Sajkowski L, Kamiya A, Mountain BW. 2022. An experimental study on the potential of Rhenium and Indium as geothermal tracers. Lower Hutt (NZ): GNS Science. 33 p. (GNS Science report; 2022/23). doi:10.21420/HNET-JY77.
Abstract
The experiment described in this report tested indium (In) and rhenium (Re) as potential geothermal tracers up to super-hot and supercritical conditions. The results show that Re is potentially a suitable candidate, however, In is not. The flow-through experiments were conducted in the temperature range of 200–400°C, and in presence of a NZ greywacke rock substrate. The results indicate that Re behaves conservatively, in presence of the rock and H2S. But supercritical conditions however, the low density of the fluid results in the loss of Re, making it unsuitable as a tracer under these conditions. The experiment shows that In cannot be used as a geothermal tracer as it appears to react with H2S even at room temperature. As part of this study, a sensitive ICP–MS procedure combined with a resin extraction method has been developed for measurement of In and Re in saline geothermal fluids. (The authors)
