Abstract: To improve the accuracy of microseismic source location, the application scope, the advantages and disadvantages of traditional and improvement algorithms in locating solving were comparatively analyzed based on the simulation experiment. The influence of unknown variables, sensors’ density and P wave velocity on the location algorithms were studied respectively. Based on the advantages of the simplex and the global convergence characteristics of the simulated annealing, it was proposed that taking the steady simulated annealing-simplex algorithm located the microseism. The study shows that this algorithm is a simple estimation in advance by steady arithmetic without directly searching for the seismogenic moment. The searching steps can be greatly reduced and the location accuracy and convergence velocity can be improved. So the microseismic focus can be effectively located with less sensors without being affected by the initial velocity. Taking the artificial blasting location test experiment of a mine as an example, the errors of both the location accuracy and objective function for the simulated annealing-simplex, the steady simulated annealing-simplex and the other algorithms were specially analyzed. It is widely believed that applying the nonlinear least square algorithm can get reliable results when there are more sensors and better information of P wave. The errors of three-dimensional location and objective function of the other location algorithms are basically the same. But the objective function error of the steady simulated annealing-simplex algorithm is the minimum; and the stability is the best. So this algorithm with higher reliability and stability has obvious advantages; and it can be widely used for the microseismic location in mines.

Key words: microseisms, three-dimensional locating, nonlinear least square, simplex, simulated annealing, steady estimation