The Application of Seismic CT Technology in Urban Geological Survey

In order to successfully apply seismic computerized tomography(CT),at first,the author used cross-hole imaging method to get the first break travel time data.Then,on the processing basis of curved ray-tracing forward modeling based on shortest path method and inversion technique based on LSQR algorithm,combined with well logging data interpretation,the author got the cross-hole wave velocity distribution maps.Thus,within the scope of well control,the stratum structure and the foundation grouting effect were studied.Also,the locations and distributions of fracture tectonic belt and people shelter were gotten.This result shows that when seismic CT is used in urban environmental geological survey and evaluation and shallow engineering geological investigation,it can solve the complexity of formation lithology and structure and accurately predict the target environment.Seismic CT plays an important role in urban environmental geology research and in the construction of infrastructure and has important significance to promote the development of urban geophysical prospecting technique.