1909 Benavente earthquake
  | |
| UTC time | 1909-04-23 17:39:36 |
|---|---|
| ISC event | 610326344 |
| USGS-ANSS | ComCat |
| Local date | 23 April 1909 |
| Local time | 02:40:32 |
| Magnitude | Mw 6.0 |
| Depth | 10 km |
| Epicenter | 38°54′N 8°48′W / 38.9°N 8.8°W |
| Areas affected | Portugal |
| Max. intensity | MMI X (Extreme) [1] |
| Casualties | 60 dead, 75 injured |
The 1909 Benavente earthquake occurred on 23 April at 17:39:36 local in the
Geology
The northeast-trending Lower Tagus Valley of mainland Portugal covers a 3,200 km2 (1,200 sq mi) area and extends to Lisbon at its southern end. Earthquakes around the valley are usually moderate or small in magnitude with the 1909 shock being the most recent large earthquake. In the last 30 years of the 20th centory, at least 39 earthquakes had been felt; 3 with magnitudes of at least 4.0 while 16 events were between 3.0 and 3.9. The first documented earthquake in the region was
Earthquake
Reassessment of the earthquake magnitude suggest a magnitude of 6.0 on the
There are no documented surface ruptures associated with the earthquake. It is thought that the earthquake rupture along the seismogenic structure near the surface were distributed along branch faults or dips at very shallow angles.[6] If surface ruptures were to occur, it is likely they were destroyed due to flooding in the valley. Surface fissures and sand volcanoes were observed in the ground.[6]
Impact
The earthquake produced extreme shaking, peaking at X (Extreme) near the epicenter, over an area of 450 km2. Liquefaction occurred in the Tagus and Sorraia river plains. At Lisbon, 30 km away, the quake was felt VI (Strong).[7] Intensity VI was also felt in the cities of Setúbal and Évora, causing some damage. Moderate shaking (V) was felt in Spain.[8]
Despite being known as the Benavente earthquake, named after the town, it was in the towns of Samora Correia and Muge were the heaviest damage occurred. Nearly 90% of the towns were destroyed.[9] In Benavente, the foundation of a building detached from its structure and tumbled into the Tagus river. Two churches were severely damaged and unsafe for use. A seminary sustained damage when plasters fell from the front facade.[10]
See also
References
- doi:10.7289/V5TD9V7K
- ^ S2CID 129731577.)
{{cite journal}}: CS1 maint: multiple names: authors list (link - .
- ^ Jorge Talixa (12 April 2009). "Centenário do sismo de 1909 que arrasou Benavente e Samora Correia será assinalado com novo simulacro" [Centenary of the 1909 earthquake that devastated Benavente and Samora Correia will be marked with a new simulacrum] (in Portuguese). Público. Retrieved 28 October 2021.
- ^ S2CID 130288266.
- ^ S2CID 129232872. Retrieved 29 October 2021.
- ^ "Sismo sentido em Lisboa na mesma zona dos grandes abalos de 1531 e 1909" [Earthquake felt in Lisbon in the same area as the great earthquakes of 1531 and 1909] (in Portuguese). Diário de Notícias. 18 March 2021. Retrieved 29 October 2021.
- ^ "110 ANOS DO SISMO DE BENAVENTE" [110 YEARS OF THE BENAVENTE EARTHQUAKE]. IPMA. 24 April 2019. Retrieved 29 October 2021.
- ^ Nuno Miguel Ropio (22 April 2009). "Magnitude de terramoto corrigida 100 anos depois" [Earthquake magnitude corrected 100 years later] (in Portuguese). Jornal de Notícias. Retrieved 29 October 2021.
- ^ Teresa Lopes Moreira (19 March 2019). "Memórias da Cidade: Quando a Terra tremeu em 1909 e 1969" [Memories of the City: When the Earth shook in 1909 and 1969]. Correio do Ribatejo. Retrieved 29 October 2021.
Further reading
- de Pro-Díaz, Y.; Vilanova, S.; Canora, C. (2022). "Ranking Earthquake Sources Using Spatial Residuals of Seismic Scenarios: Methodology Application to the 1909 Benavente Earthquake". Bulletin of the Seismological Society of America. 113 (2): 710–731. S2CID 254778078.