An international study conducted by the Institute of Geosciences (IGEO), the joint center of the Supreme Council for Scientific Research (CSIC) and the Complutense University of Madrid (UCM), managed to detect magma accumulation near the surface months before an eruption occurred volcanic. This study analyzes the deformation of the ground produced by volcanic activity. It uses a methodology that combines cutting-edge InSAR satellite radar observation with a new interpretation technique developed by IGEO researchers during the volcanic eruption on the island of La Palma in 2021. The results of the study have been published. magazine Scientific Reports.
“Structural model of the subterranean crust of the island with the combination of resources obtained by this methodology, can help predict possible opening of cracks or eruption vents during volcanic reactivation events “To predict the start time of the next eruption, along with other techniques,” explains IGEO researcher José Fernández, first author of the paper.
The eruption at La Palma began on September 19, 2021, and was accompanied by a seismic swarm that preceded and 8 days earlier, beginning on September 11, in which more than 6,600 events were detected. The results obtained in this study show that between 13-20 September, which coincides with the last days of the seismic swarm, seen Shallow welds showing horizontal and vertical fracture of the ground that will cause an eruption fissurefracture
The configuration obtained in this study of the magma supply system and associated fractures, help explain some processes Gas emissions after the explosion, such as continued gas emissions in Puerto Naos and La Bombilla areas, still hindering the return of residents a year later.
A previous paper published by the same scientific team in early 2021, eight months before the eruption on La Palma, stated that between 2009 and 2010 the island’s volcanic reactivation had begun. Moreover, Detected a significant break in the ground under Cumbre Vieja Associated with this process in 2019 and 2020.
“This fracture represented the possible path the magma took towards a zone of structural weakness.It facilitated the formation of a magmatic reservoir at a depth of two to five kilometers in the Cumbre Vieja area, about three and a half months before the eruption began. This location of the reservoir highlights the importance of knowing the structural pattern of the island, along with the routes it has taken in the rise of magma in recent eruptions,” adds Fernández.
About two months before the explosion, Data obtained by the researchers at the end of July 2021 reflected signs of vulnerability in the cortex. before a larger magma rise. “Had the new interpretation technique been used at that time, this result could have been an alarm, leading to increased surveillance of the area to monitor the last stage before the explosion in real time,” the IGEO researcher commented.
“This new study is based on not only knowing the magmatic supply system and deep fracturing, but also structure of the cortexpotential sites of magma accumulation in shallow reservoirs and possible explosion paths. This is fundamental knowledge in assessing volcanic risk and planning infrastructures and urban development, both on the island and in other volcanic areas, said José Fernández.
Reference work: DOI: 10.1038/s41598-022-23998-w
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