Based on the formula deduced by Aleksandrowski for calculating pitch direction of fault slip data

an improved method for determination of tectonic stress tensor was put forward. A method for back analysis of tectonic stress field was deduced by least square method based on the relation between tectonic stress with pitch direction of fault slip data in different stress ratio values. At last

the calculating process was deduced by Matlab program. The fault slip data were obtained in the Wushan mining region

Jiangxi province. On this basis

by the improved method of inversion of fault slip data

the parameters of tectonic stress tensor in mine region were determined. The tectonic stress field in this area since Late Jurassic was obtained

by comparing the faults with the average stress field of the region obtained from focal mechanism solutions and studying distribution of the strike-slip faults and the tectonic setting of this area. It is indicated that the tectonic stress field in this area has better stability since Late Jurassic. The progress of solving tectonic stress tensor and the application of the improved method show that

comparing with the graphical instrument method put forward by Aleksandrowski and the method for back analysis by Etchecopar

the method is simple and more feasible

and the focal mechanism solution is reasonable.