Follow, live, the eruption of the La Palma volcano

The lava from one of the streams has reached the urban area of ​​the La Laguna neighborhood, in Los Llanos de Aridane. This laundry threatens a gas station whose fuel tanks had already been emptied weeks ago, and more recently water, and is heading towards a banana packaging company.

Another wash further north leads the La Laguna school and to continue its current trajectory I could reach the church square The nerve center of the neighborhood, which was completely evicted last week.

The technical director of the Canary Islands Volcanic Emergency Plan (Pevolca), Miguel Ángel Morcuende, He already warned that in a matter of hours it would be known which direction these washings take, and depending on this there will be “greater or lesser damage.”

The other wash that worries the most at the moment is the one that goes towards the sea, in which case it would force the entire municipality of Tazacorte to be confined. It has not yet reached the coast, sources from the Canary Islands Government confirmed to Efe. The most recent eruptive mouth, the one that opened last Friday about 300 meters south of the main cone of the La Palma volcano, has started to emit pyroclasts, reported this Wednesday the National Geographic Institute (IGN). Until now that mouth had been emitting ashes, but as can be seen in a video that the IGN has posted on social networks, it emits pyroclasts.

Itahiza Domínguez, IGN seismologist, points out on her Twitter account that for now there is no record of flows that originate from this new eruptive mouth.

Return to confinement

The residents of San Borondón, La Condesa, Marina Alta, Marina Baja and the nucleus of Tazacorte will be confined again as soon as the laundry of the La Palma volcano, which runs south of the Montaña de La Laguna, reaches the coast from which it is currently separated by just a hundred meters.

The latest report from the Department of Homeland Security (DSN) announces that the confinements will take place once that laundry reaches the sea “in anticipation of the emission of gases produced by the contact of the lava” with the water.

Since the Cumbre Vieja volcano erupted a month ago, the residents of San Borondón, La Condesa, Marina Alta, Marina Baja and Tazacorte have been confined on several occasions until air conditions have allowed this measure to be lifted.

Regarding the air quality of the last hours, the thermal inversion layer will continue at low levels until next Friday 22, This will prevent the dispersion of gases and particles in suspension, with greater intensity in the municipality of El Paso, according to data from the DSN.

In this situation, the authorities maintain the recommendation of the self-confinement of the neighbors and the use of FFP2 masks or higher in case of having to go outside.

Last night La Palma registered an earthquake of magnitude 4.8, the largest since the volcanic crisis in which the island is plunged weeks ago began, according to sources from the National Geographic Institute.

The earthquake took place at 10:48 p.m. (Canary time), with an epicenter in La Villa de Mazo and a focus at a depth of 39 kilometers, with an intensity of V (about XII), the maximum to date, and it has not been felt only on the whole island, but also in several towns in the north of Tenerife.

In the last week, 581 earthquakes have been recorded, with a maximum magnitude of 4.8 and an average depth of 15 kilometers. Since the beginning of the volcanic eruption, the total area affected has now reached 779.89 hectares, and the maximum width between the extreme points of the streams has remained at around 2,900 meters, although with undamaged areas.

Anomalies at sea

Chemical anomalies detected in the vicinity of the delta that has formed the volcano’s lava they are not “at all comparable” with the effects that were observed ten years ago with the birth of the underwater volcano of El Hierro, said the professor of Chemical Oceanography at the University of Las Palmas de Gran Canaria, Magdalena Santana.

It is “logical and normal” that these anomalies occur close to the strip of interaction between lava flow and sea waterBut they do not go “further”, said Santana, a member of the Quima group, specialized in acidification of the marine environment.

He explained that, in the case of El Hierro, the eruptive mouth was under water, where it started at about 350 meters deep, and the volcano grew to 88 meters below sea level, so that the gases that are now released into the atmosphere ten years ago left in the water.

A large part of these gases were solubilized, including sulfur, and that is why in El Hierro hydrogen sulfide was formed, which gave rise to a corrosive and “very acidic” environment, due to CO2 emissions, lowering the pH by three units.

In the case of La Palma volcano, the lava, as it flows to the sea, is practically degassed and what is seen in the area of ​​contact with the sea is the evaporation of the water resulting from the thermal shock, and what is generated is hydrochloric acid, but as a consequence of sodium chloride in seawater, he added.

PH decrease

The Quima group, of which this professor of Chemical Oceanography at the University of Las Palmas de Gran Canaria is part, took samples of the seawater before the lava flow arrived, and once the delta arrived and was formed it has returned to take samples at 15, 50 and 500 meters apart, the latter distance in which “practically” no anomalies have been detected.

Magdalena Santana has stated that, at the time, saw a slight decrease in pH, located mainly in the closest strip, and in depth, in the water column, between the first 2 and 5 meters.

They have also analyzed parameters such as inorganic carbon and alkalinity., which with the pH give information about ocean acidification, and have found a slight decrease in alkalinity in the closest samples.

Something the latter that is due to thermal shock that occurs when lava comes into contact, which is more than 800 degrees Celsius, and sea water, which is about 25.

Magdalena Santana has commented that this shock produces, in addition to the evaporation of water, a transfer of chemical equilibria, among them that of bicarbonate and carbonate producing CO2, carbon dioxide, which is released into the atmosphere, and that explains the decrease in alkalinity.

Regarding the pH anomaly, he has pointed out that it is mainly due to changes in the temperature of the water, of about 2 to 2.5 degrees in the small strip.


Source link