Deception is a young, active and also dangerous volcano: it is currently one of the most active volcanoes in Antarctica located on the island of the same name, the whole of it being a huge volcanic caldera, and registering more than 20 eruptions in the last 200 years. . The last one in 1970 (IEV 3) when between August 12 or 13, 1970 a great phreatomagmatic explosion devastated the island, this being the most violent recent volcanic activity recorded on the island. The tephra then spread over the northern half of the island, 5 marine craters, and 7 terrestrial vents. At the same time, the Antarctic base of O'Higgins (Argentina), and located 170 km from Deception Island, registered a significant earthquake on August 12 and an ash fall in later moments. The 1970 eruptions occurred in the same general area as the past marine and terrestrial eruptions of 1967. In 1972 a possible eruption was recorded again. In 1987 satellite images showed a plume coming from Deception Island on July 23, 1987, but no consistent evidence of it was found.
However, we cannot forget the most important eruption on Deception Island, in terms of material damage, occurred in 1967 (in geological time it is as if it had occurred a minute ago). Several earthquakes were detected on the island in April 1967. On December 4, 1967, the news was broadcast by telegraph cable in Argentina: "On the bay and the beaches of Deception Island, a rain of stones unexpectedly fell." On December 5, 1967, the stony precipitation had ceased, giving way to an enormous column of gases and vapours, which projected up to more than 1,600 meters, forming the typical eruptive fungus. The violent volcanic explosion that occurred (IEV 3) then destroyed the Chilean base Pedro Aguirre Cerda, the Cabo Gutiérrez Vargas Shelter, in addition to the British base B. Although the latter was again occupied from December 4, 1968, and again evacuated on February 21, 1969 in the Chilean ship Piloto Pardo (the same one that evacuated it in 1967) due to later volcanic eruptions damaging the buildings, being finally abandoned on February 23. Argentina's Decepción Base was not damaged then, but ceased to be a permanent base in 1967, becoming a summer-only base.
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Volcanic explosion (IEV 3) that occurred in 1967, then destroyed the Chilean base Pedro Aguirre Cerda, the Cabo Gutiérrez Vargas Shelter, in addition to the British base B |
Therefore, we are talking about a science-fiction island, which is the caldera of an active volcano, very active and explosive, now dormant (it is not known for how long). Being one of the few volcanoes in Antarctica where eruptions have been observed today, and the main active volcano in the Bransfield Strait basin, which is related to the Bransfield rift: a scar on the earth's crust of about 800 km in length, parallel to the South Shetland Islands and the Antarctic Peninsula, and where today ice and fire, penguins and for some years, specifically since 1989, have been a surprise: some Spanish soldiers and scientists at the base Gabriel de Castilla (in the same caldera of the volcano). Then, the latest data and analysis of lacustrine sediments from the Byers Peninsula 2019 (uab.cat) have made it possible to resolve the date of the largest eruption in recent millennia in Antarctica: 3,980 years ago, and which gave rise to the formation of the caldera of the current volcano of Deception Island, being the origin of the particular horseshoe shape characteristic of the Island. In fact, the volume of ejected rock was so large that it is comparable to that of the great eruption of the Tambora volcano in 1815, which gives us leave very calm. In addition, let us remember that just a couple of weeks ago, Argentina experienced a tsunami alert that caused the evacuation of the entire coastline, due to the eruption of an underwater volcano in Tonga, which is very similar to that of Deception Island, while that Decepción is located just a thousand kilometers from Argentina, and that it could be capable of causing a similar disaster, not to mention those who may be on the same island, or on adjacent ones, such as Livingston Island where the Juan Carlos I Spanish Antarctic Base, just 10 km from Decepción.
In relation to these latest data from the Decepción caldera. "This discovery is an example of serendipity (that is, a chance discovery) points out Dr. Sergi Pla Rabès, co-author of the article, professor at the UAB and researcher at CREAF, given that the initial objective of the study was purely climatic, and they were looking for reconstruct the climate fluctuations of the region over the last 11,700 years from the analysis of lacustrine sediments located about 40 kilometers north of Deception Island."But the presence of a layer of almost one meter of highly differentiated sediment behind level of volcanic ash, surprised everyone. Subsequent geochemical and biological analyzes indicated that these sediments were of terrestrial origin, both due to their biogeochemistry and the presence of diatoms from terrestrial environments. C14 dating also indicated that this material had sedimented suddenly and synchronously in all the ponds.All these results seemed to indicate the occurrence of a great earthquake that affected all the lakes in the area older than 4,000 years, and they pointed out that, perhaps, we were not dealing with a common earthquake, but that it could be what generated the collapse of the caldera of the volcano on Deception Island," he explains. Dr. Pla-Rabès". From what follows from these words, we speak of a "Tremendous" eruption.
So, is permanent presence on the island justified? and Is there real danger for the Spanish bases, and the tourists who visit the island?
We read: "for researchers, the probability of new eruptions on the Antarctic island is high." However, they justify their presence in it (the world 2011). In addition, «In Spain we have volcanic islands, such as Hierro, which not long ago registered an eruption in the sea. The knowledge and technology that we use here, in Decepción, later serve us to control our volcanoes, as well as Mount Teide”, adds Carlos González, an expert in geodesy at the University of Cadiz (La Voz de Galicia, February 2020). And I say, if all these tests to control volcanoes like Teide or El Hierro, etc., are worth it. Why didn't it serve to alert the volcano of La Palma? I answer myself... because it is impossible today to predict a volcanic eruption. "They (meteorologists) can study the parameters in all the space that interests them, in the entire atmosphere, with weather balloons and satellites; while we (volcanologists) can only measure in the thin layer of the earth's surface, what happens underneath we have to infer it, so our uncertainty is much greater, everything is interpretive," explains Alicia Felpeto, an expert from the National Geographic Institute - IGN, (El Confidencial 2021) to Teknautas. In 2020, Phivolcs (Philippines) stepped up the alert from level 1 to 4 on a scale of 5 (just 15 hours, no time or response at all) after activity in the phreatic crater intensified ( always at last shot) and an eruption of smoke up to 10 kilometers high will be generated. In Indonesia (Java), a country where volcanoes are perhaps the most closely monitored in the world, the Semeru volcano erupted, unexpectedly for everyone, when it was at a low level of alert: alert 2, out of 5, catching us off guard and therefore surprise to the entire population of the neighboring towns, causing hundreds of victims. And so on and on all over the world, Wakahari, La Palma, Rincón de la Vieja, etc. The scientists themselves are also victims in some eruptions: Colombia (Nevado del Ruiz), United States (Santa Elena), Japan (Unzen) etc...
As I have already mentioned, For twenty years, this island receives more than 20,000 tourists every year. It is managed by Argentina, Chile, Norway, Spain, the United States and the United Kingdom, being one of special tourist interest, but also scientific, because in this place, and as we already know, is one of the most active volcanoes in Antarctica. and its surveillance, therefore, is essential to ensure the work of scientists on the island, and of course tourists, something that is in charge of two Spanish Ministries: Science and Technology, and Transport, Mobility and Urban Agenda ( Mitma). José Luis Ábalos and Pedro Duque, signed in 2020 a protocol that ensured the volcanic surveillance of Deception Island, where the Spanish Antarctic Base (BAE), Gabriel de Castilla, is located, a stable post, in which every summer, in addition, Spanish researchers carry out dozens of scientific projects.
The new responsibilities that Mitma has therefore assumed are a natural extension of the powers of the National Geographic Institute (IGN), which since 2004 has been monitoring and assessing possible volcanic emergency situations in Spain, especially in the Canary Islands, where it has a alert and surveillance deployed in more than 150 stations with seismographs, gravimeters, GPS stations and instrumentation of geochemical techniques. Therefore, with the signing of this protocol in 2019, Mitma, in addition to initiating new activities as a member of the Spanish Polar Committee (CPE), will establish a volcanic surveillance system applying the methods and systems that it already uses for volcanic surveillance in the Canary Islands. , assisting the CPE in the decisions that correspond to it and, particularly, when "it has to notify the opening or closing of the island during the face-to-face scientific campaigns". The minister then said Ábalos. However, I believe, and always in my humble opinion, that it has nothing to do with monitoring and controlling a volcano with sensors and at a distance in the surroundings of an island such as Tenerife, La Palma or El Hierro, mediating a safety distance, to do it from the same crater of the volcano, well let's remember: Deception is in itself the huge crater of an active volcano (an active caldera), being the bases on the edge of this crater, and therefore, being exposed to an eruption: bombs ash, gases etc.. if it were of relative strength/power, which is not improbable, or rather, it is very likely —without an accurate date of course— based on the scientific discoveries in the area.
So the question is there: is it safe for scientific and military tourists to stay on the island? "Join the conversation" and comment Here:
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