Please use this identifier to cite or link to this item:
http://hdl.handle.net/2122/1225
DC Field | Value | Language |
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dc.contributor.authorall | Badawy, A.; National Research Institute of Astronomy and Geophysics, Helwan, Cairo, Egypt | en |
dc.date.accessioned | 2006-07-05T08:04:10Z | en |
dc.date.available | 2006-07-05T08:04:10Z | en |
dc.date.issued | 2001-06 | en |
dc.identifier.uri | http://hdl.handle.net/2122/1225 | en |
dc.description.abstract | The present-day stress field has been investigated by the analysis of the directions of maximum horizontal stress (ó 1 ) inferred from earthquake focal mechanisms and borehole breakouts in Egypt. The results indicate that strike-slip and normal faulting movements characterize the majority of the earthquake focal mechanisms; only a few events are of reverse faulting type. The analysis of 35 mechanisms suggests that the present-day stress field in Southern Egypt is dominated by a strike-slip stress regime (SS) and it is mainly transtensional (NS: normal faulting with strike-slip component) in Northern Egypt. The orientation of P-axes reflects that the maximum horizontal stress (ó 1) in Southern Egypt is uniform and aligned to nearly E-W direction while in Northern Egypt it is aligned with an even mix of NW-SE and nearly E-W compression. Along the Gulf of Aqaba, the southern part of the Dead Sea Fault (DSF), the focal mechanism solutions indicate that the maximum horizontal stress is presently oriented NW-SE, corresponding to a strike-slip mechanism in concert with geological evidence. More detailed investigations have been performed for the Gulf of Suez. We compare our results to the near-surface stress measurements from borehole breakouts to see if there is a change in orientations with depth. Shallow stress directions derived from borehole breakouts are not consistent with the deep stress directions derived from earthquakes focal mechanisms. About 73% of 30 borehole breakouts measurements indicate NW-SE alignment of the maximum horizontal stress and 27% are ENE-WSW. The direction of ó 1 inferred from the focal mechanism solutions is changing from NE-SW to ENE-WSW. Therefore, at least in this area, the stress direction is not constant throughout the crust. | en |
dc.format.extent | 4974668 bytes | en |
dc.format.mimetype | application/pdf | en |
dc.language.iso | English | en |
dc.relation.ispartofseries | 3/44 (2001) | en |
dc.subject | stress field | en |
dc.subject | focal mechanisms | en |
dc.subject | break-outs | en |
dc.subject | stress regime | en |
dc.title | The present-day stress field in Egypt | en |
dc.type | article | en |
dc.type.QualityControl | Peer-reviewed | en |
dc.subject.INGV | 04. Solid Earth::04.06. Seismology::04.06.02. Earthquake interactions and probability | en |
dc.subject.INGV | 05. General::05.02. Data dissemination::05.02.02. Seismological data | en |
dc.description.journalType | JCR Journal | en |
dc.description.fulltext | open | en |
dc.contributor.author | Badawy, A. | en |
dc.contributor.department | National Research Institute of Astronomy and Geophysics, Helwan, Cairo, Egypt | en |
item.openairetype | article | - |
item.cerifentitytype | Publications | - |
item.languageiso639-1 | en | - |
item.grantfulltext | open | - |
item.openairecristype | http://purl.org/coar/resource_type/c_18cf | - |
item.fulltext | With Fulltext | - |
crisitem.author.dept | National Research Institute of Astronomy and Geophysics, Helwan, Cairo, Egypt | - |
crisitem.classification.parent | 04. Solid Earth | - |
crisitem.classification.parent | 05. General | - |
Appears in Collections: | Annals of Geophysics |
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