EGU25-16037 | Orals | SM3.1

LOKI: A Field-Proven Optical Interrogator for High-Precision Remote Point Sensing of Electronics-Free Sensors, Now Available to the Geoscientific Community

Frédéric Guattari, Hippolyte Dupont, Philippe Menard, Pascal Bernard, Romain Ferron, Mathieu Feuilloy, Guillaume Savaton, Guy Plantier, and Jean-Philippe Metaxian
Mon, 28 Apr, 14:45–14:55 (CEST)   Room K2

LOKI is an optical interrogator initially designed at ESEO and progressively enhanced through several prototype generations. Over the last five years, these versions have been deployed globally in collaboration with IPGP, exploring a wide spectrum of sensing applications — from volcano surveillance to underwater seismic monitoring and geothermal studies. These field trials have confirmed LOKI’s robustness and revealed its potential for high-precision measurements.

From a technical standpoint, LOKI supports point-based optical sensing without the need for local electronics, even at distances of up to 30 kilometers along a fiber. This makes it especially well-suited for installations in remote or hazardous environments — such as undersea or volcano summit deployments — while keeping the interrogator safely located onshore. LOKI also serves as a complement to Distributed Acoustic Sensing (DAS) technologies, which provide continuous measurements along the fiber itself. The integration of DAS and LOKI allows for both broad spatial sensing and high-resolution, localized data collection — ideal for complex experimental setups.

The talk will showcase several field deployments and real-world applications where LOKI has demonstrated its versatility. Designed for autonomous outdoor operation, the system consumes only 6 W and can run on a small solar panel. Its fully optical and maintenance-free sensing elements — including fiber-based strainmeters and seismometers — are already in use, with other capabilities in development, such as rotational sensing. Additionally, the possibility of retrofitting traditional seismometers for optical readout will be discussed, expanding the reach of remote, fiber-based interrogation systems.

Today, LOKI is commercially produced by MAÅGM, ensuring reliability, scalability, and ongoing technical support. This presentation aims to share lessons learned across diverse field campaigns and to inform researchers that these tools are now mature, reproducible, and ready to support next-generation seismic and structural monitoring.

How to cite: Guattari, F., Dupont, H., Menard, P., Bernard, P., Ferron, R., Feuilloy, M., Savaton, G., Plantier, G., and Metaxian, J.-P.: LOKI: A Field-Proven Optical Interrogator for High-Precision Remote Point Sensing of Electronics-Free Sensors, Now Available to the Geoscientific Community, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16037, https://doi.org/10.5194/egusphere-egu25-16037, 2025.