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La Palma volcano lava reaches the sea

The lava from the La Palma volcano reached the sea on the coast of the municipality of Tazacorte around eleven o’clock on Tuesday night (Canary time, one more time in mainland Spain), around the area known as Playa de los Guirres (also called Playa Nueva), where it has fallen from a cliff of about 100 meters high. The contact of the lava with the sea has created smoke emanation, which travels to the interior of the island or goes out to the sea depending on how the wind blows. During the night, he moved to the mainland. The marine geosciences group of the Spanish Institute of Oceanography, which is following the progress of the magma live, has detailed that “an impressive deposit of more than 50 meters high ”in less than 45 minutes, which also continues to grow. It is a kind of pyramid that grows in the sea.

Shortly before ten o’clock on Tuesday night, the Volcanological Institute of the Canary Islands had reported that the laundry had already crossed the one known as the highway of the coast, located next to the Todoque Mountain, about 320 meters high, in the municipality of Tazacorte. The distance that separates the road from the coast is about one kilometer. This was the last major obstacle the lava flow faced before reaching the sea. The cutting of this road left the neighborhoods of Puerto Naos, El Remo and La Bombilla, also in Tazacorte, practically isolated, although the Cabildo had enabled alternative routes to access these populations.

the lava to the sea, a destroyer’s journey of 10 days of about 50 millions of cubic meters of magma, has been erratic and unpredictable. After a few days of deceleration, the wash was reactivated last Sunday, the day on which it increased its speed.

The mouth of the magma in the ocean is a phenomenon that has worried the authorities since the eruption started on Sunday 19 September, because its reaction with salt water causes toxic clouds. The only deceased officially recognized by the Teneguía volcano in 1971, in fact, died from the inhalation of these gases. For this reason, the Civil Protection device has been intensified, because it can generate explosions and the emission of harmful gases ”, according to the crisis committee (Pevolca). This situation made it necessary to decree urgently, at midnight, the confinement of four population centers and to set an exclusion perimeter of two nautical miles.

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The director of the National Geographic Institute (IGN) in the Canary Islands, María José Blanco, reported on Tuesday that one of the mouths of the volcano, in the part north, has slightly shifted towards Hawaiian behavior. In these types of eruptions, the process is usually calmer because the lava is more fluid, gases are released easily and explosions do not occur. Until now, the authorities explained in all their appearances that it was a “fissure eruption of a strombolian character”, that is, of the opening of a fissure in the mountain whose eruption is permanent, of flowing lava and dotted with explosive outbreaks, such as the Stromboli volcano, in the Aeolian Islands, north of Sicily.

The advance of the lava is constant, after the two-hour hiatus on Monday morning, when the emission of magma, smoke and ash stopped, although it was reactivated at 10. 30 (Canary time). These stops and returns to activity are common in this type of eruption. At noon on Monday, the lava path had been slowed by the orography of the island of La Palma. This circumstance led the scientific committee of the Special Plan for Civil Protection and Attention to Volcanic Risk Emergencies (Pevolca) to doubt whether the lava would end up reaching the sea. “We don’t know,” declared its technical director, Miguel Ángel Morcuende. “If the conditions that were given to the 20 had continued. 00 on Sunday, it would have arrived without a doubt. But the volcano has times of growth and others of decay. ”

The new volcano, in addition, could be recharging from a deeper lava reservoir, as happened with the underwater volcano of El Hierro, according to the head of volcanic alert of the National Geographic Institute, Carmen López, in statements to Efe. López explained that the deep seismicity located in the last hours in the Fuencaliente area, with earthquakes of magnitudes between 3.3 and 3.4 degrees, are indicative of a readjustment of the reservoir in the crust as the magma comes out. in the form of lava, ash and pyroclasts.

The lava picked up a lot of speed late Monday afternoon on its way to the sea. Its movement, and the resistance in various areas such as the Todoque Mountain, has widened the flow on its way to the coast.

When the lava tongue, around a thousand degrees of temperature, reaches the sea, just over 20 degrees, there is an explosion of water vapor that generates a dense black cloud. Lava, with its extreme heat, causes this plume, but also a chemical reaction, mainly involving chlorine, which can irritate the skin, eyes and respiratory tract. In total, there are four main dangers associated with lava flowing into the ocean, according to the United States Geological Survey: the sudden collapse of shoreline terrain and cliffs, the explosions triggered by this collapse, the waves of boiling water that generate in the environment and, finally, the column of toxic steam with hydrochloric acid and small particles of volcanic crystals.

The recovery of the underwater bottom

But not everything is destruction when the sea interacts with a volcano, as could be observed in the recent submarine eruption in El Hierro, in 2011. The oceanographic research vessel Ramón Margalef arrived on Saturday to study in detail the entry of lava into the water. The ship will also collect rocks and coral from the area. These organisms absorb sulfur and other gases spit out by the volcano, so Margalef also hopes to study the impact it will have on fauna the massive entrance of lava, explains Eugenio Fraile, researcher at the Spanish Institute of Oceanography. “The most affected will be the organisms that live attached to the seabed and that cannot move, which will probably die. But recovery can be quick. Three years after the eruption of the underwater volcano of El Hierro, these organisms had been almost completely renewed ”, he highlights.

One of the possibilities is that the sea turns turquoise green, forming a huge spot that could be observed from space. This is what happened in Hawaii in 2018. The entrance of the molten rock displaced the most superficial layers of water so that the deeper ones rose, which have many more nutrients and favored the growth of algae that stained the water.

The ship will also map the seabed after the eruption and will be able to compare this bathymetric map with the one already made in 2018, when La Palma It has already trembled due to a swarm of earthquakes.

At the moment, there is no estimate of how long the volcano will continue to spit lava. The longest eruption of all that have been documented on La Palma is that of Tehuya, which occurred in 1586, which lasted 84 days. The shortest, however, was the one that until this Sunday was the last on the island, that of Teneguía, in 1971, which lasted 24 days.

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