Gamma Radiation emanates from naturally-occuring radioactive elements in earth materials (primarily Potassium 40 and Uranium daughter products). Higher concentrations of such elements tend to occur in finer grained sediments, allowing clays to be readily differentiated from sands.
ESN uses the world's first true SlimLine Gamma Logger (0.75" O.D. x 24" long) in open holes, miniwells, MegaprobeŽ pipe, or existing wells. As with any logging tool, the first step is to calibrate the response to local lithologic conditions in existing holes or by a continuously cored hole on-site.
Carefully compare lithologic/soil character to gamma response and use that as a model for further holes. The logger works in saturated or unsaturated conditions, and only takes a few minutes. A field log is stored on a PC and printed on-site. Final logs and intrepretive results are available.