Source location estimation using single station three-component seismic date

Abstract : An experimental microseismic monitoring system composed of one three component station has been set up overlying the last iron mine in France. This experiment consisted of recording the seismic signals corresponding to the localised underground roof fall following the blasting of some small pillars 300 meters deep. The a priori knowledge of the position sources allows the application and validation of the seismic wave rotation technique to estimate the position of the microseismic events recorded at a single three component station. The method used is based on the calculation of the covariance matrix in a time window. However the length of this window significantly affects the precision of the calculations. The method used involves a new approach in which the length of the time window was optimised on the basis of the dominant frequency in the seismic signal. This article describes the approach to optimise the convergence process between numerical results and geometrical field assessment of experiment.