title: Scaling of seismic memory with earthquake size.
abstract: It has been observed that discrete earthquake events possess memory, i.e., that events occurring in a particular location are dependent on the history of that location. We conduct an analysis to see whether continuous real-time data also display a similar memory and, if so, whether such autocorrelations depend on the size of earthquakes within close spatiotemporal proximity. We analyze the seismic wave form database recorded by 64 stations in Japan, including the 2011 "Great East Japan Earthquake," one of the five most powerful earthquakes ever recorded, which resulted in a tsunami and devastating nuclear accidents. We explore the question of seismic memory through use of mean conditional intervals and detrended fluctuation analysis (DFA). We find that the wave form sign series show power-law anticorrelations while the interval series show power-law correlations. We find size dependence in earthquake autocorrelations: as the earthquake size increases, both of these correlation behaviors strengthen. We also find that the DFA scaling exponent α has no dependence on the earthquake hypocenter depth or epicentral distance.
authors.affiliation: Department of Environmental Sciences, Tokyo University of Information Sciences, Chiba 265-8501, Japan.
authors.forename: Zeyu
authors.initials: Z
authors.lastname: Zheng
authors.forename: Kazuko
authors.initials: K
authors.lastname: Yamasaki
authors.forename: Joel
authors.initials: J
authors.lastname: Tenenbaum
authors.forename: Boris
authors.initials: B
authors.lastname: Podobnik
authors.forename: Yoshiyasu
authors.initials: Y
authors.lastname: Tamura
authors.forename: H Eugene
authors.initials: HE
authors.lastname: Stanley
mesh_terms: D003198:Computer Simulation; D055866:Earthquakes / Q000706:statistics & numerical data*; D005544:Forecasting / Q000379:methods*; D015233:Models, Statistical