SGM operates a Radio Imaging Method (RIM) product line of geophysical detection and mapping equipment. The RIM-6 system is SGM’s latest and most advanced instrument version of RIM technology and is the end-result of a four-year development program and a follow-up to the successful RIM-4 and RIM-5 systems. RIM-6 was introduced in 2011 and has been used continuously in both Australian and American mining operations to date with incredibly high performance gains. Specifically, RIM-6 provides a 20 to 40 dB improvement in signal-to-noise ratio (SNR) over RIM-4 and allows for the use of much higher imaging frequencies (increased sensitivity and resolution) and longer transmission distances (increased range and scope of surveying).

Available in both hand-held and borehole versions, RIM-6 is typically used as a means of interrogating geological conditions ahead of mining. Handheld RIM-6 is typically used between drives/headings/entries in underground mines. Borehole RIM-6 technology can be utilized in both vertical and horizontal borings of at least 2-inch (50mm) diameter, regardless of borehole depth.

The RIM technique utilizes medium-frequency radio-wave transmission to map variations in geologic conductivity between a transmitter and receiver (as well as geologic structure). The principle key to RIM-6 success is the narrow band-width and wide dynamic range of its receiver (RX), which provides greater detection sensitivity and a lower noise floor than any previous RIM system. The fully digital RIM-6 receiver provides: (a) more stable and accurate measurements, (b) wide-band spectral noise analysis, (c) multi-channel, multi-frequency measurements, and (d) two-way transceiver functionality. A secondary contribution is in the improved transmitter (TX) antennas which generate larger moment magnitudes and couple greater signal into the geology. These improvements provide greater operational range and improve resolution. In addition to improved RF performance, the current RIM-6 hardware uses modern PDA and Bluetooth technology as the primary command and control interface, increasing data rates, and utilizing wireless communication and onboard data storage/processing. The TX and RX units are not connected by any type of cable or wire, but rather, utilize wireless synchronization.

RIM-6 Instrumentation Systems:

There are three primary RIM-6 packages: Borehole Systems, In-Mine Systems, and Specialty Systems. SGM’s RIM systems were developed to match a wide variety of logistical, environmental, and site-specific conditions. Additionally, all systems are inter-compatible making it possible to combine multiple survey techniques.

Borehole Systems. Borehole systems include a variety of motor-powered and hand-powered hoist and fiber optic spool systems capable of lowering instruments to depths of 5,000 feet (1500 meters).







In-Mine Systems. Hand-carried transmitter (TX) and receiver (RX) antenna and electronic packs have been designed and constructed to be relatively light-weight, self-powered, and compact. The largest components, the air-core antennas, measure less than 30″ diameter so as to pass through the man-doors commonly found in underground mines. Even within the protective storage cases, the antennas are easily transported via underground mine vehicles.









Specialty Systems. Unique and cutting-edge instrumentation is currently in prototyping development stages to further advance the field services capabilities of Stolar Global Mining (SGM). Furthermore, for unusual or particularly difficult job requirements, SGM has the ability to design and build custom RIM systems for clients.





Note: SGM’s RIM-6 systems are designed and built for the exclusive use of its field service organization and its highly trained technical and geophysical staff. The instrumentation is intended to provide the geophysical data needed to generate RIM reconnaissance and tomography deliverables as a part of its field service and consulting operations. RIM instruments are not typically offered for sales or lease. Some exceptions may be possible; contact SGM for more information.

About RIM, the Radio Imaging Method:

RIM instruments send radio waves through the rock/coal, reacting to geologic layering, composition, structure and void-space. RIM data used to generate tomographic images to predict properties of host media and identify geologic structures.
RIM is applicable to most geological or geotechnical imaging applications include coal mining, hardrock and metalifferous mining, environmental remediation, and civil engineering. Layered stratigraphies can create natural waveguides for low-frequency electromagnetic waves making RIM more effective in layered geology, although layers are not required.
RIM generates images of the geology between adjacent drillholes or entries; better detecting areas of high geological risk or delineating areas of clean coal or mineralization. RIM surveys provide added value to exploration drilling by imaging between existing boreholes, and ahead of mining.











RIM can improve resource evaluation and mine planning by:

  • imaging between exploration boreholes, better delineating structure
  • navigating around areas of geologic anomaly or mining hazard

RIM is an Electromagnetic Radio-Wave TRANSMISSION method; TX and RX are separated – RIM is not “Ground Penetrating Radar”
RIM utilizes a Quasi-TEM mode signal propagation for RF frequencies in and below the AM Band (low to mid-frequency range). This method generates radio-wave signal attenuation rates and phase shifts unique to the geologic conditions.

Radio Imaging Method brings more than Core,
and more than conventional E-Logging.

SGM’s Qualifications:

Radio Imaging Method (RIM) technology has been used commercially for over three decades. Stolar pioneered the theory and technology behind RIM and is the unique sole-proprietor of radio geophysics world-wide. The SGM field survey team has considerable experience, having performed over 1000 surveys under many different conditions and applications.
Radio imaging also has a long history with national laboratories and universities in the USA, Australia, and Russia (LANL, SNL, CSIRO, and NIIS). RIM-2 was developed and tested with international cooperation in engineering and electronics, RIM-3 benefited from improved antenna design and CPU upgrades through national lab cooperatives, and RIM-4 was developed and demonstrated in the USA under the Department of Energy (DOE)/National Mining Association (NMA) Mining Industry of the Future Program and has been tested extensively for abandoned and water-inundated old-mining works by MSHA and NIOSH. RIM-4 was tested in Australia as a CSIRO project. RIM data processing was improved by the development of Full-Wave Inversion Code tomography software developed by LANL scientists and was the first of its kind for inversion processing of full phase-coherent radiowave data sets on a large scale.
SGM maintains an exclusive field-of-use license for all Stolar RIM instrumentation and currently maintains R&D and manufacturing capabilities for RIM product-line expansion, system upgrades, and specialized customer modifications. The Radio Geophysics Division has continued to improve the form and function of Radio Imaging Method (RIM) instrumentation while continuing to perform commercial field surveys throughout the world and across several industries and a broad range of applications. The goal of RIM development has been to provide tools that generate geophysical data with greater sensitivity, range (distance), and flexibility over existing RIM instrumentation. In concert with this objective is the belief that the instruments should be easy to operate, maintain, and should leverage new advances in data processing, storage, and wireless communications.