December 21, 1641 Tsunami: Azores, Portugal

Reference #41:

1641 December 21. Azores. About noon, three waves inundated the port of Velas (38’41’N.,23'13W.) Ilha de Sao Jorge (38'38'N., 28'03W.) and the lower part of the town. A convent and several houses were destroyed. There were about 50 victims.

Reference #1919:

Around noon, three waves' invaded the port of Velas (San Jorge) and the lower part of the village. A convent and several houses destroyed, around fifty victims.

Reference #5046:

1641 December 21. 38.4 N 28.1W. Earthquake source tsunami. The coastal flood of 21 December 1641 affected the southern shore of S. Jorge Island. Avellar's (1902) description refers only to a disturbance of the sea surface, at noon, in the form of "...three tides so strong that demolished the covent of Franciscans and drowned the nearby village up to the level of the ceilings".

Reference #11164:

1641 December 21. 38.4 N., 28.1 W. Probable tsunami, Cause earthquake. Andrade et al. (2006) (reference #5046) report that a tsunami affected the southern shore of S. Jorge Island. Avellar's (1902) description refers only to a disturbance of the sea surface, at noon, in the form of "...three tides so strong that demolished the convent of Franciscans and drowned the nearby village up to the level of the ceilings”. Inspection of the local topography suggests a run-up height slightly less than 9 m. Berninghausen (1964) describes this event based upon Agostinho (1935) in the following terms: ".about noon, three waves inundated the port of Velas ...Ilha de Sao Jorge.and the lower part of the town. A convent and several houses were destroyed. There were about 50 victims.” (Andrade et al., 2006).

Reference #13057:

Around 12 h 00 min (local time) of 21 December 1641 the sea flooded Vila das Velas, S. Jorge Island, causing destruction and leaving 50 people injured.

[...]Some authors consider that the flood should be general in all islands and assume a local tectonic source (Guedes and Oliveira 1997; Andrade et al. 2006; Borges et al. 2008; NGDC/WDS n.d.), with the epicentre located in Pico Island. However, Silva (2005) has no reference to a tectonic event near S. Jorge Island at that time. In fact, an earthquake with tsunamigenic potential, i.e. with a high magnitude, would inevitably have a severe impact on S. Jorge and the nearby islands. Likewise, a tsunami generated on a distant seismic source should first reach any of the neighbouring islands of S. Jorge owing to its geographical location.

Thereby, considering that the flood occurred in winter and the high frequency of floods related to storms recorded in Vila das Velas over the years, it is more likely that the 21 December 1641 is associated with a meteorological phenomenon. (reference #13057)