基于频率域多阶微分融合的地震频带拓宽方法研究  

Seismic bandwidth broadening method based on multi-order differential fusion in frequency domain

作　　者：郭欣[1] 雍学善[2,3] 高建虎[2,3] 刘伟方[2,3] 李胜军[2] 

机构地区：[1]中国石油天然气股份有限公司勘探开发研究院,北京100083 [2]中国石油天然气股份有限公司勘探开发研究院西北分院,甘肃兰州730020 [3]中国石油天然气集团公司油藏描述重点实验室,甘肃兰州730020

出　　处：《石油物探》2016年第2期271-279,共9页Geophysical Prospecting For Petroleum

基　　金：国家科技重大专项"大型油气田与煤层气开发"专题(2016ZX05007-006)资助~~

摘　　要：针对地震资料频带较窄的问题,提出了一种基于频率域多阶微分融合的地震频带拓宽方法,该方法利用微分运算可揭示信号微观特征的性质来拓展高频信息。微分算子在振幅谱上与频率呈平稳的递增关系,微分阶数大小决定了信号高频的提高程度。在测井反射系数振幅谱低频趋势的约束下,将不同阶微分提取的信息进行多次迭代融合,并将其变换到时间域,获得了宽频的地震记录,其高截频可以提升1倍左右,有效地降低了地震子波带限的影响。利用该方法对薄互层数学模型、尖灭体物理模型和实际地震数据进行了试处理,均取得了较好的效果,验证了本方法对于拓展地震资料频带的可行性及有效性。Due to the limited bandwidth of seismic wavelet,the information outside of the wavelet bandwidth is difficult to be distinguished and identified,which leads to the low resolution.To the issue,we present a multi-order differential fusion method in frequency domain to broaden the seismic bandwidth.Differential operators have linear features of increasing monotonically and can improve high frequency and suppress low frequency of signals,namely it has the attribute of frequency spectral decomposition and higher differential order represents higher frequency.We can extract the reflection coefficient from logging data and calculate the low frequency change trend of its amplitude spectrum,which are non-white noise components.Then we add up the differential signal through multiple iterations under the constraint of the non-white noise components.A new broadband seismic record is achieved after back to the time domain from the frequency domain,which has the same trend with the spectrum of reflection coefficient and its high cut-off frequency can be doubled,so it can effectively weaken the influence of the limited bandwidth of the seismic wavelet.It demonstrates that this method can broaden the bandwidth well and improve the resolution of seismic data through the test processing of thin interbedded mathematical model,physical model with pinchout bodies and real seismic data.

关 键 词：多阶微分 频率域 迭代融合 拓宽频带 经验模态分解 

分 类 号：P631[天文地球—地质矿产勘探]