Mw 6.1 Azores Cape Saint Vincent Ridge on 12/02/2007
An event of magnitude Mw 6.1 occurred on 12/02/2007 at 10:35 UTC off coast of South-Western Portugal. Distances to cities: 338 km South of Lisbon, 247 km South-West of Faro, 369 km North-West of Rabat. This event is the largest one in the region since 1969. It shows little aftershocks activities. The largest aftershock in the following 10 days within a radius of 100 km around the main shock reached magnitude 3.8. In the 10 first days following the main shock, the total number of aftershocks within a radius of 100 km around the main shock, with magnitude ranging from 2.5 and 3.8, is 7.
It occurs in the region where the 1755 earthquake presumably occurred. For more information about the 1755 earthquake, visit the page of the "250th anniversary of the Lisbon Earthquake". and the Wikipedia page.
|Main shock location
More information on the main shock
|Moment tensors solutions|
Time evolution of the seismicity in Cape St Vincent region before and after the main shock
|During the 30 days before the main shock||During the 10 days before the main shock||During the 10 days after the main shock|
The white circle represents a radius of 100 km around the main shock epicentre in which the aftershocks are studied in the first paragraph.
Instrumental seismicity from 1964 until 19/02/2007 in Cape Saint-Vincent region
Compilation of ISC catalog (1964-2001) and EMSC data (since 2002).
|Spatial distribution of the seismicity||Number of M>5 events per year since 1964 in the region defined by the map on the left hand side|
The February 12th, 2007 event is the largest one in the region since 1969. As an avarage, during the last 43 years, 1 event of magnitude greater than 5.0 occurred in the region each 3 years. Over the last 5 years, an average of one event per year of magnitude greater than 5.0 occurred in the region.
This event has been widely felt in Portugal, Southern Spain and Western Morocco and up to 700 km away of the epicenter (Salamanca, Madrid). There has been no damage associated to the event even in the closest cities : Casablanca, Rabat, Faro, Lisbon.
|Map of the area where the event was felt
(Generated from the "Report your experience" questionnaires collected by the EMSC)
- Windows, doors, crockery, hanging objects swung, small objects fell in Lisbon (338 km of the epicenter).
- Widely felt and small objects swayed in Sevilla (420 km of the epicenter) and Huelva (337 km).
- Weakly felt in Tanger (401 km of the epicenter).
- Weakly felt in Madrid (768 km of the epicenter) and mainly in the high buildings.
Analysis of how the event has been felt in different parts of a building in Madrid (by P. Murphy Corella).
Distribution of EMS-98 intensities from the 12 February 2007 Cape St Vincent earthquake, from data collected by EMSC:
(From R. Musson - 2007)
> EMSC Newsletter (April 2007)
> ORFEUS Newsletter (May 2007)
- Source Mechanism of the February 12, 2007, San Vicente Cape Earthquake Mw 5.9 (Buforn et al.)
- The ML 5.9 Magnitude Earthquake of 2007.02.12, SW San Vincent Cape (Carrilho et al.)
- The 12/02/2007 SW Cape San Vicente Earthquake: SFS (San Fernando SP) and WM (Western Mediterranean) networks preliminary reports (Martin-Davila et al.)
Links to regional seismological institutes
- Instituto de Meteorologia, Seismologia (Lisbon, Portugal)
- Instituto Geografico Nacional (Madrid, Spain)
- Centre National de la Recherche Scientifique et Technique, Geophysics Laboratory (Rabat, Morocco)
- Departement de Physique du Globe (Rabat, Morocco)