Tectonic Reinterpretation Constraints of the Western Most Kohistan Complex in Timargara, Dir District, Pakistan
Abstract
No detailed tectonic and structural studies were carried out in the western most extremity of the Kohistan area. People have been concentrating mostly along Indus canyon and Swat valley for geotectonic, structural, petrological and geochronological studies. Present investigation is the first study to thoroughly work out tectonic reinterpretation constraints of the western most Kohistan complex particularly in Timargara quadrangle and adjoining area of Warai consisting of 673 sq.km. The concept of under plating for the emplacement of major plutonic complexes is advocated in this. area as well, as was also found out in Swat and Indus canyons, i.e., the Balambat norite and Timargara gabbronorite which are different from Chilas complex magma type underplated the Dir tholeiitic amphibolites. These plutonic rock types are more evolved than those of main Chilas complex. The latter underplated Dassu meta-plutonic complex of Kamila amphibolites.
The Kamila amphibolites are further subdivided into Kamila group meta-plutonic calc-alkaline amphibolites and Dir metavolcanic tholeiitic amphibolites or precisely as Kamila amphibolites and Dir amphibolites which are advocated to be adopted due to their different provenances.
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