Uranium geochemical survey in Northewestern Leyte

Stream sediment uranium geochemical survey was undertaken in Calubian peninsula in Northwest Leyte island. A total of 174 stream sediment samples and 110 heavy mineral panned concentrates were collected along the streams draining about 540 sq km area. The minus 80 mesh fractions of the sediments and non-magnetic mineral concentrates were analyzed for total uranium employing instrumental delayed neutron activation analysis (DNAA) technique. The results indicated that the uranium concentrations in the stream sediments ranged from 0.8 ppm to 5.2 ppm while that of the heavy metals ranged from 0.2 ppm to 65.3 ppm U. The background and threshold values for the stream sediments were 1.7 ppm U and 2.9 ppm U, respectively, while the corresponding concentrations for the heavy minerals were 2.6 ppm U and 26.2 ppm U, respectively. Based from these results, two prospective heavy mineral anomalies were detected in Villaba (Cebongaga) and Palompon (Kampisao). The Villaba and Palompon anomalies are related to the Lower Miocene Taog Formation. Other geochemical anomalies were also found but these were mostly point anomalies and were not considered encouraging signs of possible uranium mineralization. (author). 9 refs.; 2 figs.; 3 tabs