Chemical variations in clinopyroxene and garnet from eclogites of the Vara Valley (Voltri Group, Italy)
Chemical variations in clinopyroxene and garnet from eclogites of the Vara Valley (Voltri Group, Italy) (in Fourth international eclogite conference, Lauro Morten (editor))
European Journal of Mineralogy (February 1995) 7 (1): 103-117
Co-existing clinopyroxene-garnet pairs from seven samples of eclogite from a single body outcropping in the Vara Valley, W Liguria, were examined by EPMA and XRD. Both minerals show marked heterogeneities implying a broad scatter of chemical composition, as well as variations in the oxidation state of the clinopyroxene. Such features strongly affect calculation of the distribution coefficient (K (sub D) ) making the application of any exchange thermometry based on this mineral pair inaccurate or even effectively useless.