Direct determination of geochronologically useful radionuclides in sediments by low-energy photon analysis

Low-energy gamma-ray spectrometry is used for the nondestructive determination of 210Pb, 226Ra and 241Am in sediments. The self-absorption of the low-energy gamma rays is corrected using a technique involving direct gamma transmission measurements on sample and efficiency calibration standard. Several reference materials when analyzed by the described technique gave values similar to those obtained by other techniques. The utility of the technique is illustrated through the analysis of excess 210Pb and fallout 241Am profiles in two sediment cores from Great Slave Lake, NWT, Canada. It is proposed that simultaneous 241Am measurements provide an attractive alternative to the conventional measurement of fallout 137Cs profiles. (orig.)