Dolomitization of limestone with MgCl₂ solution at 150°C: Preserved original signatures of rare earth elements and yttrium as marine limestone

抄録

We have studied the mobility of rare earth elements (REE) and yttrium during dolomitization of marine limestone in reaction with MgCl₂ solution at 150°C for 10 and 20 days. On the experiment using the pulverized limestone of 7.5 g and 25 ml of 2 M MgCl₂ solution, 90% of the calcite transformed into dolomite at 150°C within 20 days. The dolomitized products showed that there is no significant change of REE abundances of original marine limestone. This is experimental evidence for the field observation that dolostones sometimes preserve the REE and Y signatures of limestone precursors.