Petrology, mineralogy and textural relations of metaperidotites from the Serow area, NW Iran

Abstract

The studied area is located in the west Azerbaijan Province at north-west of Serow town. Variety of metamorphic rocks including metabasites, marbles and metaperidotites crop out in the area. The metabasites are metamorphosed under greenschist to amphibolite facies. The metamorphosed calcareous rocks are mainly marble in which calcite form more than 90% volume of the rocks. The metaperidotites are serpentinized. Degree of serpentinisation is different from low to high. The protolith composition of the metapridotites is determined as harzburgite and lherzolite on the basis of petrography, mineralogy, textural relations and geochemical data. Considering sequence of the metamorphic reactions and thermometry studies in the metaperidotites, the highest temperature for formation of tremolite and serpentine in these rocks are ~780 ºC and ~480 ºC respectively. Using the whole rock chemistry and chemical diagrams, the Serow serpentinized metaperidotites are located in the metamorphic peridotites field. On the basis of textural relations and geochemical data, the oceanic crust and ophiolite-related origin of the investigated serpentinized metaperidotites are more likely.

Keywords


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