Аннотация:For downhole microseismic monitoring velocity model building, is a necessary step in the processing of
data and is considered one of the main factors controlling the accuracy of the hypocenter loсation. In this
paper we analyzed the possibility of using the weak anisotropy approximation to locate microseismic
events hypocenters. The use of weak anisotropy model reduces the computational cost, and it was shown
that for some cases it works well.