Scale invariance of shallow seismicity and the prognostic signatures of earthquakes

The results of seismic investigations based on methods of the theory of nonequilibrium processes and self-similarity theory have shown that a shallow earthquake can be treated as a critical transition that occurs during the evolution of a nonequilibrium seismogenic system and is preceded by phenomena such as the scale invariance of spatiotemporal seismic structures. The implication is that seismicity can be interpreted as a purely multifractal process. Modeling the focal domain as a fractal cluster of microcracks allows formulating the prognostic signatures of earthquakes actually observed in seismic data. Seismic scaling permits monitoring the state of a seismogenic system as it approaches instability.