OUR EXPERTISE
At Nāga Geophysics we implement the latest scientific advances in geophysical imaging. The fundamental knowledge acquired through our proximity to the Research and Academic world enables us to offer innovative solutions.
Our team intervenes on the most difficult sites to access, thanks to a great experience of high mountains and remote sites. We develop our own algorithms to take into account complex geometries and to adapt data processing to the specificities of each site.
NATURAL HAZARDS
Landslide
Nāga Geophysics implements the induced polarization method to calculate and characterize underground parameters in terms of water content, clay content (CEC, cation exchange capacity) and permeability. These parameters make it possible to locate zones with the highest risk of landslides.
Setting up instrumentation on sensitive sites makes it possible to detect changes that are precursors to landslides, for early warning purpose.
Permafrost
Nāga Geophysics contributed to the development of new equations for the interpretation of geoelectrical measurements on permafrost sites.
This innovative method, based on induced polarization, allows adapting the establishment of high mountain infrastructures.
INFRASTRUCTURE AND FACILITIES
Leak diagnosis
Nāga Geophysics' unique expertise has enabled us to develop innovative solutions for detecting leaks in embankments and dams.
Based on the induced polarization method, water content imaging is a powerful tool for the diagnosis of civil engineering structures and for the monitoring of their integrity over time.
The adjacent 3D model illustrates the implementation of this method in the framework of a partnership between André REVIL and the IRSTEA (now INRAE) on a test site in Aix-en-Provence.
Water content and clay content
Nāga Geophysics also implements the induced polarization method to calculate the water content and clay content (CEC, cation exchange capacity) to obtain a complete diagnosis of civil engineering structures.
The adjacent water content and cation exchange capacity sections were obtained from measurements taken on the surface of an embarkment.
Geomembrane inspection
In collaboration with André REVIL, Nāga Geophysics is developing specific expertise for the inspection of geomembranes. The progress achieved on the grounding method allows the precise localization of leaks. It can be implemented on full reservoirs, for example, for leachate basins or for reservoirs used by ski resorts for artificial snow.
References:
Ling C., A. Revil, F. Abdulsamad, Y. Qi, A. Soueid Ahmed, P. Shi, S. Nicaise, and L. Peyras, Leakage detection of water reservoirs using a Mise-à-la-Masse approach, Journal of Hydrology
Ling C., A. Revil, Y. Qi, F. Abdulsamad, P. Shi, S. Nicaise, and L. Peyras, 2019. Application of the Mise-à-la-Masse method to detect the bottom leakage of water reservoirs, Engineering Geology
SITES AND GROUND CONTAMINATION
Monitoring of artificial wetlands
The implementation of induced polarization on wetlands, combined with a specific processing algorithm, makes it possible to obtain a 3D image of the clogging of filters.
Instrumentation of this type at wastewater treatment sites makes it possible to locate areas requiring preventive measures. 4D acquisition (3D repeated over time) is a powerful tool for monitoring sites and optimizing their performance.