estimate azimuth using three component seismic data from a single station, which can be used for earthquake location using a single station
Reference: Roberts, R. G., Christoffersson, A. and Cassidy, F. (1989), Real-Time Event Detection, Phase Identification and Source Location Estimation Using Single Station Three-Component Seismic Data. Geophysical Journal International, 97: 471–480. doi:10.1111/j.1365-246X.1989.tb00517.x