Isotopic Thermometry

A computer simulation approach to modelling the structure, thermodynamics and oxygen isotope equilibria of silicates

“…This is the basis for its use in thermometry. The energy changes in isotopic exchange reactions are of the order of a few joules per mole and thus too small to be measured calorimetrically (Clayton 1981). Direct measurement by exchange reactions is difficult, particularly at low temperatures, because the driving force for the reaction is small.…”

Oxygen isotope fractionation factors involving cassiterite (SnO2): I. calculation of reduced partition function ratios from heat capacity and X-ray resonant studies

“…There are several possible approaches to obtain data on equilibrium isotope constants of minerals (Clayton, 1981;Chacko, 1993;Chacko et al, 2001):…”

An experimental and theoretical determination of oxygen isotope fractionation in the system magnetite-H2O from 300 to 800°C

“…In our study, we employed either NaCl or HAc to promote magnetite recrystallization from either precursor magnetite or Fe metal, or transformation from hematite. However, an ideal isotopic exchange experiment is one controlled exclusively by diffusion (Clayton, 1981;O'Neil, 1986). Diffusion probably contributed significantly to exchange in the hightemperature experiments using magnetite as a starting material, particularly for those grains that were unaffected by grain growth.…”