Development Of QT-based Interactive Software For Seismic Surface Wave Inversion

Seismic exploration based on surface wave is an important method to investigate shallow geological structure. Processing and inversion of multi-channel surface wave data provide shear wave velocity for inferring geological structure anomaly. It is a nonlinear equation between dispersion and velocity of medium. The dispersion picking from surface wave data and nonlinear inversion solution are essential processing workflows which need to be handled with visual software tools. Therefore,the visual software requirements include displaying and editing surface wave data,supporting interactive operation of picking dispersion curve and display a window of inversion results.In this paper, interactive software for seismic surface wave inversion is developed by using C++ and QT platform. It discusses requirements of the software,which include three parts: editing and displaying seismic data; processing surface wave and inversion; software interactive operation. Based on the above requirements,the software's functions are designed which contains interface design, algorithm design and interactive design. According to object-oriented design method, the object classes are designed: structure class, drawing class, file class and arithmetic class.Through the analysis and design, it is beneficial to program extension and promotion.What's more, it is convenient for software to be tested and maintained.The basic functions of the interactive software which has been developed are as follows:(1) Seismic data of SEGY format is realized to read and write. And the file header and trace header of SEGY data are processed; (2)in arithmetic class, add 2-Ddiscrete Fourier transform, surface wave dispersion calculation, genetic algorithm and other related algorithms to calculate; (3) design different widgets to draw x-t data,f-k data, f-v data, v-h data and error data of seismic surface wave, and show the different map before and after inversion ; (4)some basis interactive functions in display window are includes: zoom in or zoom out, mouse dragging, interactive picking using the mouse and keyboard. (5) In addition, some self-defined dialog boxes supporting parameter communication, such as seismic shot number. This software is developed on QT creator platform and debug with VC platform. VC and QT platform is an important tool to achieve its interactive picking software. A field surface wave is run reliably on this software,which shows my design is achieved well.Some functions are tested as dynamic display,picking surface wave dispersion,and a good interaction. But it is poor software for surface wave process, and more programs will be added and improved.