An even simpler approach is to use a table or chart of exploration depths attained in common materials. An example chart for common materials encountered with GPR is shown in Figure 5. As Figure 9 demonstrates, material alone is not a true measure of exploration depth. Material type can be seen to control exploration depth. Unfortunately, exploration can not always be predicted by knowing only the material in the survey area.
Data shows response of barrels in wet, silty clay.
Figure 9 shows a section where the geology is basically uniform but the depth of exploration is highly variable. In this case, knowing conductivity provides a better measure of exploration depth than knowing the material. Depth of exploration is determined by pore water conductivity-not the sand material.