College of Engineering >
Earth and Atmospheric Sciences >
Active Tectonics, Geophysics, and Structure >
Middle East and North Africa Region Projects >
Please use this identifier to cite or link to this item:
|Title: ||An integrated geophysical investigation of recent seismicity in the Al-Hoceima region of North Morocco|
|Authors: ||Calvert, A.|
Earthquake hazard in Morocco
|Issue Date: ||1997|
|Publisher: ||Seismological Society of America (SSA)|
|Citation: ||Bulletin of the Seismological Society of America, vol. 87, no. 3, p. 637-651, 1997|
|Abstract: ||Data produced by the Moroccan national seismological network and marine seismic reflection profiles are used to investigate the most seismically active region in Morocco, located on the Mediterranean coast at the intersection of the Rif mountain belt and the submarine Alboran Ridge. This region, in the vicinity of the city of Al-Hoceima, marks an east-west transition in the marine and land deformation styles of the distributed plate boundary between Africa and Iberia, and was the site of a Mw=6.0 earthquake on May 26, 1994.
The epicenter of the Al-Hoceima earthquake is relocated onshore, refining the initial submarine location close to the Alboran Ridge. The spatial distribution of foreshocks and aftershocks shows a NE-SW trend that continues partly offshore and is subparallel to the earlier, yet still prominent, Miocene geologic structural trend. The predominantly strike-slip focal mechanism for the Al-Hoceima event is characteristic of earthquakes in the region. Marine seismic reflection profiles, that intersect the offshore region of seismicity, image active high angle faults with possible strike-slip components. The seismicity trend is not directly related to the submarine Alboran Ridge or the geomorphologically prominent Nekor fault. Deformation appears to be occurring on a number of subsidiary strike-slip faults that together compose a NE-SW zone of distributed shear.
The distributed strike-slip and documented normal faulting taking place in the eastern Rif mountains, although characteristic of the Rif region, are in contrast to the thrusting style of deformation that occurs farther to the east in the Algerian Tell Atlas. This may be related to the reported lateral variations and evolution of the convergent plate boundary in these regions during the Neogene and Quaternary times.|
|Description: ||Copyright 1997, SSA.
|Appears in Collections:||Middle East and North Africa Region Projects|
Prof. Muawia Barazangi
Items in eCommons are protected by copyright, with all rights reserved, unless otherwise indicated.