A tsunami, at the origin of the Maspalomas dunes


One of the two hypotheses about the origin of the dunes of Maspalomas sits on a tsunami that washed away the coasts of the Canary Islands 266 years ago, the Lisbon earthquake tsunami. They are just met on November 1. On that date, All Saints’ Day, 1755, the devastating Lisbon earthquake, 8.5 magnitude and that it killed about 100,000 people. The great waves that it generated reached the coasts of the American continent and along the way swept the coastline of the Atlantic islands, including the Canary Islands. In Gran Canaria, they dragged sand and deposited it in the area of ​​the tip of Maspalomas.

This hypothesis of the Lisbon tsunami as the origin of the Mapalomas dunes, defended by researchers from the University of Las Palmas de Gran Canaria (ULPGC), clashes with the other older theory, which proposes the slow formation of the dune system, something that would begin to form about 10,000 years ago.

In these days of controversy over mentions of the possibility of a tsunami associated with the eruption in the Cumbre Vieja massif, on La Palma, we review the consequences of Lisbon tsunami, the largest of the historical tsunamis suffered in the Canary Islands of which there is documentary evidence. The arrival of the Lisbon earthquake tsunami to the Canary Archipelago attests to the then Captain General of the Canary Islands, Juan de Urbina, in a letter addressed to the Minister of State, Ricardo Wall. In it, he details the damage caused by the tsunami on the coast of Gran Canaria, especially in Las Palmas de Gran Canaria and its port. It also tells you that it was noticed on the islands of Fuerteventura and Lanzarote.

Letter from Juan de Urbina to Minister Ricardo Wall

Dear Sir, having reached these Islands the news of the damage caused by the earthquake that was felt in that Court and elsewhere, on the morning of the first of November it seemed to me necessary to notify Your Excellency of our happiness in this tragedy for the King to share.

On that day, around eleven o’clock in the morning, the sea being calm, the dock steps were raised, but this avenue was not so great that it became noticeable to all, nor did it cause any other effect on this port and its coasts than to admire the few who noticed this novelty.

In this same Island (Tenerife), along the coast called the Northern Bands, the elevation of the waters was higher and it was noticeably noticed with some shock from all the inhabitants of this place, but without damage.

The same movement of the sea was experienced on the island of Gran Canaria and the inhabitants of their main city were watching from the balconies and near the marina this sudden swelling of the waters at the same time and with the greatest astonishment, and much more when they saw that, withdrawn for eight or ten minutes, they returned with greater impulse on the untouched limits in the previous invasion, repeating up to three times on that island this great novelty, but without damage or other circumstance worth noting, and only in the main port of that island, named the Puerto de la Luz, distant one short league from the city, the sea entered and flooded the hermitage of Our Lady of Light there, and having withdrawn like a pistol shot within its old limit, he discovered the hull of a ship, of whose wreck there is no memory, and left the hermitage full of fish.

The same movement was experienced on the islands of Fuerteventura and Lanzarote, but also without havoc; only in the last one, some salt flats from which those natives were supplied were ruined.

Having learned from letters from Spain, and others from different parts of Europe, how almost universal was the earthquake of that day and the catastrophe that many peoples suffered and, what is sadder, countless people, we have given to God repeated thanks with the greatest solemnity, to which I gave the beginning of the day of the Apostle Saint Matthias, and this people and all those of this Island continued with the greatest devotion, because having filled Europe this day with astonishment, horror and tragedy, we, by the mercy of God, only had something to admire, but not under circumstances that aroused fear.

It is all that has happened worthy of participating in VE In these Islands and their seas.

God save you Santa Cruz of Tenerife, March 6, 1756

To the exmo. Mr. D. Ricardo Wal.

In Urbina’s letter to the minister there is no reference to what happened on the southern coast of Gran Canaria. However, the scientific evidence found in studies carried out in recent decades on the dunes for their conservation and other documentary references feed the theory of their origin from the tsunami generated by the Lisbon earthquake.

The great change in the conception of the dune genesis occurs with the survey that was carried out in Playa del Inglés in 2008 on the occasion of the Comprehensive Study of the Beach and Dunes of Maspalomas. This borehole drilled to a depth of 19.5 meters and yielded the first results, which once studied, suggested that the dunes did not form as long ago as previously thought. Specifically, around the eighth and ninth excavated meter, the analyzed sedimentological elements showed an abrupt break in the time line that could only be explained if the dune field had been formed between 1720 and 1870.

From there, the researchers looked for historical references to the Maspalomas dunes and concluded that they did not exist before 1800. There are no references to them in historical, cartographic or naturalist documents that visited Gran Canaria between the 17th and 18th centuries.

In a report prepared by journalist Borja Valcarce for THE PROVINCE in February 2008, the hypothesis of the tsunami as a generator of the Maspalomas dunes is offered in detail and states that the ULPGC is delving into the investigation. The text also highlights that in the geographical descriptions and cartographies of Antonio Riviere (1742), the existence of the dunes is not mentioned at any time; or those of the engineer Miguel Hermosilla (1785), in which he talks about the Charco de Maspalomas but does not write a word about the greatest tourist attraction in Gran Canaria. It is from 1838, when in the atlas drawn by PB Webb and S. Berthelot, a wide sandy beach is glimpsed, which coincides with the current northern sector of Playa del Inglés.

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