Cross-well Seismic Computer Tomography And Its Aplication

Cross-well seismic computer tomography is due to inspire and receivingunderground, compare to the ground seismic method has overcome the effect ofsurface layer, close to the target detection, energy transmission distance is short, canobtain higher resolution and the SNR of seismic signals, etc. and can offer finestructure and content of lithological changes visual image of detect purpose. Firstlythis technology rapid develop in the structure of the earth research and oil gas deposits,all kinds of theory method has been matured. Then the technology constantlypenetrate to the engineering field, widely used in engineering geological investigationand civil engineering quality test, etc. has good result to all sorts of engineeringtesting of abnormal body, such as collapse columns, fissures, cracks, fracture zone,soft interlayer, empty or unknown underground structures and so on.This dissertation based on Radon transformation and its inverse transform, whichis mathematical basis of computer tomography. Program to realize its positive andnegative transformation, and through the seismic model to verify it. Mainly introduceseveral methods of tomographic modeling and its inversion. Modeling methodincluding flat ray tracing and curved ray tracing, program and realize smallest traveltime ray tracing method which belong to curved ray tracing, and improve the speednetwork structure model to obtain higher precision of ray tracing. The inversionmethod mainly introduces simultaneous iterative reconstruction method (SIRT) andorthogonal decomposition least squares decomposition method (LSQR), using thegiven model realize two algorithm. Introduce cross-well seismic tomography dataacquisition and processing and interpretation conventional technology. Finallyintroduce the application of seismic computer tomography in the engineering qualitytest combined with engineering example, and obtain good effect.