Applications of high resolution gamma ray spectroscopy to well logging

The PGT probe is a high resolution gamma ray spectroscopy tool that is effective for in-situ elemental analysis. Recent field studies in South Texas proved that this probe had particular application for borehole assay of uranium in orebodies that are in disequilibrium. Disequilibrium can cause severe difficulties in interpretation for the well log analysts using less sophisticated instrumentation. A californium-252 source is used with the probe in an active mode to produce gamma emissions from the elements of interest. In this mode, the PGT probe has been applied to the in-situ analysis of coal, iron and copper with interesting results. Results of the field trials are presented