Direct | Magma release intensifies after a lateral rupture

Under the laundry volcano of the Cumbre Vieja de La Palma at least two volcanic tubes have formed that retain heat and they make it easier for the lava to flow more fluidly and at a higher speed. These galleries, which are common in the Canary Islands, are created when the magmatic material that emanates from the interior of the earth is very liquid and passes through areas where the topography is not very rugged. The presence of these volcanic tubes helps to channel the wash, but in turn they make the lava maintain a high temperature, so it advances faster and reaches lower heights. The Volcanological Institute of the Canary Islands (Involcan) has shared this finding in the meeting of the teams of the Volcanic Emergency Plan of the Canary Islands (Pevolca), after the researcher Sonia Calvari, from the Istituto Nazionale di Geofisica e Vulcanologia of Italy, carried out a simulation of the evolution of the streams, through satellite images, with which he concluded that the languages ​​disappeared in certain points and reappeared in areas closer to the coast.

To the collapse the west wall of the volcanic cone, on Sunday there was a spillage of the stored contents, as if a dam was breaking. This generated ugreat expansion of the lava and dragged large blocks of the volcanic edifice down the hillside. Scientists monitor and monitor the progress of the streams, which, as they are more fluid, could lead to some change of course and new civil protection measures could be required to safeguard the safety of people who could be affected by the change of route of lava.

Both the changes in the physiognomy of the cone, with construction and collapse stages, as well as the explosiveness peaks are natural within a strombolian eruptive process such as La Palma, which alternates explosive phases, of low or moderate intensity, and effusive phases, in which the lava flow intensifies. The director of the National Geographic Institute in the Canary Islands, María José Blanco, explained that they have calibrated the magnitude of the explosiveness of the eruption according to the Volcanic Explosivity Index (VEI), which uses a scale ranging from 0 to 8 and, in the case of the La Palma eruption, the assigned value is 2.

The lava expelled by the Cumbre Vieja volcano already occupies an area of ​​413.38 hectares. In the last 24 hours, the affected territory has increased by 14.2 hectares.

During Sunday afternoon, there was an increase in the frequency and intensity of the explosive activity, lasting several minutes, verifying the emission of ballistic bombs with a distance of up to 800 meters. This distance is within the population’s exclusion radius, which is 2.5 kilometers, but the episode has been made known to scientists and emergency personnel working in the area.

Since the volcano erupted on September 19, lava has occupied 413.38 hectares of La Palma, 14.2 in the last 24 hours. The perimeter of the area affected by the wash is 36.3 kilometers, although within that space there may be areas that have not been razed, but are isolated in the middle of the malpais. The width of the wash, in some sections, reaches 1,250 meters, 300 more than on Saturday. The technical director of the Volcanic Risk Prevention Plan (Pevolca), Miguel Angel Morcuende, explained that this is becausee lava passes through areas of the terrain that act as “holes“fills them up and when they overflow an effect of” communicating vessels “is generated.

The lava has engulfed 1,046 buildings, while another 128 may be partially affected, according to the latest data collected by the satellites of the European ground surveillance program, Copernicus, which correspond to early Sunday morning. La Palma’s road network suffers various cuts due to the advance of the magmatic material tongues, which has already destroyed 33.2 kilometers, of which 30.7 are completely destroyed. Copernicus figures in 4,819 hectares the territory covered by the ashes. The intense cloudiness that has predominated in the Aridane Valley made it impossible for the satellites to update the data during the early hours of Monday.

The delta that began to form on Tuesday on the coast of La Palma when the wash reached the sea after ten days engulfing homes and infrastructure, already measures 37.2 hectares, 8.2 more than the previous day. The term collision between lava and seawater generates a marine plume of water vapor and hydrochloric acid (HCl) that concentrates in the contact environment. The evolution of the creation of the delta is monitored by several scientific ships, regional and national, which measure the levels of carbon dioxide (CO2), HCl and sulfur dioxide (SO2) in the area.

A week ago the lava reached the coast and began to fall into the sea. The delta that has been created on La Palma coast has already reached a size of 32.7 hectares.

This Monday several active centers were observed inside the main crater, two of them located in the northwest of the side of the cone. However, the Pevolca does not rule out the appearance of new emission centers in the environment. According to the latest measurements, the volcano emitted 16,700 tons of SO2 on Sunday, a value higher than the previous day. In addition, the diffuse emission of CO2 throughout the Cumbre Vieja area yields a value of 1,718 tons per day. Low CO2 values ​​continue to be maintained in terms of air quality in all stations on the island, except for specific peaks in Los Llanos and El Paso, but of low intensity and far from the thresholds established in the regulations in force. Regarding particles less than 10 microns (PM10), lower values ​​were measured compared to indoor days, although the daily threshold was once again exceeded at the Los Llanos station, with an average of 96 micrograms per cubic meter.

The column of ash and gases reached a height of 4,500 meters. The Pevolca foresees that the wind will carry the plume of ash and gases towards the south-southwest of La Palma. Thus, the area of ​​La Palma most affected by the ash fall will be precisely the south-southwest slope. The predicted orientation of the volcanic plume is favorable for the operation of the Canarian airports. In addition, a wet maritime air mass will enter the Islands, whiche will help decrease atmospheric stability and improve air quality. The Ministry for the Ecological Transition and the Demographic Challenge offers from this Monday information in real time on the quality of the air in La Palma through the National Air Quality Index (ICA), which allows checking the parameters that mark the measurement stations of the national surveillance network.

Morcuende wanted to convey a message of tranquility about the increased seismicity in the southern area of ​​La Palma. As detailed in the press conference after the Pevolca meeting, the seismic swarm “has traveled” to the area where it was detected a week before the eruption began and clarified that the movements are taking place at deep levels of the crust, between 10 and 20 kilometers. “We are not talking about superficial seismicity that could give rise to other phenomena, nor do we have to fear, in principle, any new mouth as a consequence of this seismicity,” he said. In the last few hours there have been dozens of events of magnitude greater than 3, which increases the probability that more earthquakes felt by the population will be registered and that small landslides may occur. The most intense shock occurred in Villa de Mazo and was 3.7 degrees.

Residents evacuated from neighborhoods located more than 1.5 kilometers from the laundry and outside the security zone were able to access their homes yesterday to collect belongings and personal items. The Cabildo de La Palma made sure that the entrance was controlled, through the authorized routes and always under the supervision and accompaniment of the security forces in charge of the device. On Sunday this operation had to be suspended due to the worsening air quality, which also forced the withdrawal of scientific personnel and emergency teams that were close to the volcano.


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