Study On Automatic Micro-seismic Signal Detection And Inversion Method Of Source-scanning DIRECT

The micro-seismic monitoring technology is based on the theory of acoustic emission and Seismology as a new geophysical technology, which is mainly used in the field of oil gas field development, mine geological disaster monitoring and engineering construction and site selection. This thesis is based on the research of the data of the micro-seismic monitoring and the related research work, and focusing on the research of the inversion method of the source-scanning DIRECT algorithm. The theory study and algorithm program implementation of the method are complished for the automatic detection(event identification and travel time parameters pickup)of the micro-seismic forward simulation and the micro-seismic signal. And the tasks of field measurement and engineering application are complished.The micro-seismic numerical simulation of two points fast ray tracing is realized by programming. The program included the subroutine of three-dimensional horizontal layered medium ray tracing, micro-seismic record three component synthesis and noise adding. A similarity criterion is based on the signal of the same micro-seismic event in each record and the use of wave cross-correlation method, and the program of the automatic detection method for the micro-seismic signal is accomplished. The correctness and efficiency of the program are verified by the ground monitoring, underground(vertical wells, inclined wells, curved wells)monitoring and ground-underground monitoring modes.In this thesis, the DIRECT algorithm is deeply analyzed and tracked. The core technology of this method is the identification of search space and potential optimal space. Based on this, the design of the source-scanning parameters of the DIRECT algorithm is further realized. Theoretical and experimental results of the inversion of micro-seismic data show that the algorithm converges faster and the inversion precision is higher. Monitoring the ground, underground(vertical wells, inclined wells and curved wells) and well monitoring multiple model forward test verify the correctness and efficiency of the forward modeling program In addition, In this thesis, the surface near horizontal surface is specially noted for the monitoring of micro-seismic situation, The accuracy of Z coordinates(depth and elevation) of source location results is usually not higher than the accuracy of X and Y coordinates. In this paper, the technical scheme of monitoring receiver station in the fluctuation terrain is Proposed, by which the quality of the inversion of the ground micro-seismic monitoring of mountain environment is not improved greatly. This scheme is extended to the ground receiver site and receiver site under the condition of cone hole. On the basis of the above work, the actual micro-seismic data are processed, and the better results are obtained in this thesis.