Geothermometry of calcite spar at 10-50 °C.

Carbonate geothermometry is a fundamental tool for quantitative assessment of the geothermal and geochemical evolution of diagenetic and hydrothermal systems, but it remains difficult to obtain accurate and precise formation temperatures of low-temperature calcite samples (below ~ 40 to 60 °C). Here, we apply three geothermometry methods (∆-thermometry, nucleation-assisted fluid inclusion microthermometry-hereafter NA-FIM-and oxygen isotope thermometry) to slow-growing subaqueous calcite spar samples to cross-validate these methods down to 10 °C. Temperatures derived by NA-FIM and Δ-thermometry agree within the 95% confidence interval, except for one sample.

Combined use of conventional and clumped carbonate stable isotopes to identify hydrothermal isotopic alteration in cave walls.

Alteration of conventional carbonate stable isotopes (δO, δC) in cave walls has been shown to be a useful tool to identify cave formation driven by deep-seated processes, i.e., hypogene karstification.