| Author(s): | Iwatsuki, T., Satake, H., Metcalfe, R., Yoshida, H. and Hama, K. |
| Year: | 2002 |
| Title: | Isotopic and morphological features of fracture calcite from granitic rocks of the Tono area, Japan: a promising palaeohydrogeological tool |
| Reference: | Applied Geochemistry, 17, 1241-1257 |
| Keywords: | calcite, calcite morphology, oxygen isotopes, carbon isotope, stable isotope, groundwater, fracture mineralisation, palaeohydrogeology, granite, crystalline, Japan |
| Overview: | Fracture calcites have been studied in borehole cores in granite (up to 100 m depth) in the Tono area, central Japan. The objective was to assess the hydrochemical evolution of the presently low-salinity groundwater system. The petrography, morphology and isotopic composition of the calcite was characterised. Based on the earlier application of calcite morphology at Sellafield (UK), these authors found that the variation in calcite crystal forms imply a similar range of groundwater salinity to that inferred from the isotopic data. The calcite morphology variations may preserve a record of changing salinity of coexisting groundwaters. The authors consider that calcite morphological data, coupled with isotopic data, could provide a powerful palaeohydrogeological tool in this situation. |