基于主被动源频散曲线拼接策略的面波频散曲线反演研究

Surface Wave Dispersion Curve Inversion Based on Active and Passive Source Dispersion Curve Splicing Strategy

面波勘探是浅地表勘查的主要方法之一,传统的主动源面波方法探测深度通常在30 m以浅,且在噪声干扰复杂的城市环境中作用严重受限;被动源面波正是利用背景噪声为信号源,探测深度大,但对浅层介质分辨能力较差。为此,提出一种主动源、被动源面波数据处理方法,兼顾勘探深度和浅层分辨率。首先对主动源和被动源数据的频散曲线进行拼接,从而获得更宽频带的多阶频散曲线。然后采用数值模拟并反演处理,验证主被动面波频散曲线拼接策略的有效性。通过实测数据处理,对比分析了主动源方法和拼接策略的反演效果,证明了主被动源频散曲线拼接策略能有效提高反演结果精确度。该策略解决了单一震源能量频带有限对反演结果造成的影响,为面波勘探提供了新的手段。

Surface wave exploration is one of the main methods of shallow surface exploration.The traditional active source surface wave method usually probes at a depth of 30m,and its effect is severely limited in the urban environment with complex noise interference.Passive surface wave uses background noise as signal source,which has large detection depth but poor resolution to shallow medium.This paper proposes a surface wave data processing method with both active and passive sources,which takes into account exploration depth and shallow resolution.Firstly,the dispersion curves of active and passive source data are splicing to obtain a broader multi-order dispersion curve.Secondly,Numerical simulation and inversion were used to verify the validity of the splicing strategy of active and passive surface wave dispersion curves.Through the measured data processing,the inversion effect of the active source method and the splicing strategy is compared and analyzed.It is proved that the splicing strategy of the active and passive source dispersion curves can effectively improve the accuracy of the inversion results.This strategy solves the problem caused by the limited energy band of a single source and provides a new method for surface wave exploration.