Real-Time Ground-Motion Analysis: Distinguishing P and S Arrivals in a Noisy Environment

Particle motion analysis by recursive singular value decomposition is used to distinguish basic seismic phases online from a stream of three-component data with sample-to-sample resolution. This article describes a real-time method for implementation on a three-component seismometer with limited computing resources. It is proposed that the use of instruments equipped with the suggested phase detecting capabilities would provide the basic components of an earthquake or a tsunami early warning system.