Correlations of the seismic activity monitored in three subduction zones belonging to Cocos plate by using the visibility graph method.

Abstract

The temporal sequences of magnitudes recorded in seismic active zones exhibit complex behavior which is associated with the wide diversity of scales of fractures sizes when an earthquake on the Earth’s crust occurs. Earthquakes can be considered to be nearly, or even critical phenomena exhibiting dynamic phase transitions, where a mainshock is the beginning of a new phase. Near the critical point is where phase transition (order-disorder) occurs, and scaling laws with long-range order correlations are produced, so that the complexity of seismicity allows earthquakes to be characterized by a more diverse and riche phenomenology. In the last years, the ideas linked to nonlinear time series analysis and complex network theory have been related. Among those ideas,  the visibility graph (VG) method has been applied to the study different complex phenomena. One of the characteristics of this method is its ability to capture dynamic properties, such as non-trivial correlations in nonstationary time series, without introducing elaborate algorithms such as detrending. Seismic processes have been of great interest and their complete understanding is still an open problem. In this work we use the VG method to study the temporal correlations in the seismic sequences monitored in three regions of the subduction zone belonging to the Cocos plate. Our analysis allows estimate persistence and the temporal correlations in the seismic activity monitored in Michoacan State, Mexican Flat Slab and Tehuantepec Isthmus, showing differences in all three.