Acta Geophysica

, Volume 66, Issue 6, pp 1359–1373 | Cite as

Declustering of Iran earthquake catalog (1983–2017) using the epidemic-type aftershock sequence (ETAS) model

  • Nader Davoudi
  • Hamid Reza Tavakoli
  • Mehdi Zare
  • Abdollah Jalilian
Research Article - Solid Earth Sciences


The main goal of this article is to decluster Iranian plateau seismic catalog by the epidemic-type aftershock sequence (ETAS) model and compare the results with some older methods. For this purpose, Iranian plateau bounded in 24°–42°N and 43°–66°E is subdivided into three major tectonic zones: (1) North of Iran (2) Zagros (3) East of Iran. The extracted earthquake catalog had a total of 6034 earthquakes (Mw > 4) in the time span 1983–2017. The ETAS model is an accepted stochastic approach for seismic evaluation and declustering earthquake catalogs. However, this model has not yet been used to decluster the seismic catalog of Iran. Until now, traditional methods like the Gardner and Knopoff space–time window method and the Reasenberg link-based method have been used in most studies for declustering Iran earthquake catalog. Finally, the results of declustering by the ETAS model are compared with result of Gardner and Knopoff (Bull Seismol Soc Am 64(5):1363–1367, 1974), Uhrhammer (Earthq Notes 57(1):21, 1986), Gruenthal (pers. comm.) and Reasenberg (Geophys Res 90:5479–5495, 1985) declustering methods. The overall conclusion is difficult, but the results confirm the high ability of the ETAS model for declustering Iranian earthquake catalog. Use of the ETAS model is still in its early steps in Iranian seismological researches, and more parametric studies are needed.


Declustering Earthquake catalog Seismotectonic provinces of Iran Windowing methods ETAS model 







Gardner and Knopoff


Gruenthal method


Epidemic-type aftershock sequence model



The authors acknowledge the funding support of Babol Noshirvani University of Technology through Grant No. BUT/388011/97. We wish to appreciate Mohammad Shahvar for his help in providing the earthquake catalog and magnitude conversation relations used in this article.

Authors’ contributions

HRT proposed the initial idea and guided us in the analysis. ND analyzed the data completed all experiments and wrote the manuscript. MZ directed us to create a seismic catalog and seismic zoning. AJ developed the ETAS model code. All authors read and approved the final manuscript.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Institute of Geophysics, Polish Academy of Sciences & Polish Academy of Sciences 2018

Authors and Affiliations

  1. 1.Department of Civil EngineeringBabol Noshirvani University of TechnologyBabolIran
  2. 2.Department of SeismologyInternational Institute of Earthquake Engineering and SeismologyTehranIran
  3. 3.Department of StatisticsRazi UniversityKermanshahIran

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