Azores, 9 islands and maybe 10 one day ?

credit picture: dive visitazores


The archipelago of the Azores is located in the Atlantic Ocean at the distance of 1815 km from the mainland Portugal.

From a geological point of view, all the Azores islands are of volcanic origin and are oceanic islands that emerged from the sea floor due to the progressive piled up of submarine volcanic products. A process that could have started about 36 million years.

The islands emerge from the sea floor at 2 000 meters deep, associated with the triple junction of the North American, Eurasian and African tectonic plates.


In the Azores Plateau area the plate boundary between Eurasia and Africa corresponds to the “Azores Block”. This block is also moving at different speeds and directions.

Under the waters of the Azores there are a lot of seamounts in different locations and different depths, but one of them is calling our human curiosity! Did you guess which one?

We call it Banco do Castro de São João, it is located between the central group and the oriental group. The last eruption was in 1720.

The maximum elevation is 12 meters deep and it is still active!! Divers can appreciate the volcanic activity and dive in the middle of bubbles!

One of the The hypothesis is that MAYBE one day it will be the 10th island of the Azores !


We still have so many things to discover and learn from our Planet ! And many phenomena are unpredictable!

Have a lovely day!



França, Z., et al. (2003). Geologia dos Açores: uma perspectiva actual. Açoreana, 10(1), 11-140.

Nunes, J. C. et al. (2003) Caracterização vulcanológica do Banco D. João de Castro (Açores): novos dados. Ciências da Terra (UNL), no esp. V, CD-ROM: D55-D58.


About Marylou

Marylou is a Marine Biologist and Master in Oceanography. She is one of our Marine Wildlife Guide and is responsible for Science Education at TERRA AZUL. Originally from France, she studied in Canada and Belgium and loves being out to sea to share her knowledge with you.

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