GRS is the only provider of MIMDAS Technology and was the first geoelectric system to be built and developed in a distributed acquisition framework. This particular design confers a unique flexibility which translate in a variety of methods that can be surveyed by our receivers like resistivity/IP, AMT, CSAMT, EM, in 2D lines or real 3D arrays. MIMDAS has more than 200 channels with 24 bits each. MIMDAS was also the first system capable to quantitatively, calculate and remove the telluric noise in real time and also implement inhouse digital signal processing custom algorithms which made MIMDAS data a superior standard capable to read IP response in a microvolt range. Currently, GRS has operating crews in Chile, Australia and before long, Perú.

GRS uses MIMDAS system to acquire MT data with a capacity of up to 200 channels using EMI BF-4 or Zonge ANT-4 coils. Routinely MT data is acquired in EMAP configuration and TM mode. This configuration has important benefits like improving horizontal resolution and reducing the static shift effects. The impedances curves obtained using MIMDAS equipment have more point per decade that common equipment within 0.006 and 400 Hz bandwidth. Results obtained from a comparison of MT and DC resistivity inversion model shown commonly a good agreement in both methods in most of the cases and where difference arise both methods complement the information about the resistivity response of the ground. .

GRS has an advance method to telluric correct the IP signal, boosting the s/n ratio five times or more, allowing to acquired data in the microvolt range with great confidence. Also, MIMDAS system enable to set the receivers in variety of configuration from 2D to real 3D arrays. The depth of investigation, with this method, depending on data quality and array used, could reach depths of 1000 m or more.

MIMDAS system can be used to acquire conventional IP data in areas that need a limited depth of investigation with shallow structures in a range of hundreds of meters.

GRS uses GEM-19, mobile and base station, to survey the magnetic field variations. This method has been widely applied in Chile and Argentina by GRS team.

GRS routinely uses state of the art codes that enable us to provide our clients inversion models with a superior resolution of the geophysical variable been studied, like, for example, adjoint MT+DC or CSEM inversions. This last point is a particularity of MIMDAS system that allows to acquire data in time and frequency domain, simultaneously. This method contributes, among other things, to use the EM coupling as part of the solution of IP response and not part of the problems as commonly this effect is assessed in IP surveys. The experience gathered by our geophysical team among over these years working in different geological environments and seen a variety of earth responses that we could contribute to integrate and interprete the results to the benefits of our clients.

GRS has an extensive experience in software development having implemented the MIMDAS operative system and other codes like inversion/forward modelling, data QC and data visualization codes. This are some of the software developed by GRS.