Nowadays scientists pay more attention to the process of Alpine microseismicity. The thing is that the sensing of seismic activity is important for studying landscape-shaping processes and predict dangerous mass movements. Nonetheless, the amount of modern fiber optic sensors is still low in Alpine regions. Therefore, distributed acoustic sensing (DAS) promotes solving the problem.
The application of advantageous fiber cables makes DAS technology very promising in seismic monitoring of glacier movements and natural hazards. Additionally, DAS technology has significantly changed the portability of seismic devices. This is why the performance of seismic monitoring in difficult-to-reach areas becomes more and more accessible.
It should be noted that the purpose of distributed acoustic sensing “focus on processes near the Earth’s surface rather than on traditional seismology subjects like the deeper crust and mantle.” DAS applies fiber optic sensors into which an interrogator enters a sequence of laser beam pulses. Herewith, fiber optic systems as distributed acoustic sensing are widely used in geophone chain deployments.
Fiber optic systems allow for sensing local earthquake signals, which are too weak to be recorded by conventional seismometers. Moreover, DAS enables the record of anthropogenic noise. Even though individual channels of distributed acoustic sensing have some disadvantages as a lower signal-to-noise ratio, they overcome seismometers. The thing is that there are a lot of unused fiber optic systems with unprecedented sensor coverage and density.
Novel DAS technology performs the records of microseismic signals and ambient noise in glacier areas. Compared to standard fiber optic systems, new distributed acoustic sensing offers important improvements in stick-slip event location and determines weak seismic waves. Herewith, the potential and utility of DAS systems are doubtless for sensing glacial processes.
According to scientists, DAS technology performs measuring seismogenic glacier flow and even small Alpine mass movements, for example, rockfalls. The benefits of distributed acoustic sensing include better limitation of static and dynamic properties of the glacier and its surroundings. The most significant thing is DAS technology provides precise arrival time measurements despite spatial averaging.
Finally, the advantages of DAS channels increase the location quality of stick-slip events significantly. The density of distributed acoustic sensing detects numerous reflections and extremely refracted waves. Herewith, spaced seismometer networks can not carry out it.
Optromix is a DAS system manufacturer that provides top of the line distributed acoustic sensing systems suitable for monitoring commerce networks. If you have any questions or would like to buy a DAS system, please contact us at info@optromix.com