Mineral exploration geophysics focuses on detecting, mapping, and characterizing economic mineral deposits and geological structures that control ore formation. Modern exploration programs integrate geophysics, remote sensing, structural geology, and geochemistry to reduce drilling costs and increase discovery success.

Exploration Objectives

Mineral and natural resource geophysics aims to:

1 Identify and map mineral deposits

  • Metallic ores (Cu, Pb, Zn, Ni, Au, Ag)
  • Industrial minerals (limestone, gypsum, phosphate, kaolin)
  • Rare earth elements (REE)
  • Energy-related resources (uranium, coal, geothermal)

2 Define geological structures

  • Faults, shear zones, folds
  • Dikes, intrusions, and volcanic features
  • Basin architecture and lithological contacts

3 Reduce exploration cost

  • Prioritize drilling locations
  • Avoid non-productive excavation
  • Map ore extensions and continuity

4 Map natural resource distribution

  • Quarry materials (rock quality, extent, purity)
  • Construction aggregates
  • Groundwater in mining areas
  • Geothermal zones and heat anomalies
  • Clay, sand, and industrial rock deposits

Mineral Exploration Geophysics

Geophysics guides mineral discovery, reduces drilling costs, and helps define mineable resources.

Key Applications

A. Metallic Minerals

  • Copper, Lead, Zinc, Nickel
  • Detecting conductive sulfides (IP, EM, VTEM)

B. Precious Minerals

  • Gold-related structures
  • Intrusive bodies and shear zones

C. Industrial & Strategic Minerals

  • Iron ore, Phosphate, Bauxite
  • Rare Earth Elements (REE)

D. Geological Mapping

  • Faults, lineaments, dykes
  • Lithological contacts

Natural Resource Mapping

Applied geophysics also supports mapping of non-metallic resources used in construction, agriculture, and industry.

Industrial Rocks & Minerals

  • Limestone, dolomite, gypsum, phosphate: resistivity & seismic
  • Granite & basalt quarries: seismic + magnetic + GPR
  • Clay deposits: ERT + VES + radiometric surveys

Natural Aggregate Mapping

  • Identify gravel/sand thickness and quality
  • Delineate deposit boundaries
  • Estimate extraction volume

Geothermal Resource Mapping

  • Thermal gradient measurements
  • Resistivity surveys for geothermal reservoirs
  • Magnetotellurics (deep conductivity)

Natural Hydrocarbon Indicators

  • Microseep detection
  • Structural mapping with magnetics & gravity
  • Shallow seismic for stratigraphic traps

Deliverables in Mineral Exploration & Resource Mapping

  • 2D/3D geophysical models (IP, EM, resistivity, magnetics, gravity)
  • Structural lineament maps
  • Alteration mineral maps (remote sensing)
  • Orebody targeting and ranking
  • Drill collar recommendation maps
  • Resource estimation support maps
  • Quarry feasibility studies
  • Mineral prospectivity modelling
  • Integrated geological–geophysical interpretation reports

Key Geophysical Methods in Mineral Exploration

Induced Polarization (IP) & Resistivity

Theory

  • Measures chargeability caused by metallic particles (sulfides).
  • Resistivity highlights contrasts between host rock and mineralized zones.

Applications

  • Discovery of disseminated sulfides (Cu, Pb, Zn, Ni)
  • Mapping orebody geometry and depth
  • Identifying alteration halos
  • Prioritizing drill targets

Magnetic Surveys

Theory

  • Detect variations in magnetic susceptibility of rocks.
  • Identifies structures controlling mineralization (faults, dikes, shear zones).

Applications

  • Iron ore mapping
  • Structural mapping in gold fields
  • Mafic/ultramafic intrusions (nickel exploration)
  • Mapping lithological contacts and geological boundaries

Gravity Surveys

Theory

  • Measures density variations in the subsurface.
  • Sensitive to massive sulfide bodies and basin architecture.

Applications

  • Detect dense massive sulfide ore
  • Structural mapping in large terrains
  • Basin depth mapping (uranium, coal)
  • Salt dome exploration

Electromagnetic (EM) Surveys

Theory

  • Measures ground conductivity and EM induction response.

Applications

  • Detecting conductive ore bodies (graphite, sulfides)
  • Mapping groundwater in mining areas
  • Identifying alteration zones associated with mineralizing fluids
  • Rapid regional exploration (airborne EM)

Radiometric / Gamma-Ray Spectrometry

Theory

  • Measures natural gamma radiation from K, U, Th.

Applications

  • Uranium exploration
  • Mapping alteration minerals (potassic alteration, clay zones)
  • Lithological and soil boundary mapping
  • REE exploration

Seismic Methods (Hard-Rock Reflection)

Theory

  • High-resolution seismic imaging detects deep structures, faults, and lithological contrasts.

Applications

  • Mapping ore-controlling faults
  • Deep orebody imaging
  • Mine planning & resource estimation
  • Hard-rock structural mapping

Remote Sensing for Mineral Mapping

Theory

  • Uses multispectral and hyperspectral satellite imagery to identify mineral-specific absorption features.

Applications

  • Hydrothermal alteration mapping (clays, carbonates, iron oxides)
  • Lithological classification
  • Structural interpretation (lineaments, fractures)
  • Target generation for ground geophysics