Synthetic earthquake catalogs simulating seismic activity in the Corinth Gulf, Greece, fault system

Abstract

The characteristic earthquake hypothesis is the basis of time-dependent modeling of earthquake recurrence on major faults. However, the characteristic earthquake hypothesis is not strongly supported by observational data. Few fault segments have long historical or paleoseismic records of individually dated ruptures, and when data and parameter uncertainties are allowed for, the form of the recurrence distribution is difficult to establish. This is the case, for instance, of the Corinth Gulf Fault System (CGFS), for which documents about strong earthquakes exist for at least 2000 years, although they can be considered complete for M ≥ 6.0 only for the latest 300 years, during which only few characteristic earthquakes are reported for individual fault segments. The use of a physics-based earthquake simulator has allowed the production of catalogs lasting 100,000 years and containing more than 500,000 events of magnitudes ≥ 4.0. The main features of our simulation algorithm are (1) an average slip rate released by earthquakes for every single segment in the investigated fault system, (2) heuristic procedures for rupture growth and stop, leading to a self-organized earthquake magnitude distribution, (3) the interaction between earthquake sources, and (4) the effect of minor earthquakes in redistributing stress. The application of our simulation algorithm to the CGFS has shown realistic features in time, space, and magnitude behavior of the seismicity. These features include long-term periodicity of strong earthquakes, short-term clustering of both strong and smaller events, and a realistic earthquake magnitude distribution departing from the Gutenberg-Richter distribution in the higher-magnitude range.

Characteristic Earthquake Magnitude Frequency Distributions on Faults Calculated From Consensus Data in California

“…The second independent method we apply is a physics‐based earthquake simulator (Console et al, , ) where the seismogenic system is modeled by rectangular fault sections. Each section is composed of many square cells of size set to the minimum earthquake rupture of interest ( M = 5.0 in this case).…”

Repeating earthquakes in western Corinth Gulf (Greece): implications for aseismic slip near locked faults

“…1) have struck the broader area of western Corinth Gulf during the instrumental era and caused severe damage in several cities (Papazachos & Papazachou 2003;Makropoulos et al 2012). The assessment of the hazard emerging from these frequent strong events has been the target of numerous studies among them being recently the approximation with synthetic catalogues (Console et al 2015;Mangira et al 2017). The last strong earthquake with M = 6.5 occurred on 1995 June 15 and was associated with the Aigion fault (Bernard et al 1997).…”

Spacing and strength of active continental strike-slip faults

“…Constraining fault strength is critical in modeling continental deformation (Bird and Kong, 1994) and earthquake mechanics (Console et al, 2015), and this work provides an additional method of estimating this critical parameter.…”