Development of a measurement techniques of coherent waves by a downhole double three compnent seismic detector

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1.Application to super resolution mapping : We investigated a method to use crossvariance matrix from upper and lower detector in frequency domain for precise detection of polarization of P wave. It has been revealed that effect of uncorrelated noise is effectively suppressed by this method.2.Application to AE reflection method : Software for three dimensional TFC method, where coherency of hodogrmas is evaluated, was developed. Reflectors at Kakkonda geothermal field was successfully imaged by this method.3.Application to drill bit reflection method : The TFC method was used in the analysis existing data sets and the effectiveness of this method was investigated.4.Application to cross hole measurement : Field experiments to detect coherent waves from pressurized fracture were made in Tohoku University Higashi Hachimantai Field, Iwate. Some coherent component appeared in the coherence index associated with water injection, although interpretation of origin and characteristics of thie wave has not done yet.