The Canary archipelago consists of 7 islands, but when the Portuguese discovered the islands, stories were being told about an eighth island, that was sometimes seen to the West of La Palma, El Hierro and La Gomera. When sailors tried to reach it, the island was covered in mist and disappeared. Stories about ghost islands like this one seem imaginative tales at first, but there may be some form of truth in it. In 1867 an island suddenly rose from the sea near Terceira in the Azores, but only a few days later it was swallowed again by the sea. Maybe the eighth island was not just a story either, because events like this are indeed possible in this region, as the Canaries lay in a highly active volcanic zone.
The seven islands and six islets of the Canaries are in fact the emerged tips of a volcanic mountain range, situated just West of the African Continental Margin and hidden by the Atlantic Ocean. This means that under the surface of the deep blue ocean they are connected. It is a fact that the waters surrounding the islands are very deep, but to say they all rise directly from the ocean floor is just not a correct statement. It would only be true for part of the archipelago, more specifically the western part with Tenerife, La Palma, El Hierro and La Gomera. These islands are indeed volcanic peaks going all the way down to the deep Atlantic floor. Lanzarote, Fuertaventura and the six islets though are flatter islands, yet also volcanic, but emerging from a submarine plateau, known as the Canary Ridge. This
ridge rises approximately 4,600 feet from the bottom of the ocean. Because of the extreme volcanism in this region (the whole archipelago was formed after volcanic eruptions and it is said that the volcanism in the area is the result of a mantle hotspot under the islands), it is possible that once a landmass in this area was above the surface, and did
not just sink because of the rising of the sea level, but more because of seismic activity such as earthquakes and tsunamis combined with or caused by volcanic eruptions at the end of the last Ice Age.
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