A method of analyzing measured microseismic events obtained from monitoring induced hydraulic fracturing of underground geological formations, the method involving (a) postulate a geomechanical model for the region bounding the microseismic events, the model including the parameters vertical stress, reservoir pore pressure, minimum horizontal stress and the orthogonal horizontal stress, (b) select a microseismic event and (c) for the selected microseismic event assume an associated slippage plane with a postulated orientation, (d) apply the geomechanical model to the postulated orientation to determine the resulting shear stress and normal stress applied to the postulated orientation, (e) repeat steps (c) and (d) to produce a number of postulated slippage planes each with their own shear stress and normal stress attributable to them, (f) select the fracture plane having the highest ratio of shear stress to normal stress as being the fracture plane most likely to be representative of a real slippage plane consistent with the geomechanical model, (g) repeat steps (b) to (f) to analyze a number of microseismic events to generate a slippage plane most likely to be representative of a real slippage plane for each microseismic event is provided.