Validity of sphalerite geobarometry and garnet- biotite geothermometry to estimate P-T conditions of metamorphism for the sediment-hosted base metal deposits in Besham area, northern Pakistan
Abstract
Regionally metamorphosed sediment-hosted stratiform exhalative type base metal deposits are exposed in the Lahor and Pazang properties of Besham area at the northern margin of the Indian plate. Sphalerite geobarometer and garnet-biotite geothermometer were used to calculate the P-T Conditions of metamorphism. These geothermobarometers yielded most convincing results for the studied deposits. These deposits and the host metasediments were subjected to amphibolite facies metamorphism with a metamorphic temperature of 585 ± 35 o C and a pressure of kb.8 ± 2kb.
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