| Declustering of the northern Egypt earthquake catalog (1996–2022) using the epidemic‑type aftershock sequence (ETAS) model |
| Paper ID : 1050-ISCHU |
| Authors |
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Mariam Ramadan *1, Amin Esmail Khalil2, Hesham Eid Abdulhafiz3, Amir Ismail Abdelaziz4, Nouran Salama5 1Faculty of science, Helwan university. 2Faculty of science, Helwan University 3National Research Institute of Astronomy and Geophysics NRIAG 4Faculty of Science, Helwan University 5Faculty of Science, Helwan university. |
| Abstract |
| Earthquakes have the largest damaging effects among natural disasters. Efforts for reducing their effects have taken place for long time. The prediction of earthquakes was the main target, however the studies conducted were not successful. As a replacement, seismic hazard assessments were adopted to predict the levels of ground motion for the possible future large earthquakes. This approach is probabilistic in nature that rely on the earthquake catalog. Furthermore, the probabilistic model adopted is the Poissonian model, which assumes that events are independent on each other. Hence both foreshocks and aftershocks should be removed from the catalog. Seismic declustering, the process of removing foreshocks and aftershocks from an earthquake catalog is mandatory for the seismic hazard assessments. In this study, an earthquake catalog was declustered using the epidemic-type aftershock sequence (ETAS) model. ETAS is an R package for fitting the space-time ETAS model to an earthquake catalog, especially large datasets, using the stochastic declustering approach introduced by Zhuang et al. (2002). For this purpose, an earthquake catalog for the rectangular geographical region 26º-33º N and 30-36 E, which represents the northern part of Egypt, and period between 1996 and 2022 was extracted and processed. The results show that the high ability of the ETAS model to decluster the Egyptian earthquake catalog. Finally, the model was used to map the background seismicity of the study. The resulting catalog will be suitable for future seismic hazard estimation for the study area. |
| Keywords |
| Earthquakes , declustering |
| Status: Abstract Accepted (Poster Presentation) |