Complex replacement of saddle dolomite by fluorite within zebra dolomites

A lateral transition of saddle dolomite into fluorite is observed within zebra dolomites of the Triassic Wetterstein Formation of the Drau Range (Carinthia/Austria). This lithological change is the result of a replacement of saddle dolomite by fluorite. Artificial staining of fluorite crystals by electron bombardment during cathodoluminescence indicates that fluorite crystals have a zonation typical of fluorite as well as of saddle dolomite. A combined dissolution/precipitation model is therefore proposed. Fluid inclusion studies indicate that these processes occurred at temperatures between 124 and 156 °C.