Hydrogeological Conditions of the Novobibeevo Occurrence of Radon Waters (The Novosibirsk Region)

Abstract

The first results of integrated geophysical and hydrogeochemical studies of the Novobibeevo occurrence of radon waters are presented for the first time. The object under investigation is situated at the contact zone of Upper Paleozoic granitoids and Lower Carboniferous - Upper Devonian rocks. Water composition is mainly HCO Mg-Ca with TDS 496 - 877 mg/dm and silicon content 5,8 - 13,3 mg/dm. Substantial variations were detected in the parameters of the geochemical medium (pH 6.6 - 7.5, Eh -81.2 - +212.7 mV; O 1.6 - 7.9 mg/dm). Radionuclides in the waters are of natural origin; their concentrations are (mg/dm): U from 5.25∙10 to 0.13 and Th from 1.86∙10 to 2.43∙10. The Th/U ratio varies within the range 2.63∙10 to 2.92∙10, with the average value equal to 4.24∙10. The activity of Rn in the wells varies from 4.0 to 167.5 Bq/dm. The studied waters are prone to anthropogenic pollution.