What type of geophysical exploration would you use to delineate an ore body containing hematite and chalcopyrite?

What type of geophysical exploration would you use to delineate an ore body containing hematite and chalcopyrite?

• A. Seismic reflection.
• B. Magnetic survey.
• C. Electrical resistivity tomography.
• D. Ground-penetrating radar.

Answer: (B)

Magnetic methods rely on contrasts in magnetic susceptibility to reveal subsurface bodies. An ore body rich in hematite brings higher magnetic response than surrounding rocks, so it creates a detectable magnetic anomaly at the surface. Chalcopyrite itself isn’t strongly magnetic, but the hematite and related iron-oxide minerals in the ore body provide the magnetic contrast that helps delineate the ore’s shape and extent. Seismic reflection maps boundaries and rock properties but doesn’t directly reveal mineralogy, electrical resistivity tomography depends on electrical contrasts (and sulfide ores can be conductive, though not as consistently as magnetic contrasts), and ground-penetrating radar works best for shallow, high-resolution imaging near the surface. In many hematite-bearing ore settings, the magnetic anomaly offers the clearest, most efficient way to outline the ore body.

Magnetic methods rely on contrasts in magnetic susceptibility to reveal subsurface bodies. An ore body rich in hematite brings higher magnetic response than surrounding rocks, so it creates a detectable magnetic anomaly at the surface. Chalcopyrite itself isn’t strongly magnetic, but the hematite and related iron-oxide minerals in the ore body provide the magnetic contrast that helps delineate the ore’s shape and extent.

Seismic reflection maps boundaries and rock properties but doesn’t directly reveal mineralogy, electrical resistivity tomography depends on electrical contrasts (and sulfide ores can be conductive, though not as consistently as magnetic contrasts), and ground-penetrating radar works best for shallow, high-resolution imaging near the surface. In many hematite-bearing ore settings, the magnetic anomaly offers the clearest, most efficient way to outline the ore body.