Autonomous seismological station (Fairfield node) of the national mobile seismological park SisMob deployed on the lake of Vallunden (Svalbard - Norway) during Icewaveguide project.

• Main Author: Vial, Benjamin
• Other Authors: Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement IRD : UR219-Université Grenoble Alpes (UGA)-Université Gustave Eiffel-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )
• Format: Still Image
• Language: English
• Published: HAL CCSD 2019
• Subjects: Fairfield node; Seismological station; Field instrumentation; Seismology; SISMOB; Station sismologique; Instrumentation mobile; Sismologie; RESIF; [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph]; Arctic; Frozen Lake; Jan Mayen; Norway; Svalbard; Sveagruva; Vallunden; Global warming; ice pack; Sea ice
• Online Access: https://medihal.archives-ouvertes.fr/hal-03030359; https://medihal.archives-ouvertes.fr/hal-03030359/image; https://medihal.archives-ouvertes.fr/hal-03030359/file/ICEWAVEGUIDE_photo_58.jpg

The sea ice is disappearing with global warming, and if the trend is clear over the last few decades, scientists are still wondering about the speed of this disappearance, which seems much greater than the models predict.To better assess the quality of the polar ice (its thickness, its degree of fracturing), a team of scientists conducted a reconnaissance and test expedition in February and March 2019. The objective was to listen to the natural vibrations of the ice pack to deduce its mechanical characteristics (thickness, solidity, etc.). A pilot site was identified in Svalbard, at 78° north latitude, as close as possible to the Arctic pack ice. 250 seismic sensors (seismometers) from the SisMob mobile instrument park of Résif were installed there for one month to record the vibrations and murmurs of this small ephemeral pack ice (it forms only a few months per year) in the Sveagruva fjord.This picture shows one of the one hundred autonomous seismological stations (Fairfield nodes) belonging to the national park of land mobile seismological instruments (Sismob) which were installed for a measurement campaign on the frozen lake of Vallunden (Svalbard - Norway).The ice was first excavated using a specific tool, designed in the laboratory and made by a subcontractor. This ice-cutting tool made it possible to quickly dig a hole the size of the nodes, thus facilitating their positioning.Sismob is one of the specific actions of the French Réseau sismologique et géodésique français Résif, a national research infrastructure dedicated to the observation and understanding of the internal Earth structure and dynamics. Résif is based on observation networks of high technological level, composed of seismological, geodetic and gravimetric instruments deployed densely throughout France. The data collected allow to study with a high spatio-temporal resolution the ground deformation, the superficial and deep structures, the seismicity at the local and global scale and the natural hazards, especially seismic, on the French ...