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Cumbre vieja volcano canary islands: Cumbre Vieja volcano, La Palma

Опубликовано: March 2, 2023 в 5:31 am

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Категории: Miscellaneous

Stability analysis of Western flank of Cumbre Vieja volcano (La Palma) using numerical modelling

Abstract

La Palma volcanic island is one of the youngest of the Canary archipelago, being a composite volcano formed by three overlapping volcanic centers. There are clear onshore and offshore evidences of past giant landslides that have occurred during its evolution. Currently, the active Cumbre Vieja volcano is in an early development state (Carracedo et al., 2001). The study of flank instability processes aim to assess, among other hazards, catastrophic collapse and potential tsunami generation. Early studies of the potential instability of Cumbre Vieja volcano western flank have focused on the use of sparse geodetic networks (Moss et al. 1999), surface geological mapping techniques (Day et al. 1999) and offshore bathymetry (Urgeles et al. 1999). Recently, a dense GNSS network and satellite radar interferometry results indicate ground motion consistent with deep-seated creeping processes (Prieto et al. 2009, Gonzalez et al. 2010). In this work, we present a geomechanical advanced numerical model that captures the ongoing deformation processes at Cumbre Vieja. We choose the Finite Elements Method (FEM) which is based in continuum mechanics and is the most used for geotechnical applications. FEM has the ability of using arbitrary geometry, heterogeneities, irregular boundaries and different constitutive models representative of the geotechnical units involved. Our main contribution is the introduction of an inverse approach to constrain the geomechanical parameters using satellite radar interferometry displacements. This is the first application of such approach on a large volcano flank study. We suggest that the use of surface displacements and inverse methods to rigorously constrain the geomechanical model parameter space is a powerful tool to understand volcano flank instability. A particular important result of the studied case is the estimation of displaced rock volume, which is a parameter of critical importance for simulations of Cumbre Vieja tsunamigenic hazard assessment. Carracedo, J.C, Badiola, E.R., Guillou, H., de La Nuez J., Pérez Torrado F.J., (2001) Geology and volcanology of La Palma and El Hierro, Western Canaries, Estud. Geol. 57 175- 273. Day S.J., J.C. Carracedo, H. Guillou, P. Gravestock, Recent structural evolution of the Cumbre Vieja volcano, La Palma, Canary Islands: volcanic rift zone reconfiguration as a precursor to volcano flank instability? J. Volcanol. Geotherm. Res. 94 (1999) 135- 167. González, P. J., Tiampo, K. F., Camacho, A. G., & Fernández, J. (2010). Shallow flank deformation at Cumbre Vieja volcano (Canary Islands): Implications on the stability of steep-sided volcano flanks at oceanic islands. Earth and Planetary Science Letters, 297(3), 545-557. Moss, J.L., McGuire, W.J., Page, D. (1999). Gruound deformation monitoring of a potential landslide al La Palma, Canary Islands. Prieto, J.F., Gonzalez, P.J.,Seco, A., Rodriguez-Velasco, G., Tunini,L., Perlock, P.A., Arjona, A., Aparicio, A., Camacho, A.G., Rundle, J.B., Tiampo, K. F., Pallero, J.L.G., Pospiech, S., Fernandez, J., 2009. Geodetic and structural research in La Palma Island, Canary Islands, Spain: 1992 – 2007 results. Pure Appl. Geophys. 66, 1461 – 1484. doi:10.1007/s00024-009-0505-2 Urgeles R., D.G. Masson, M. Canals, A.B. Watts, T. Le Bas, Recurrent large-scale landsliding on the west flank of La Palma, Canary Islands, J. Geophys. Res. 104 (B11) (1999) 25331-25348.

Inside La Palma’s volcano, gas emissions mark colourful terrain

LA PALMA, Spain, Jan 24 (Reuters) – Two bare pine tree trunks remain standing inside the jagged and colourful main crater of the volcano on the Spanish island of La Palma, while gas emissions and high temperatures continue though they are easing a month after the eruption ended.

A Reuters crew was on Friday granted rare access to the edge of the volcano’s craters with a team from the Canary Islands Volcanology Institute (Involcan), who went inside one of the six craters to measure gas emissions and temperatures and check that their monitoring stations were functioning well.

Powerful gas emissions during the 85-day volcanic eruption have tainted parts of the crater yellow, orange and white.

The surrounding terrain is pitch black, with violent tongues of lava scattered along slopes completely covered with a thick blanket of volcanic ash. Scores of burnt pine trees are now beige.

“Despite having been inside (the crater) many times, it always strikes me how big it is. Once you are inside you realise it’s huge, gigantic,” said Pedro Hernandez, the Involcan volcanologist leading the team.

“There are many craters and gas emissions continue to be very impressive from a visual perspective.”

The volcanic eruption in La Palma in the Canary Islands, which officially ended on Christmas Day, was the most devastating in Europe in 80 years, he said.

[1/6] Members of the INVOLCAN technical team take measurements next to the crater of the Cumbre Vieja volcano, in Cabeza de Vaca, on the Canary Island of La Palma, Spain, January 21, 2022. Picture taken January 21, 2022. Picture taken with a drone. REUTERS/Borja Suarez

Rivers of lava destroyed around 3,000 buildings and scores of fields covering 1,219 hectares, although no direct deaths were reported.

Temperatures inside the craters were around 840 degrees Celsius, lower than the 1,100 degrees registered around two weeks before. But extremely high temperatures could continue for several years, said Hernandez, 53. This is the eighth volcanic eruption he has studied on the ground.

His team also checked in person that gas emissions from the craters’ edges had slightly decreased but the volcano continued to emit sulphur and carbon dioxide, which could be smelled in the surrounding area.

Fifteen minutes from the crater by foot, where the Involcan expedition left its vehicles, the ground remained warm.

What is most striking for locals is that what used to be a low set of green slopes overlooking the Atlantic Ocean and the towns below has now been transformed forever after the eruption brought a huge volcanic cone to the surface.

The area close to the craters remains closed to the public in a closely policed perimeter, leaving most of the area in almost absolute silence only interrupted by birdsong and the wind.

(This story has been refiled to correct formatting)

Reporting by Joan Faus, Borja Suarez and Horaci Garcia; Editing by Jessica Jones and Emelia Sithole-Matarise

Our Standards: The Thomson Reuters Trust Principles.

The volcanic eruption in the Canary Islands was caught on video, what happened, are there any victims

On September 19, 2021, the news of the volcanic eruption in the Canary Islands appeared. Photos and video frames from the place where this emergency happened have already been published on the Web, and have become available to every user.

  • Details of the volcanic eruption in the Canary Islands
  • Video of the volcanic eruption of Cumbre Vieja

Details of the volcanic eruption in the Canary Islands

Foreign news agencies report that a volcano called Cumbre Vieja erupted on the Spanish island of Palma, which is part of the Canary Islands archipelago. Note that the lava flows moved towards small settlements, which are located nearby. The authorities started evacuating local residents from four settlements.

The eruption occurred against the background of increased seismic activity. Not so long ago, Spanish seismological centers reported that the situation had noticeably worsened, and they called on the centers to prepare for tremors. The island authorities said that local residents of the settlements surrounding the volcano should leave their homes. The situation is so critical that even cattle have to be evacuated. Note that in the settlements that are located near the volcano, more than a thousand people live. nine0003

The Spanish Minister of Defense stated that military personnel are helping with the evacuation. The National Geographic Institute of the country reports that scientists over the past seven days have recorded more than 22 thousand tremors, the maximum magnitude of which is 3.8 points. These tremors were recorded in the Cumbre Vieja Natural Park, where the volcano of the same name is located.

It is known that Palma, where the eruption occurred, is an island of volcanic origin. Several volcanoes run along the central part of the island. The last time a large-scale volcanic eruption on the island occurred in the early seventies, then, unexpectedly for the locals, a volcano called Tenegia became more active. nine0003

Video of the Cumbre Vieja volcano eruption

What happened on the island of Palma was captured on video and photos. In some frames, which were provided by Reuters journalists, you can see how the lava jet splashed into the sky as if it was blood that adorned the snow-white clouds. What is happening is terrifying, the volcano itself is not very large, but it stands out noticeably against the background of green trees, which seem to be destroyed in the near future.