01Questions to define first
Before selecting a method, establish the target, geological setting, decision threshold and what information can realistically discriminate between alternatives. Remote sensing, geophysics and field observations each have different resolution, coverage and interpretation limits.
- What decision should the information support?
- What survey, sampling or geological data are available?
- How were the data acquired, processed and interpreted?
- What independent checks or field evidence are appropriate?
Method selection depends on project context, data quality and qualified technical review.
02Satellite, UAV and spectral image analysis
Satellite imagery may frame broad-area patterns; spectral and hyperspectral image analysis adds information about how materials reflect visible and infrared wavelengths. GIS brings imagery together with mapped geology, topography, geophysics and sampling. Where project needs and acquisition conditions suit, UAV imagery may support closer local follow-up at a resolution suited to the target. A review asks whether coverage and resolution fit the target, how patterns relate to known geology, and where field checks would change the interpretation. Interpret image data alongside geological context and field validation.
03Alluvial and riverbed investigation
Bathymetry maps water depth and bed-surface shape in plan view; sub-bottom profiling (SBP) can add cross-sections of acoustic reflectors below the bed, such as sediment boundaries or sediment/rock contacts, where signal penetration and data support interpretation. In alluvial settings, target interpretation considers bedrock depressions, bars, bends, confluences, pools, eddies and changes in river gradient alongside channel geometry and geological context. A useful survey question is whether profiles cover the relevant reach and how the interpretation can be checked against sampling, pitting, drilling or other field observations. This connects the shape seen in a profile to evidence that may support or challenge a target model.
04Ground geophysics and verification
Ground geophysical interpretation depends on the geological setting and known control data. For hard-rock structures, profiles need to be interpreted alongside available geological and drilling data; alluvial targets instead focus on riverbed and sediment geometry. In both settings, define the calibration data, survey coverage, assumptions and independent checks before using profiles to guide the next decision. A geophysical profile informs interpretation; by itself it does not establish a mineral resource or replace appropriate technical sign-off.
05Resonance Acoustic Penetration (RAP) Profiling
MinEx technical material describes RAP as land-based profiling that interprets acoustic responses recorded at stations against known geological, drilling or pitting controls to develop profile cross-sections. The material discusses alluvial and hard-rock settings. RAP differs from underwater sub-bottom profiling (SBP), which describes reflectors below the riverbed. The May 2020 paper reported that RAP had not then been commercially developed and proposed trials; current availability, suitability and validation status should be confirmed for any specific application.
If exploration evidence informs a wider decision about project options or economics, see overall project assessment.
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