Relatively recently, it became clear that conventional fiber optic cables can work as seismic activity sensors. The fluctuations of the earth's crust affect the cable laid in the activity zone and cause deviations in the degree of scattering of the light beam in the waveguides. The equipment picks up these deviations and identifies them as seismic activity. In experiments set a year ago, for example, with the help of fiber-optic cables laid in the ground, even the steps of pedestrians were recorded.
It was decided to check this feature of optical cables to assess the behavior of glaciers - this is where the field is not plowed. Glaciers themselves serve as indicators of climate change. The area, volume, and movement (faults) of the largest glaciers on Earth provide valuable information for long-term weather prediction and for forecasting climate dynamics. The only bad thing is that tracking glaciers with traditional seismic equipment is expensive and not available everywhere. Will fiber optic cables help with this? Experts from the Swiss Federal Institute of Technology Zurich (ETH Zurich) tried to answer this question.
A group of scientists led by Andreas Fichtner, professor at the ETH Zurich Laboratory of Hydraulics, Hydrology and Glaciology, went to the Rhone Glacier. In the course of the experiments, it turned out that fiber optic cables are more than excellent tools for capturing seismic activity. Moreover, the cable laid on snow and ice, under the heating of the sun, melted into the ice itself, which is absolutely necessary for the operation of such a network of sensors.
The created network of sensors with vibration fixation points with a step of only one meter along the length of the cable was tested by a series of explosions simulating faults in a glacier. The results obtained exceeded all expectations. In this way, scientists may soon have tools in their hands that will help track glaciers with a high degree of accuracy and warn of earthquakes in the early stages of earth's crustal activity.
Source: 3dnews.ru