With this device you can get a wide network of seismographs «at a very low price»Although at the moment, it cannot be in real time. This is how the geophysicist of the Barcelona Institute of Marine Sciences (ICM-CSIC) and head of this scientific project, Antonio Villaseñor. The DAS interrogator is capable of providing investigators with one virtual seismograph for every 10 meters of cable.. On La Palma, where the fiber expands about 4 kilometers below the ground, represents a total of 400 different seismographs along this fiber. In Tenerife, the number would amount to 1,800 seismographs. These two interrogators in particular have been developed by the Photonic Engineering Group of the University of Alcalá de Henares (UAH) and the Optics Institute of the CSIC (IO-CSIC) and they are being tested for the first time live in the Canary Islands. On Teide, it is expected to be installed for another couple of weeks, to then evaluate its operation. On La Palma, however, they will remain installed longer. “The idea is for them to be there throughout the emergency and even to develop a method to get the data in real time,” explains Villaseñor. Thanks to the technological advances of this device, it is capable of perceiving certain characteristics of earthquakes that until now could not be known in advance, such as the direction from which the seismic waves come and where they flow.
This device is capable of knowing the exact point from which seismic waves start
This type of device has also been installed, by the Instituto Volcanológico de Canarias (Involcan) and ITER, in the optical fiber that is buried under the sea through the CanaLink network. Two of these were installed in 2018 on the fiber optic cable located between Tenerife and Gran Canaria. In recent weeks one has also been installed between the cable that runs between Santa Cruz de La Palma and the north of Tenerife. “With these DAS, the Canary Islands have become the place in the world best used with this new technology,” explains Villaseñor.
Between these facilities, however, there are differences. And it is that the DAS installed on land are more sensitive to earthquakes, while those found at sea also collect information on the noise made by ships or cetaceans.
