在我国陆地石油勘探中，炸药震源依然是地震勘探的主要震源，炸药爆炸后会产生不同的分区，包括空腔、过渡区和弹性区。如今对地震子波产生机理的分析主要是基于等效球腔模型，忽略了过渡区对波传播特征的影响。为了定性描述过渡区的岩石破碎和永久形变对地震波传播特征的影响，将模型简化为粘弹性介质。这里在 Kelvin 粘弹性模型基础上推导了地震波传播的相速度和品质因子 Q 的表达式，并对 Kelvin 粘弹性模型进行数值模拟，从振幅、相位及频率的角度，分析品质因子 Q 对地震波传播特征的影响。结果表明，地震波在粘弹性介质中传播时，振幅、频率及相位特征是有变化的，这为研究炸药震源激发产生地震子波的机理提供了理论方向，为实际介质中的地震记录特征分析提供了理论基础，同时对补偿粘滞性因素的影响、提高地震资料的品质具有重要的实际意义。%In our country ,an explosive source is the most commonly used excitation source in seismic exploration .Different partitions will be produced after the explosive ,include cavity ,transition zone and elastic zone .So far ,to study how the seismic wave produced ,the most commonly way is called “equivalent spherical cavity” ,which ignores the impact of the transition zone . To descript the influence of cruse and permanent deformation of the transition area to the seismic wave qualitatively ,the model can be simplified as viscoelastic model .In this paper ,we deduce the phase velocity and the expression of Q based on the Kelvin viscoelastic model ,then we use Kelvin viscoelastic model to forward modeling algorithm ,and analyze the impact of quality factor Q on the basic frequency ,amplitude and phase of seismic wave .The results show that the amplitude ,frequency and phase of seismic wave are changed in the transition area ,which provides a theoretical direction for the analysis of production of seismic wavelet ,and also provides a theoretical basis for the analysis of seismic data collected in the actual medium .At the same time ,it provides a meaningful actual value for the compensation of the influence on the viscosity factor and improving the quality of seismic data .
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