In this article, we present a parallel algorithm for determining the type of a seismic source from seismic observational data using the Time-Reversal Mirror (TRM) method. This problem has a wide range of applications, including virtual source modelling, non-destructive testing of materials and engineering structures, and earthquake source location. Our proposed algorithm is motivated by the need to retrieve not only the location but also the type of the source. To achieve this, we use numerical simulations based on a three-dimensional model of a dynamic elasticity theory and a finite-difference scheme on staggered meshes. To parallelize the algorithm, we use MPI functions and the domain decomposition approach. To improve the efficiency, we rely on techniques such as data exchange in the computational background and the non-blocking MPI functions. We present and discuss the results obtained from our numerical simulations, which demonstrate the possibility of determining the type of seismic source. The proposed algorithm can be used in a variety of scientific and engineering applications, particularly in earthquake source location and non-destructive testing.