Rare Earth Elements behaviour in different types of mineral waters within Baikal Lake

Abstract

The current study contains a review of the REE abundance and distribution in thermal and cold mineral waters which are widely spread around Baikal Lake. Studied mineral waters were divided into CH4, N2 and CO2-rich waters by the associated gas composition. We found that the highest REE concentrations were connected with thermal waters that were accumulated in swamps (slow-moving waters). Another core process for accumulating of REE in waters is the rock weathering in CO2 presence. This study shows that there are no correlations between REE and main ions, Eh, TDS and temperature. But dependence of REE on pH and positive correlations of REE with Al, P, Mn, V, Cu, Pb and As, which indicate common processes of microelements migration, were established. Within the study waters the light REE concentrations dominate over heavy REE. The presence of CO2 gas increases heavy REE concentrations, and concentrations of several light elements (La, Ce, Nd). The observed differences in REE contents in studied waters can be provenance dependent and possibly relate to more complicated evolutionary processes as water circulation time, depth and mixing. This is the first investigation of REE distribution and abundance in mineral waters of the Baikal Lake.