Revised lithostratigraphy of the Pishin Belt, northwestern Pakistan
Keywords:
Lithostratigraphy; Pishin Belt; Tectono-stratigraphic Zones; Younger fluvial systemsAbstract
The Pishin Belt is divisible into six tectono-stratigraphic zones bounded by major thrusts and/or unconformities; each zone having its distinct lithostratigraphy. Muslim Bagh Ophiolite is the base and Zone-I of this belt. Zone-II comprises the Eocene Nisai Formation and Oligocene Khojak Formation. The newly proposed Miocene Dasht Murgha group comprises Zone-III, the Miocene-Pliocene Malthanai formation comprises Zone-IV, the Pleistocene Bostan Formation makes Zone-V, and the flat-laying Holocene deposits of the Zhob valley comprise Zone-VI. The role of tectonics on sedimentation and stratigraphy of the Pishin Belt is evident from composition of the Neogene succession, which contains clasts of Muslim Bagh Ophiolite, and Nisai and Khojak formations, reflecting uplift of the pre-Miocene succession that supplied detritus for the younger fluvial sediments of the Dasht Murgha group, Malthanai and Bostan formations. In general, the tectono-stratigraphic zones and their bounding thrusts within the Pishin Belt are progressively younger towards south and southeast. We propose that tectonic uplift and east-southeastward transport of hanging walls of the major thrusts caused subsidence of the footwalls, which provided accommodation for development of the younger fluvial systems in which the Dasht Murgha group, Malthanai formation, Bostan Formation and the flat-laying Holocene deposits of the Zhob valley were deposited respectively.
References
Ahmed, Z., 1996. Nd- and Sr-isotopic constraints and geochemistry of the Bela Ophiolite Melange complex, Pakistan. International Geology Review, 38, 304–319.
Allemann, F., 1979. Time of Emplacement of the Zhob Valley Ophiolites and Bela Ophiolites, Baluchistan (Preliminary Report). In: Farah,
A., DeJong, K.A. (Eds.), Geodynamics of Pakistan: Geological Survey of Pakistan, Quetta, 215-242.
Bender, F.K., Raza, H.A. (Eds.), 1995. Geology of Pakistan. Gebruder Borntreager, Germany.
Carter, A., Najman, Y., Bahroudi, A., Bown, P., Garzanti, E., Lawrence, R.D., 2010. Locating earliest records of orogenesis in western Himalaya: Evidence from Paleogene sediments in the Iranian Makran region and Pakistan Katawaz basin. Geology, 38, 807-810.
Cheema, M.R., Raza, S.M., Ahmad, H., 1977. Cenozoic. In: Shah, S. M. I. (Ed.), Stratigraphy of Pakistan: Geological Survey of Pakistan, Quetta, Memoirs, 12, 56-98.
Davies, L.M., 1930. The fossil fauna of the Samana Range and some neighbouring area, Part 1: An introductory note, India Geological Survey, Memoirs, Palaeontologica Indica, New Series; The Palaeocene Foraminiferaibida, 15, 13.
Gnos, E., Khan, M., Mahmood, K., Khan, A.S., Villa, I., 1996. Bela oceanic lithosphere assemblage and its relation to the reunion hotspot. Terra Nova, 10, 90-95.
Hunting Survey Corporation, 1960. Reconnaissance geology of part of West Pakistan. A Colombo Plan Co-operative project; Toronto.
Ingram, R.L., 1954. Terminology for the thickness of stratification and parting units in sedimentary rocks. Geological Society of America Bulletin, 65, 937-938.
Iqbal, M., 2004. Integration of Satellite Data and Field Observation in Pishin Basin, Balochistan. Pakistan Journal of Hydrocarbon Research, 14, 1-17.
Jadoon, I.A., Khurshid, A., 1996. Gravity and Tectonic model across the Sulaiman fold belt and the Chaman fault zone in western Pakistan and eastern Afghanistan. Tectonophysics, 254, 89-109.
Kazmi, A.H., Abbasi, I.A., 2008. Stratigraphy and Historical geology of Pakistan. Department and National Centre of Excellence in Geology, University of Peshawar, Pakistan.
Kazmi, A.H., Jan, M.Q., 1997. Geology and Tectonics of Pakistan. Graphic Publishers, Pakistan.
Khan, A.M., Srivastava, S.K. 2006. The paleogeographic significance of Aquilapollenites occurrences in Pakistan. Journal of Asian Earth Sciences, 28, 251–258.
Khan, M., Kerr, A.C., Mahmood, K., 2007a. Formation and tectonic evolution of the Cretaceous-Jurassic Muslim Bagh ophiolitic complex, Pakistan: Implications for the composite tectonic setting of ophiolites. Journal of Asian Earth Sciences, 31, 112-127.
Khan, S.D., Mahmood, K. Casey, J.F., 2007b. Mapping of Muslim Bagh ophiolite complex (Pakistan) using new remote sensing, and field data. Journal of Asian Earth Sciences, 30, 333-343.
Lawrence, R.D., Khan, S.H., DeJong, K.A., Farah, A., Yeats, R.S., 1981. Thrust and strike slip fault interaction along the Chaman transform zone, Pakistan. In: McClay, K., Price, N.J. (Eds.), Thrust and Nappe Tectonics. Geological Society of London, Special Publication, 9, 363-370.
Lawrence, R.D., Khan, S.H., Nakata, T., 1992. Chaman fault, Pakistan-Afghanistan: Annals Tectonicae, Special Issue, 6, 196-22.
Lawrence, R.D., Yeats, R.S., 1979. Geological Reconnaissance of Chaman Fault in Pakistan. In: Farah, A., DeJong, K.A., (Eds.), Geodynamics of Pakistan. Geological Survey of Pakistan, Quetta, 351-357.
Mahmood, K., Boudier, F., Gnos, E., Monie´, P., Nicolas, A., 1995. 40Ar/39Ar dating of the emplacement of the Muslim Bagh ophiolite, Pakistan. Tectonophysics, 250, 169–181.
Powell, C.M.A., 1979. A Speculative Tectonic History of Pakistan and Surroundings: Some Constraints from the Indian Ocean. In: Farah, A., DeJong, K. A. (Eds.), Geodynamics of Pakistan, Geological Survey of Pakistan, Quetta, 5-24
Qayyum, M., 1997. Sedimentation and Tectonics in the Tertiary Katawaz Basin, NW Pakistan: A Basin Analysis Approach. Unpublished Ph.D. thesis, Oregon State University, USA.
Qayyum, M., Lawrence, R.D., Niem, A.R., 1997a. Molasse-delta-flysch continuum of the Himalayan orogeny and closure of the Paleogene Katawaz remnant ocean, Pakistan. International Geology Review, 39, 861–875.
Qayyum, M., Lawrence, R.D., Niem, A.R., 1997b. Discovery of the palaeo-Indus delta-fan complex. Journal of the Geological Society, London, 154, 753–756.
Qayyum, M., Niem, A.R., Lawrence, R.D., 1994. Closure of the Neo-Tethys and evolution of newly discovered delta in Tertiary Katawaz basin, Pakistan. Geological Society of America Abstracts with Programs, 26 (7), A-242.
Qayyum, M., Niem, A.R., Lawrence, R.D., 1996. Newly discovered Paleogene deltaic sequence in Katawaz basin, Pakistan and its tectonic implications. Geology, 24, 835-838.
Qayyum, M., Niem, A.R., Lawrence, R.D., 2001. Detrital modes and provenance of the Paleogene Khojak Formation in Pakistan: Implications for early Himalayan orogeny and unroofing. Geological Society of America Bulletin, 113, 320-332.
Rossman, D.L., Ahmad Z., Rehman, H., 1971. Geology and economic potential for chromite in the Zhob valley ultramafic complex (Jang Tor Ghar) Hindubagh, Quetta Division, West Pakistan. Geological Survey of Pakistan and US Geological Survey Interim Report, PK-50, 63.
Sarwar, G., 1992. Tectonic setting of the Bela ophiolites, Southern Pakistan. Tectonophysics, 207, 359–381.
Sarwar, G., DeJong, K.A., 1979. Arcs, Oroclines, Syntaxes: the Curvatures of Mountain Belts in Pakistan. In: Farah, A., DeJong, K.A. (Eds.), Geodynamics of Pakistan, Geological Survey of Pakistan, Quetta, 341-349.
Searle, M.P., Corfield, R.I., Stephenson, B. McCarron, J., 1997. Structure of the North Indian continental margin in the LadakhZanskar Himalayas: implications for the timing of obduction of the Spontang ophiolite, IndiaAsia collision and deformation events in the Himalaya. Geological Magazine, 134, 297-316.
Siddiqui, R.H., Aziz, A., Mengal, J.M., Hoshino, K., Sawada, K., 1996. Geology, Petrochemistry and tectonic evolution of Muslim Bagh ophiolite complex, Pakistan. Proceedings of Geoscience Colloquium Geoscience Laboratory, Geological Survey of Pakistan 16, 11-46.
Treloar, P.J., Izatt, C. N., 1993. Tectonics of the Himalayan collision between the Indian Plate and the Afghan block: a synthesis. In: Treloar, P.J., Searle, M.P. (Eds.), Himalayan Tectonics. Geological Society, London, Special Publication, 74, 69-87.
Vredenburg, E., 1901. A geological sketch of the Balochistan desert and part of eastern Persia. India Geological Survey, Memoir, 31, 179-302.
Vredenburg, E., 1904. On the occurance of species of Halorites in the Trias of Balochistan. India Geological Survey Records, 31 (3), 162-166.
Vredenburg, E., 1909. Report on the geology of Sarawan, Jhalawan, Mekran and the state of Las Bela, considered principally from the point of view of economic development. India Geological Survey Records, 3, 189-215.
