Probabilistic Seismic‐Hazard Assessment for Eritrea

Berhe Goitom, Maximilian Werner, Katsu Goda, J M Kendall, James Hammond, Ghebrebrhan Ogubazghi, Clive Oppenheimer, Agnes Helmstetter, Derek Keir, Finnigan Illsley-Kemp

Research output: Contribution to journalArticle (Academic Journal)

5 Citations (Scopus)
321 Downloads (Pure)

Abstract

To date little is known about seismic hazard in Eritrea, despite its location
in a volcanically and tectonically active region, and the gathering pace of major infrastructure projects. In response, we report the findings of a comprehensive probabilistic seismic-hazard assessment for Eritrea and adjacent areas. Seismic source and groundmotion models are constructed separately; we use an adaptive spatiotemporal smoothing method to map expected patterns of seismicity. To construct a consistent earthquake catalog from different data sets, we use orthogonal regression to convert and unify different magnitude scales. A sensitivity analysis of the different input parameters helps constrain them and disaggregation of site-specific hazard estimates yields insights into the relative contribution from seismic sources of different magnitudes and distances.
The results highlight seismic hazard in proximity to the Red Sea, Gulf of Aden, Afar depression, and along the boundaries of the Danakil microplate. We estimate a 10% chance over 50 years of observing pseudospectral accelerations (PSAs) at 0.2 s exceeding 0:16g in the port city of Massawa (population ∼32;000) and the town of Bada (population ∼4000). For the capital, Asmara (population ∼520;000), we calculate a PSA of 0:11g at 0.2 s. Compared with previous studies, our results provide greater spatial resolution, use more recent ground-motion models, and benefit from a smoothed seismicity method. Our aims are to stimulate further studies and contribute to the safe development of the region in light of its exposure to seismic hazards.
Original languageEnglish
Pages (from-to)1478-1494
Number of pages17
JournalBulletin of the Seismological Society of America
Volume107
Issue number3
Early online date21 Mar 2017
DOIs
Publication statusPublished - 21 Jun 2017

Keywords

  • Seismic hazard
  • East Africa
  • Eritrea
  • Adaptive smoothing
  • Disaggregation

Fingerprint Dive into the research topics of 'Probabilistic Seismic‐Hazard Assessment for Eritrea'. Together they form a unique fingerprint.

  • Cite this

    Goitom, B., Werner, M., Goda, K., Kendall, J. M., Hammond, J., Ogubazghi, G., Oppenheimer, C., Helmstetter, A., Keir, D., & Illsley-Kemp, F. (2017). Probabilistic Seismic‐Hazard Assessment for Eritrea. Bulletin of the Seismological Society of America, 107(3), 1478-1494. https://doi.org/10.1785/0120160210