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Using marble samples from the Nikani Ghar marble and Nowshera Formation from Northern Pakistan the determination of the temperature of metamorphism was undertaken with the help of calcite-dolomite solvus geothermometer. Two types of marbles, that is, calcite-dolomite marble and quartz-bearing calcite-dolomite marble were selected. Petrographic and scanning electron microscope analysis of dolomite samples indicated different grain sizes. X-ray diffraction technique indicated the calcites Mg CO_3 content up to 7.93 mol.%. Nikani Ghar marble samples have shown lower contents of Mg CO_3 as compared to samples from Nowshera Formation. The calcite-dolomite-quartz marble has also showed relatively lower Mg CO_3 content and hence rather low temperature(~500 oC). The temperature reached during peak metamorphism of the investigated marble occurrence, based on calcitedolomite solvus was 628 oC. Metamorphic temperatures derived from the present study were shown as a linear graph and values were in good agreement with the published literature.
Using marble samples from the Nikani Ghar marble and Nowshera Formation from Northern Pakistan the determination of the temperature of metamorphism was undertaken with the help of calcite-dolomite solvus geothermometer. Two types of marbles, that is, calcite-dolomite marble and quartz-bearing calcite -dolomite marble were selected. Petrographic and scanning electron microscope analysis of dolomite samples showed different grain sizes. X-ray diffraction technique showed the calcites Mg CO_3 content up to 7.93 mol.%. Nikani Ghar marble samples have shown lower contents of Mg CO_3 as compared to samples from Nowshera Formation. The calcite-dolomite-quartz marble also also showed relatively lower Mg CO 3 content and hence rather low temperature (~ 500 oC). The temperature reached during peak metamorphism of the marble occurrence, based on calcited olomite solvus was 628 oC. Metamorphic temperatures derived from the present study showed shown a linear graph and values were in good agreement with the published literature.