倾斜边坡多道面波分析中的最小偏移距估计方法

The nearest offset distance estimation method for multi-channel analysis of surface waves in slope

  • 摘要: 为减小倾斜边坡中能量较强的近场体波对面波识别的干扰,确保多道面波分析方法接收到的瑞雷波分量具有较强的能量,本文通过分析地下震源在倾斜边坡产生的瑞雷波及其传播规律,基于几何地震学提出了在倾斜地表生成瑞雷波的最小偏移距的经验公式,建立了界面起伏的层状倾斜边坡模型,从而获得模拟共炮点记录,并将基于共炮点记录得到的地表质点运动轨迹、频散计算结果与理论值、估计值进行了对比,结果显示四者具有较强的相关性,由此表明本文提出的最小偏移距估计方法对层状倾斜边坡地表的面波勘探具有一定的指导意义。

     

    Abstract: In order to reduce the interference of energetic near-field body waves to surface wave identification and to ensure Rayleigh wave components with strong energy to be collected by multi-channel analysis of surface waves (MASW) method in the slope, this study firstly analyzed the Rayleigh wave propagation mechanism induced by the underground passive source on the slope. Secondly, based on geometric seismology, an empirical formula for the minimum offset of the Rayleigh wave generated on the sloping surface is proposed, and the layered slope with undulating interface is established so as to obtain the simulated common shot point records. Then by comparing the surface particle motion trajectory and dispersion calculation results obtained from the common shot point records with the theoretical values and estimated values, the results show that the four physical quantities have a strong correlation, which indicates that the proposed minimum offset estimation method in this study can be adopted to guide surface wave exploration of layered slopes.

     

/

返回文章
返回