We propose a new method for detecting seismic events recorded by an array of receivers. The method uses an approximate moveout of a known master event to stack the normalized traces containing only the instantaneous phase. We show that the instantaneous phase stack is a stationary Gaussian process, which makes event detection a classical statistical problem of finding outliers in a sample of multidimensional Gaussian vectors. Application to Groningen field data shows a very good performance of our detector.
