Spatiotemporal Comparison of Declustered Catalogs of Earthquakes in Turkey

Abstract

In earthquake seismology, an independent earthquake can produce a set of clusters having fore- and/or aftershocks. The main purpose of seismicity declustering is to refine a given earthquake catalog in order to retain independent events. The goal of retention of independent events by only declustering is a crucial benchmark for most of the mainshock-based analysis in seismology. In the present article, we used a re-updated unified earthquake catalog of Turkey and obtained several declustered catalogs applying different declustering methods. To compare the performance of applied declustering methods, each declustered catalog was then examined by simulation envelopes and Monte Carlo tests using some summary statistics for temporal and spatial point patterns. We found that the declustering method of Zhuang et al. (2002) based on the Epidemic Type Aftershock Sequence (ETAS) model, original version, and particularly Grunthal’s variant of the Gardner and Knopoff (1974) method seemed to be most successful in finding and removing clusters in space and time for the earthquake catalog of Turkey examined.