Titanium Content of a Chloritoid-Quartz-Ilmenite Band in Ophiolitic Mel-Ange Near Prang Ghar, NW Pakistan
Abstract
Titanium is a valuable engineering metal and has many uses. In the greenstone of the Indus suture melange near Prang Ghar, a 200 m long and 1 to 3.5 m thick band consists essentially of chloritoid (31 to 59 vol. %), quartz (10 to 27 %), and ilmenite + Fe-oxide (8 to 25%). The rocks contain very high A12O3, total Fe2O3 and TiO2, and low SiO2, CaO, MgO and alkalis. The unusual composition may have formed from basaltic precursors of the greenstone by weathering (laterization) or alteration, followed by greenschist facies metamorphism. Chemical analyses of three samples, containing 5 to 10 wt. % TiO2, warrent further investigation of the area.
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