Which geophysical technique would NOT be useful for investigating a massive sulfide ore body?

Seismic refraction is not particularly effective for investigating a massive sulfide ore body due to the nature of the seismic waves and the characteristics of sulfide minerals. Massive sulfide ores typically have a density and acoustic impedance that can differ significantly from surrounding rock, potentially leading to less distinct seismic reflections or refractions. While seismic methods are powerful tools in geological exploration, they are generally more suited for imaging larger structural features or interfaces in the subsurface, rather than detecting smaller, more localized ore bodies that may not generate strong seismic signals.

In contrast, gravity, induced polarization, and resistivity techniques are better suited for targeting massive sulfide deposits. Gravity surveys measure the variations in gravitational attraction due to density differences, helping to identify dense ore bodies like sulfides. Induced polarization measures how the material responds to an alternating electric field, which is particularly effective for sulfide minerals due to their electrical properties. Resistivity techniques help differentiate between conductive and non-conductive materials, with massive sulfide ores often exhibiting significantly lower resistivity than surrounding sediments or rocks. Thus, the strengths of these methods make them more appropriate for targeting and investigating massive sulfide ore bodies.