Development of an on-site Data Processing System-and-Application Soft for Reconnaissance Survey to Estimate Deep Geological Structure Using Microtremors

为使一种新的勘探技术能在任何时间、任何地点观测到具有相当稳定的频谱的地脉动，开发了简单、快速的数据处理基础程序和系统及应用软件。该技术利用7 ~ 10台地震仪组成的地震台阵观测，通过测量周期大于1 s的地震动中的面波（Rayleigh波）相速度，可以用横波速度分布的形式估计地下3 km的地质构造，数据处理包括估计功率谱和互谱。对于面波相速度的测量，频率-波数功率谱密度（F-K谱）的F-K方法，和空间自相关系数（SPAC系数）的SPAC方法计算从微动观测数据。用反演技术将面波的相速度反演为横波速度分布，所需的基本程序和应用软件都包括在新开发的应用软件“BIDOU”中。其中，对于结构模型，瑞利波或洛夫波的理论相速度也是可用的。根据横波速度随深度的变化规律，给出了地震资料的处理方法，并编制了相应的软件“DANMEN”。DANMEN程序可与相应的层位连接，用于在布置了台阵的场地下测定横波速度。这些程序和软件是一套完整的集成数据采集和处理的新技术，使用Widows 3.1在PC机上运行。这些功能强大的程序和软件已在50多个场地进行了测试，取得了良好的效果。

The fundamental programs and system-and-application softs have been developed for easy and quick data-processing for a new exploration technique which makes use of microtremors observable at any time in any place with a fairly stable spectrum. The technique can estimate geologic structure in a form of S-wave velocity distribution down to a depth of about 3km from measuring phase velocities of surface waves (Rayleigh waves) in microtremors with periods longer than Is, by observing with a seismic array consisting of 7 to l0 seismometers.The data processing in the technique includes estimating power spectra and cross spectra. For the measurement of phase velocities of surface waves, frequency-wavenumber power spectral densities (F-K spectra) for the F-K method, and spatial autocorrelation coefficients (SPAC coefficients) for the SPAC method are calculated from microtremor data observed. The phase velocities of surface waves are then inverted to an S-wave velocity distribution by an inversion technique.All the fundamental programs and application softs required with these data processing are included in the newly developed application soft 'BIDOU', in which the theoretical phase velocities of either Rayleigh or Love waves for a structure model are also available.A cross section of profile withspatially placed sites where seismometer arrays are deployed and geologic structures are determined is also given by S-wave velocity versus depth distribution, for which the soft program 'DANMEN' has been developed. The program 'DANMEN' can link with respective layrs for S-wave velocities determined under the sites where arrays are deployed.These developed programs and softs are fully integrated data acquisition and processing for a new exploration technique using microtremors, operating in Widows 3.1 on PC.These powerful programs and softs have been tested at more than 50 sites where good results have been obtained.