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Geophysical Workflows for Gold Exploration
Gold exploration programs often require more than one survey method to understand subsurface conditions. Geological mapping, geochemical data, drilling records, and geophysical measurements can each contribute to target selection and follow-up planning.
Electrical resistivity, induced polarization (IP), magnetic surveying, and transient electromagnetic (TEM) methods respond to different physical properties of the subsurface. When selected according to the geological model and expected target response, they can help exploration teams identify structures, electrical contrasts, magnetic anomalies, and areas that warrant further investigation.
Geomative Co., Ltd. provides geophysical equipment and related digital tools under its “Geophysics+” concept. Its product portfolio includes electrical resistivity and IP systems, power supplies, proton magnetometers, TEM instruments, and online-monitoring solutions.
GD-20 for Multichannel ERT and IP Surveying
The GD-20 is Geomative’s multichannel electrical resistivity and IP system for projects requiring multiple survey lines, broader area coverage, or improved field-testing efficiency.
The system uses an independent 5/12-channel design. Depending on survey mode and configuration, it can support up to 10 ERT acquisition channels and up to 12 sounding points. Geomative states that its average field-testing efficiency can be 2–3 times that of single-channel equipment under comparable conditions.
GD-20 supports self-potential, apparent-resistivity, and IP testing. Depending on the selected system configuration and survey layout, it can support relevant 2D, 3D, and pseudo-3D electrical survey tasks.
For gold exploration, ERT and IP data can help map electrical-property contrasts associated with geological structures, alteration zones, fractures, sulfide-related responses, or other anomalies requiring follow-up assessment. These results should be interpreted with geological mapping, geochemistry, drilling, sampling, and assay data.
High-Power IP Mid-Gradient Profiling
Geomative promotes a high-power IP mid-gradient profiling workflow that uses ERT modules for automated electrode selection during IP acquisition.
With appropriate cable deployment, transmitting electrodes and non-polarizable measuring electrodes can be arranged for lateral cross-sectional profiling. This can help teams collect IP information across planned survey sections more efficiently when site conditions and survey design are suitable.
The method should be evaluated according to target geology, electrode contact, line layout, environmental noise, available power, and the project’s technical requirements. High-power transmission and multichannel acquisition are components of survey design; they do not independently guarantee target depth, data quality, mineral discovery, or drilling success.
GD-10 for Targeted Electrical Surveys
The GD-10 is a single-channel electrical resistivity and IP system. Depending on the selected model and configuration, it can support electrical sounding and relevant 2D or 3D resistivity and IP survey tasks.
For a published gold-exploration case involving rock and quartz formations, Geomative’s GD-10 Supreme 2D+/3D+ was used with IP and ERT methods to assess chargeability and resistivity contrasts. The stated objective was to identify potential gold-related target areas for follow-up drilling and verification.
This is the appropriate role for geophysical surveys in gold exploration: providing subsurface data and target-prioritization evidence, followed by geological, drilling, sampling, and assay confirmation.
Magnetic Surveying for Appropriate Mineral Targets
The GPM-10 proton magnetometer can support total-field and gradient magnetic measurements. It uses an OCXO for time stability and supports GNSS, GPS, BeiDou, and GLONASS positioning and time synchronization.
Magnetic data can be useful where target geology or associated structures generate measurable magnetic contrasts. Geomative lists applications including iron, lead-zinc, and copper exploration. For gold exploration, magnetic surveying should be selected based on the local geological model, because not all gold deposits generate a diagnostic magnetic response.
TEM for Mineral and Deep Geological Investigation
Geomative’s GT-10 Mineral TEM system combines the receiver, transmitter, and power supply into a portable “one-box” instrument. It is positioned for mineral, groundwater, and geological-structure investigation.
The GT-10 product page lists a nominal detection range of 30–1300m. Actual investigation depth depends on target conductivity contrast, geology, terrain, survey design, environmental noise, and operating parameters.
For tunnel and non-coal mine roadway applications, the GT-20 Tunnel TEM system is positioned separately for advanced geological prediction before excavation. Method and instrument selection should follow the actual exploration or engineering objective.
Power Selection for IP and Resistivity Surveys
Electrical and IP survey power requirements depend on the measurement system, electrode layout, line length, ground resistance, target depth, site-power availability, and safety requirements.
Geomative’s BP-series DC power sources and GP-5000 high-power rectifier provide different field-power options:
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BP-450: Selectable 150V, 300V, and 450V DC output; maximum output current of 1A and maximum output power of 450W.
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GP-5000: Converts 220V AC input to continuously adjustable 0–1000V DC output, with a maximum output current of 5A and maximum output power of 5kW.
Power equipment should be selected based on compatibility with the measurement system and the actual project design. Higher output power alone does not determine investigation depth or interpretation quality.
Data Workflows and Monitoring Options
Geomative Studio supports electrical-survey workflow functions such as array configuration and survey-script preparation before field deployment. Following acquisition, data should be processed and interpreted using suitable software and project-specific geological evidence.
According to Geomative’s latest product information, DIGspace Geo-3D Platform is the company’s current digital data-platform direction. Its online-monitoring framework can support field monitoring equipment, data transmission, visualization, and configurable alerts.
For mining operations, online monitoring may be relevant to tailings facilities, dam safety, slopes, contaminated-site groundwater migration, and related environmental-management needs. It can support continuous data collection and remote review, but it does not replace engineering inspection, maintenance, or verification of abnormal readings.
Conclusion
An integrated geophysical workflow can help gold exploration teams combine complementary evidence:
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GD-20 for multichannel ERT and IP field acquisition;
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GD-10 for targeted electrical-resistivity and IP surveys;
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GPM-10 for magnetically responsive structures and targets;
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GT-10 TEM for relevant mineral and deep geological investigation;
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Project-appropriate power systems for electrical and IP field deployment;
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Digital tools for survey organization and relevant monitoring workflows.
The appropriate combination should be determined by the local geological model, expected target response, survey scale, terrain, available power, and the drilling-and-assay verification plan that follows geophysical interpretation.
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Geomative Co., Ltd.
