-FREQUENCY ANALYSIS -A New Way for Thin Interbeds Examination

大庆油田物探公司研究所

Research Instotide of Geophysical Prospecting Co., Doqing Oilfield

时频分析是根据地震响应的时频变化规律来研究薄互层结构的一种新方法.本文论述了时频分析的基本思想,讨论了时频分析资料处理中地震子波、时窗长度、滑动步长等处理参数,以及多次波、吸收衰减等对时频分析结果的影响,采用理论模型建立了不同类型沉积结构的时频响应,在对比分析的基础上讨论了时频分析的基本解释方法。经松辽盆地北部薄层砂岩结构时频分析基本的初步应用,已见到一定的效果。

TIME-FREQUENCY ANALYSIS is a new technique for thin interbeds examination. The technique is based on the ground of time-frequency variation of seismic response. In this paper,the fundamental ideas about the time-frequency analysis was expounded,effects resulted from the seismic wavelet,the window length,the step length as well as the other processing parameters were discussed. Also discussed were the effects of the multiple,the absorption and the attenuation. The time-frequency responses for sedimentary texture of different types were developed by means of the theoretical model. The principle and technique for data interpretation were delineated by comparision. Application shows that the thin interbeds were distinguished very well In northern Songliao basin.