What geophysical technique is most suitable for investigating a skarn?

The most suitable geophysical technique for investigating a skarn is magnetics. Skarns are typically formed at the contact zones between igneous intrusions and carbonate rocks through the process of metamorphism and chemical alteration. These processes often lead to the formation of minerals that exhibit distinct magnetic properties.

Magnetic surveys can effectively identify the presence of these minerals, as variations in magnetism can indicate the composition and structure of the underlying geology. Skarns often contain magnetite and other magnetic minerals, making magnetic methods adept at locating and delineating skarn deposits. The ability to analyze the presence of such minerals provides important insights into their extent and distribution.

In contrast, while seismic reflection and refraction are valuable techniques for subsurface imaging and mapping geological structures, they are not as specifically tailored to detecting skarns, which require attention to the magnetic signatures resulting from mineral alterations. Gravity methods, on the other hand, measure variations in gravitational pull based on density differences but may not provide the specific insights needed to explore skarn formations like magnetic surveys can.