New opportunities for seismologists, With glass-fiber cables in front of the glacier crashes warnenETH-researchers took on the Rhone glacier, a new Instrument, the ice masses listen in. Even glacier crashes can be possibly sometime early predictions.0 KommentareDie seismologists carried out their measurements at the Rhone glacier at a height of 2500 metres.Patrick Paitz / ETH Zürich

fiber-optic cable to provide seismologists with new ways to the Interior of glaciers communicates to Shine through, such as the Swiss national science Foundation (SNSF).

until now, only few measurement networks to monitor the movements of glaciers on a large scale exist. Because the Installation of the Seismometers, which register the smallest movements in the underground, in remote mountain regions-consuming and expensive.

researchers from ETH Zurich took on the Rhone glacier, now a new Instrument, the ice masses listen: It is the glass fiber cable, such as the SNF announced on Friday. “While the establishment of a seismic station that only covers a tiny glacier area, often several hours are required, rolled out a fiber-optic cable with hundreds of Sensors easily. So the whole glacier, can theoretically monitor”, was the seismologist Fabian Walter in the message quote.

Smallest bumps

to demonstrate functioning How well the glass seismometers, revealed a field campaign on the Rhone glacier in March 2019. The research team led by the ETH professors Fabian Walter and Andreas Fichtner buried the hair-thin cable with a total length of one Kilometer, a few inches deep in the Snow cover of the glacier.

With the cable they shot laser pulses. These light signals are reflected back to naturally occurring impurities in the Interior of the glass fiber cable. Now, if the smallest vibrations stretch the cable or compressing, changing the way the reflected light. Using this time shift, the researchers recorded the smallest movements in the glacier.

Jerky movements

in Particular, rockfalls and Eisbeben were able to locate the glaciologists much more precise than with seismometers. In addition, they detected jerky motion at the glacier bed, which are already known from the Greenland and Antarctic Ice sheet and could now be shown for the first time in the Alps clearly. The results of this appeared in the journal “Nature Communications”.

new Monitoring by means of fiber optic cables is not: for Example, scientists measure the seismic activity on the sea floor. Also in various big cities, seismological work, lying on it, the existing glass fiber cables for telecommunications for earthquake monitoring. The geophysicist Fabian Walter of the SNF-communication, but one of the first to use this technique on glaciers.

Looming glacier crashes

Due to the warming of the climate monitoring threaten to thunder in many mountain regions, glaciers masses in the valley. Such a Numerous occurred, for example, in the fall of 2017 at the trift glacier in the Valais SaaS valley, as an unstable glacier tongue broke off.

“in the Future, we want to monitor with glass-fiber cables, such events are targeted,” said Fabian Walter, at the request of Keystone SDA. Because the glacier was dismembered to crash vulnerable, however, and rugged, the signals are much less clear than on the flat Rhone glacier. Currently, the Glaciologist, working with data from the Eiger glacier crash because the monitoring technology is advancing.


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