影响地震数据相位特征的因素分析

Analysis of influence factors on phase characteristics of seismic data

(1.中国石油大学（华东）地球科学与技术学院,山东青岛266555；2.中国石油化工股份有限公司胜利油田分公司物探研究院,山东东营257012)

Sun Chengyu, China University of Petroleum,Qingdao 266555,China

地震波在传播过程中会受到许多因素的影响,其相位会发生改变,处理过程也会使地震记录的相位发生不同程度的畸变,地震波的波形会发
生改变。基于影响相位变化的主要因素建立了典型模型,通过波场正演模拟,分析与测试了粘弹性介质、地层厚度、韵律型地层、递变型地层和
弯曲界面对地震波相位的影响。正演模拟结果表明，在Q值较小的情况下, Q值越小相位越滞后；薄层厚度大于1/4波长时,薄层越厚相位越滞后
；韵律型和递变型结构的层序体厚度越大,相位越滞后；背斜界面与水平界面相比相位稍有超前,而向斜界面的相位则略微滞后,且向斜界面的相
位变化幅度较背斜界面的相位变化幅度小。

Seismic wave is affected by many factors during the propagation,which makes the phase change.In addition,data processing also
distorts the phase of seismic record to varying degree and changes the waveform of seismic wave.Typical models were
established based on the main factors which impact the phase of seismic wave.By forward modeling,the impact of some factors
on the phase of seismic wave were analyzed and tested,including viscoelastic medium formation thickness,rhythm layer,and
progressive layers and bending interface.Several conclusions were obtained from the forward modeling:①when the Q value is
small,the phase becomes more delayed as Q decreases;②when the thickness of the thin layer is bigger than 1/4 wavelength,the
phase becomes more delayed as the thickness increases;③the phase becomes more delayed as the thickness of the sequence in
rhythm and progressive layer increases;④compared with horizontal interface,the phase of anticline interface is slightly
advanced while the phase of the syncline interface is slightly delayed,and the phase alternation amplitude of the syncline
interface is smaller than that of the anticline interface.

10.3969/j.issn.1000-1441.2001.05.004