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This paper describes the suture zone between the Asian plate and the accreted Kohistan island arc in the Chitral district of NW Pakistan.The southern part of the Asian plate consists of two tectonic units separated by the N-dipping Reshun fault. The northwestern unit comprises Devonian carbonates and quartzites overlain by Devonian to Permian shales and slates with some limestones (Lun shales). Its structure is complex with S-verging thrusts and isoclinal folds. Along the Reshun fault, the relatively undeformed Reshun Formation may represent molasse. The central unit includes N-dipping Upper Palaeozoic slates and quartzites (Darkot Group), probably faulted against an antiformal tract of slates, schists derived from a volcanic assemblage and Cretaceous limestones (Chitral slate, Koghozi greenschist, Krinj and Gahiret limestones). Asian plate sediments are intruded by granitic and granodioritic plutons, variably deformed and locally porphyritic.The Northern suture melange of volcanic, sedimentary and serpentinite blocks in a slate matrix separates the Asian plate from the southeastern unit, the Kohistan arc. This comprises Cretaceous volcanic rocks with some sediments (Shamran Volcanic Group, Drosh, Purit and Gawuch Formations) intruded by aphyric diorites, tonalites and granites. These intermediate plutonic rocks pass southwards into a mafic layered complex and amphibolites representing deep levels of the arc. The volcanic rocks and sediments dip to the N and have a horizontal lineation. The structural history of southern Asia and Kohistan is consistent with an originally curved Northern suture: motion of the arc was initially to the NE relative to Asia and subsequently to the NW.

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A 1: 500 000 scale geological map covering large parts of the northwest Pakistan-southeast Afghanistan border region between 31–34° N and 69–71° E has been compiled. The map covers the tribal areas of Kurram and of North and South Waziristan in Pakistan, where the map is based on unpublished data of the Federally Administered Tribal Areas Development Corporation. The map area comprises Precambrian crystalline rocks of the Indian and Kabul blocks, Permian to Quaternary sedimentary rocks, and the Late Cretaceous-Palaeocene Kabul-Altimur and Zhob-Waziristan-Khost ophiolite complexes. The Himalayan collision resulted in extrusion of the Kabul Block along the Chaman Fault system and formation of the Katawaz Basin which was filled with clastic deposits of the ‘Early-Indus’ fan. Ongoing contractional tectonics led to southward thrusting of the Spinghar Indian crystalline basement over the Miocene Murree Formation. New names and type sections are proposed for six units in the Spinghar and South Waziristan. These units are the Daradar Dolomite, Spinghar Quartzite, Sikaram Series, Makai Limestone, Wana Schist and Kaniguram Slates.