Abstract: Debris flow over the world always moves in manner of intermittent surges, which is the most conspicuous appearance in Jiangjia Gully (JJG), Yunnan. More than fifty years of real-time observations of living debris flows in JJG have achieved a huge dataset of parameters concerning more than 10 000 surges, from which derive several fundamental features of the surge sequences: probability distribution of the interval, fluctuation and distribution of discharge, decay of the sequence, Hurst index and surge concentration in space and time. All these characteristics suggest that the surge sequence is a systemic behavior of some underlying dynamics and hints at some nonlinear dynamical mechanism of debris flow formation and evolution.