Geology of the Indus Suture Zone in the Mingora-Shangla Area of swat, N. Pakistan
Abstract
In the Mingora area the Indus suture zone is largely composed of metamorphosed ophiolites and melanges which have been wedged in between the Indo-Pakistan crustal plate and the Kohistan andesitic arc block. The Indo-Pakistan subcontinental sequence is made up of the twice metamorphosed Munglaur crystalline schists, the intrusive Swat granite gneiss, and the unconformably overlying once metamorphosed Alpurai and Saidu schists. The recognition of this unconformity requires major revision of the stratigraphic correlation of these units which were previously all considered to be Precambrian. Those above the unconformity are probably Phanerozoic, and the Saidu schist may be the local a metamorphosed equivalent of the Indus flysch of Ladakh. The ophiolitic and related rocks of the Indus suture melange group are subdivided into three separate units. The Shangla blueschist melange is locally present in the north and represents n subduction complex developed adjacent to the Kohistan arc, The Charbagh greenschist melamge crops out in the centre of the group and could be of either mid-oceanic island or island arc origin. The Mingora ophiolitic melange is abduction complex. It is characterized by metamorphism to talc-dolomite schist and emerald mineralization.
References
Asrarullah. Ahmad. Z., and Abbas, S.G., 1979. Ophiolites in Pakistan: an introduction. In 'Geodynamics Pakistan' (A. Farah B K.A. DeJoag, eds.), surv, Pakistan, Quetta, 181-182.
Abbas, S.G- & Ahmad, Z., 1979. The Muslimbagh Ophiolites In 'Geodynamics of Pakistan' (A- Farah & KA. DeJong. eds.), Geol. Surv. Pakistan Quetta. 243-2q.
Bakr, M.A. & Jackson, R.O., 1964. Geological map of Pakistan (1:2,000,000). Geol. Surv. Pakistan. Quetta.
Bard, J.P., l983. Metamorphic evolution of an obducted island arc: Example of the Kohistan (Pakistan) in the Himalayan collided range. Geol. Bull. Univ. Peshawar 16, 105-184.
Bard, J.P., Jan. M.Q., Maluski H., Matte, B., & Proust, F., 1979. Position et extension de la "ceinture" metamorphique a facies schistes bleus dans I' Himalaya du Pakistan. Nod 7e R. Ann. Se. Tern. Lyon, 1-29.
Bard, J.P., Maluski. H., & Proust, F., 1980. The Karakoram sequence: crust and mantle oi an abducted island arc. Geol. Bull. Univ. Peshawar 13, 87-94.
Barrett. J.I., and Spooner, E.T.C., 1977. Ophiolitic breccia associated with allochthonous oceanic crustal rocks in the East Ligurian Appenines, Italy: a comparison with observations from rifted oceanic ridges. Earth Planet. Sci. letters 35, 79-91.
Calkins, J.A., Offield, T W., Abdullah, S.K.M., and Tayyab Ali. S., 1975. Geology of the southern Himalaya in Hazara, Pakistan, and adjacent areas. US. Geol. Surv. Prof. Paper 7115--C, 1-29.
Chaudhry, M.N., & Page, B.M., 1975. Recycled Franciscan material in Franciscan mélange west of Paso Robles, California. Geol. Soc. America Bull. 86, 1089-1095.
Chaudhry, M.N., Ashraf, M., Hussain, S.S., & IqbaI, M., 1976. Geology and petrology of Malakand and a part of Dir (Toposheet 38 N/14). Geol. Bull. Punjab Univ. 12, 17-40.
Cowan, D.S., 1978. Origin of blueschist-bearing chaotic rocks in the Franciscan complex, Sari Simeon, California. Geol. Soc. America Bull. 89, 145-1423.
Coward. M.P., Jan M.Q., Rex. D., Tarney, J., Thirlwall, M., & Windley, B.F., 1982. Geo-tectonic framework of the Himalayas of N. Pakistan. Jour. Geol. Soc. London 139, 299-308.
Davies, R.G., 1962. A green beryl (emerald) near Mingora, Swat state. Geol. Bull. Punjab Univ. 2, 51-52.
DeJong. K.A. & Subhani, A.M., 1979. Note on the Bela ophiolites with special reference to the Kanar area. In 'Geodynamics of Pakistan' (A. Farah & K.A. DeJong, eds.), Geol. Surv. Pakistan, Quetta, 263-270.
Desio, A., Premoli, I., & Ronchetti, C.R., 1977. On the Cretaceous outcrop in the Chumar Khan and Laspur Gilgit-Chitral, northwest Pakistan. Riv. Ital. Paleont. 83, 561-574.
Desio, A., & shams, F.A., 1980. The age of the blueshists and the Indus Kohistan suture line, Northwest Pakistan. Acad. Naz. Dei Lincei 8, 74-79.
Dewey, J.F., & Bird, J.M., 1971. Origin and replacement of the ophiolite suite: Appalachian ophiolites in Newfoundland. Jour. Geophys. Res. 76, 3179-3206.
Dewey, J.F., & Burke, C.A., 1973. Tibetan, Variscan, and Precambrian basement reactivation, products of continental collision. Jour. Geology 81, 683-692.
Frank, W., Gansser, A., and Trommsdorf, V., 1977. Geological observations in the Ladakh area (Himalaya), a preliminary report. Schweiz. Mineral. Petrog. M.H. 57, 89-113.
Gansser, A., 1974. The ophiolitic melange, a worldwide problem on Tethyan examples. Eclogae Geol. Helv. 67, 479-507.
Gansser, A., 1980. The significance of the Himalayan suture zone. Tectonophysics 62, 37-52.
Gansser, A., 1981. The geodynamic history of the Himalayas. In 'Zagros-Hindu Kush-Himalaya Geodynamic Evolution' (H. Gupta & F. Delany, eds.), American Geophys. Union Geodynamics Series 3, 111-121.
Guiraud, M., Leyreloup, A.F., and Proust, F., in press. Petrology of the glaucophane bearing rocks from Khost, Afghanistan, and from Kohistan, northern Pakistan.
Hsu, K.J., 1968. Principles of inelange and their bearing on the Franciscan-Knoxville paradox. Geol. Soc. America Bull. 79, 1063-1074.
Hsu, K.J., 1974. Melanges and their distinction from olistrostronles. In 'Modern and Ancient Geosynclinal Sedimentation' (R.1-I. Dott, Jr. & R.H. Shaver, eds.), Soc. Econ. Paleont. Min., Special Publ. 19, 321-333.
Jan, M.Q., 1968. Petrography of the emerald-bearing rocks of Mingora (Swat state) and Prang Char (Mohmand Agency), West Pakistan. Geol. Bull. Univ. Peshawar 3, 10-11,
Jan, M.Q., 1977. The Kohistan basic complex, a summary based on recent petrological research. Geol. Bull. Univ. Peshawar 9-10, 36-42.
Jan, M.Q., 1980. Petrology of the obducted mafic and ultramafic metamorphites from the southern part of the Kohistan island arc sequence. Geol. Bull. Univ. Peshawar 13, 95-107.
Jan, M.Q., & Tahirkheli, R.A.K., 1969. The geology of the laver part of Indus Kohistan, West Pakistan. Geol. Bull. Univ. Peshawar 4, 1-13.
Jan, M.Q., & Svmes, R.F., 1977. Piedmontite schist from upper Swat, NW Pakistan. Min. Mag. 41, 537-510.
Jan, M.Q., Kamal, M.Q., and Khan, M.I., 1981. Tectonic control over emerald mineralization in Swat. Geol. Bull. Univ. Peshawar 14, 101-109.
Kazmer, C., Hussain, S.S., & Lawrence, R.D., 1983. The Kohistan-Indian plate suture zone at Jawan Pass, Swat, Pakistan. Geol. Soc. America, Abst. with Programs, 15, 609.
Kazmi, A.H., and Rana, R.A., 1982. Tectonic map of Pakistan (1:2,000,000). Geol. Surv. Pakisran, Quetta, Pakistan.
Le Fort, P., Debon, F., & Sonet, J., 1980. The 'Lesser Himalayan' cordierite granite belt: Typology and age of the pluton of Mansehra, Pakistan. Geol. Bull. Univ. Peshawar 13, 51-61.
Lawrence. R.D., Kazmer, C., and Tahirkheli, R.A.K., 1983. The Main Mantle Thrust: a complex zone. Geol. Soc. America, Abst. with Programs, 15, 624.
Maluski. H. & Matte, P., 1984. Ages of alpine tectono-metamorphic events in the northwestern Himalaya (northern Pakistan) by 39Ar/40Ar method. Tectonics 3, 1-18.
Majid, M., and Paracha, F.A., 1980. Calc-alkaline magmatism at destructive plate margin in Kohistan, northern Pakistan. Geol. Bull. Univ. Peshawar 13, 109-120.
Martin, N.R., Siddiqui, S.F.A., & King, B.H., 1962. A geological reconnaissance of the region between lower Swat and Indus rivers of Pakistan. Geol. Bull. Punjab Univ. 2, 1-14.
Mattauer, M., Proust, F., & Tappolmier, Y., 1979. The Indian-Eurasian suture zone in northern Pakistan: Synthesis and interpretation of data at plate scale. In 'Geodynamics of Pakistan' (A. Farah & K.A. DeJong, eds.), Ged. Surv. Pakistan, Quetta, 125-130.
Molnar, P., & Tapponnier, P., 1975. Cenozoic tectonics of Asia: effects of a continental collision. Science 189, 419-426.
Ozkaya, I., 1982. Origin and tectonic setting of some melange units in Turkey. Jour. Geology 90, 269-278.
Powell, C. McA., 1979. A speculative tectonic history of Pakistan and surroundings: Some constraints from the Indian Ocean. In 'Geodynamics of Pakistan’ (A. Farah & K.A. DeJong, eds.), Geol. Sum. Pakistan, Quetta, 5-24.
Powell, C. McA., and Sr Conaghan, P.J., 1973. Plate tectonics and the Himalayas. Earth Planet. Sci. Letters 20, 1-12.
Shams, F.A., 1963. Reactions in and around a calcareous xenolith lying within the granite gneiss of Manglaur, Swat State. Geol. Bull. Punjab Univ. 3, 7-18.
Shams, F.A., 1972. Glaucophane-bearing rocks from near Topsin, Swat: First record from Pakistan. Pakistan Jour. Science 24, 343-345.
Shams, F.A., 1980. Origin of the Shangla blueschist, Swat Himalaya, Pakistan. Geol. Bull, Univ. Peshawar 13, 67-70.
Shams, F.A., and Jones, G.C., & Kempe, D.R.C., 1980. Blueschists from Topsin, Swat District, NW Pakistan. Min. Mag. 43, 941-943.
Stauffer, K.W., 1968. Silurian-Devonian reef complex near Nowshera, West Pakistan. Geol. Soc. America Bull. 79, 1331-1350.
Stocklin, I., 1977. Structural correlation of the Alpine ranges between Iran and Central Asia. Soc. Geol. France Mem. H. Ser. 8, 333-353.
Tahirkheli. R.A.K., 1979. Geology of Kohistan and adjoining Eurasian and Indo-Pakistan continents, Pakistan. Geol. Bull. Univ. Peshawar 11, 1-30.
Tahirkheli. R.A.K., 1980. Major tectonic scars of Peshawar vale and adjoining areas, and associated magmatism. Geol. Bull. Univ. Peshawar 13, 36-46.
Tapponnier. P., Mattauer, M., Proust, F., & Cassaigneau, C., 1981. Mesozoic ophiolites, sutures and large-scale tectonic movements in Afghanistan. Earth Planet. Sci. Letters 52, 35-71.
Tekeli, O., 1981. Subduction complex of pre-Jurassic age, northern Anatolia, Turkey. Geology 9, 68-72.
Thakur, V.C., 1981. Regional framework and geodynamic evolution of the Indus-Tsangpo suture zone in the Ladakh Himalayas. Trans. Royal Soc. Edinburgh 72, 89-97.
Thakur, V.C., & Bagati, T.N., 1983. Indus formation: an arc-trench gap sediment. In 'Geology of Indus suture zone of Ladakh' (V.C. Thakur & KX. Sharma, eds.), Wadia Inst. Of Himalayan Geology, Dehra Dun, 9-19.
Wadia, DN., 1975. Geology of India. TATA, McGraw-Hill, New Delhi, 1-508.
Yeats R.S. 8 Lawrence, R.D., 1983 (in press). Tectonics of the Himalayan Thrust Belt in northern Pakistan. Proceedings of United States-Pakistan Workshop on Marine Sciences in Pakistan: 11-6 Nov., 1982, Karachi, Pakistan.
Zeitler, P.K., 1983. Uplift and cooling history of the NW Himalaya, northern Pakistan: Evidence from fission-track and 39Ar/40Ar cooling ages. Unpubl. Ph.D. thesis, Dartmouth College, Hanover, N.H. 1-266.
