Automatic Phase Detection in Seismic Data using the Discrete Wavelet Transform

Seismic data consist of traces, which contain information about a seismic event, but in some period of time the traces may be just noise. A trace which contains seismic information, is called a seismic signal. Seismic signals consist of several typically short energy bursts, called phases, exhibiting several patterns in terms of dominant frequency, amplitude and polarisation. Amongst others, a significant phase is the S-phase. We present a fast algorithm to detect the S-phase in a three-component seismic signal. This new approach is a combination of traditional S-phase detection methods from seismology and the discrete wavelet transform. Stability and correctness of the algorithm will be proved and results will be presented to demonstrate the algorithm. 1991 Mathematics Subject Classification: 42C15, 65G99, 86A15, 94A12, 94A13.