Method for in situ evaluation of the source rock potential of earth formations
 A technique for the in situ evaluation of the organic carbon content of earth formations penetrated by a well borehole is disclosed. The energy spectrum of natural gamma radiation occurring in earth formations penetrated by a well borehole is observed in energy regions corresponding to uranium, potassium and thorium. Quantitative evaluations of the relative abundances of these elements are made by comparing the observed spectra with standard gamma ray spectra. The relative abundances of these elements may then be interpreted in terms of the organic carbon content of earth formations by comparison with predetermined relationships found to exist therebetween. 
Texaco Inc.
G
G01V
inventional
Irwin R. Arthur Jurgen Dan McCay
Supernaw Link Arnold