The material being surveyed, and the antenna frequency being used is what determines how deep the GPR can penetrate. Ice, rock, soil and asphalt, for example, all have different electrical properties and are all penetrated differently. However, the further we go, the more frequency is lost. This loss in frequency causes a loss in resolution.

When it comes to soil, the condition of the soil affects the penetration level. Dry and sandy soils with little salt tend to return the best survey resolution, while heavy clay-based soils can be difficult. The difference could be up to 10m between a dry soil and a clay-based soil.