Measurement of distribution of rare earth elements in Arima-type springs using preconcentration with chelating resin/ICP-MS

Abstract

Rare earth elements (REEs) in Arima-type spring waters were detemined by ICP-MS after pre-concentration with a chelating resin. Our previously reported method was improved by washing the chelating resin with 5 M HCl over night and then removing the mass interference of Ba to Eu-151. The concentrations of REEs in a hot spring of high Cl content are relatively low compared with a low temperature spring of high Cl and CO₂ contents. The correlation of all the REEs concentration, except for the Eu and CO₂ concentration, were found in Arima spring water samples. Thus the carbonate species plays an important role in the REEs contents in these Arima spring water samples. From the chondrite pattern of the REEs, a positive Eu anomaly was observed in all hot spring samples of high Cl and Fe contents in the Arima region. Also the concentration of Eu was correlated with the K concentration in the Arima spring water samples. Eu in spring water was stimulated to be dissociate into the Eu²⁺ ion from the feldspa of wall-rock by a hot water/rock interaction at reduction situation.