Document Type : Original Research Paper


1 Ph.D. Student, Department of Geology, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran

2 Professor, Department of Geology, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran

3 Associate Professor, Department of Geology, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran

4 Associate Professor, Research Institute for Earth Sciences, Geological Survey of Iran, Tehran, Iran


The Miocene sediments in Neyriz region crop out  in Zagros Crushed Zone, between Zagros Main Fault and Zagros Ophiolite Zone. For paleoenvironmental studies of these sediments, two stratigraphic sections (Kuh-e Asaki and Horgan sections) have been measured and sampled. The thicknesses of these two sections are 424 and 440 m respectively and contain red and green sandstone, conglomerate and marl which are bounded unconformably between the Jahrum Formation and Bakhtiari conglomerate. Based on the field and petrographic studies, 14 sedimentary facies related to proximal, mid fan-delta; transition zone, delta slope and prodelta have been recognized for the Miocene succession. Due to the slope facies formed by the turbidity currents, grain fall and debris flows, the coarse grained clasts and poorly sorted texture, a fan-delta model is suggested for the succession. Also, the development of the slope facies indicates a paleo-slope and slope-type, deep-water fan-delta. The frequent intra-formational disconformities, irregular changes in grain size and present of gravity flows indicate an active tectonic sedimentary basin and reflux of coarse grained sediments (catastrophic events) to the proximal parts of Zagros Basin.


Alavi, M., 2004- Regional stratigraphy of the Zagros Fold-Thrust Belt of Iran and its proforeland evolution. American Journal of Science  304: 1-20.
Allen, J., 1963- The classification of cross-stratified units, with notes on their origin. Sedimentology  2: 93-114.
Allen, J., 1982- Mud drapes in sand-wave deposits: a physical model with application to the Folkescone Beds (early Cretaceous, southeast England). Proceedings of the Royal Society of London A  306: 291-345.
Allen, J., 1983- Studies in fluviatile sedimentation: bars, bar complexes and sandstone sheets (low-sinuosity braided streams) in the Brownstones (L. Devonian), Welsh Borders. Sedimentary Geology  33: 237-293.
Babaei, A., Babaei, H. A. and Arvin, M., 2005- Tectonic evolution of the Neyriz ophiolite, Iran; An accretionary prism model. Ofioliti  30: 65-74.
Benton, M. and Harper, D., 1997- Basic Palaeontology, Longman. Harlow  342 pp.
Berberian, M. and King, G. C. P., 1981- Towards a paleogeography and tectonic evolution of Iran. Canadian Journal of Earth Sciences  18: 210-265.

Beydoun, Z. R., Hughes Clarke, M. W. and Stoneley, R., 1992- Petroleum in the Zagros basin: a late Tertiary foreland basin overprinted onto the outer edge of a vast hydrocarbon-rich Paleozoic–Mesozoic passive margin shelf. In: Macqueen, R.W. & Leckie, D.A. (Eds.), Foreland Basins and Foldbelts. American Association of Petroleum Geologists Memoir  55: 309-339.

Colella, A., DeBoer, P. L. and Nio, S. D., 1987- Sedimentology of a marine intermontane Pleistocene Gilbert-type fan-delta complex in the Crati Basin, southern Italy. Sedimentology  34: 731-736.
Collinson, J., 1968- Deltaic sedimentation units in the Upper Carboniferous of northern England. Sedimentology  10: 233-254.
Collinson, J., 1969- The sedimentology of the Grindslow Shales and the Kinderscout Grit: a deltaic complex in the Namurian of northern England. Journal of Sedimentary Petrology  39: 194-221.
Conaghan, P. J. and Jones, J. G., 1975- The Hawkesbury Sandstone and the Brahmaputra: A depositional model for continental sandstones. Journal of Geological Society of Australia  22: 275-283.
Dickson, J., 1966- Carbonate identification and genesis as revealed by staining. Journal of Sedimentary Petrology  36: 491-505.
Fakhari, M. D., Axen, G. J., Horton, B. K., Hassanzadeh, J. and Amini, A., 2008- Revised age of proximal deposits in the Zagros foreland basin and implications for Cenozoic evolution of the High Zagros. Tectonophysics  451: 170-185.
Falcon, N., 1974- Southern Iran: Zagros mountains, Geological Society of London, Special Publication, 4: 199-211.
Feng, D., Deng, H., Zhou, Z., Gao, X. and Cui, L., 2015- Paleotopographic controls on facies development in various types of braid-delta depositional systems in lacustrine basins in China. Geosience Frontiers  6: 579-591.
Folk, R. L., 1980- Petrology of Sedimentary Rocks. Austin, Texas: Hemphill Press  182 pp.
Gobo, K., Ghinassi, M. and Nemec, W., 2014- Reciprocal changes in foreset to bottomset facies in A Gilbert-Type Delta: response to short-term changes in base level. Journal of Sedimentary Research  84: 1079-1095.
Hessami, K., Koyi, H. A., Talbot, C. J., Tabasi, H. and Shabanian, E., 2001- Progressive unconformities within an evolving foreland fold-thrust belt, Zagros Mountains. Journal of Geological Society, London  158: 969-981.
Hubert, J. F. and Hyde, M. G., 1983- Sheet flow deposits of graded beds and mudstones on an alluvial sandflat-playa system: Upper Triassic Blomidon redbeds, St Mary's Bay, Nova Scotia. Sedimentology  29: 457-474.
James, G. A. and Wynd, J. C., 1965- Stratigraphic nomenclature of Iranian oil consortium agreement area. American Association of Petroleum Geologists Bulletin  49: 94-156.
Koop, W. J. and Stoneley, R., 1982- Subsidence history of the Middle East Zagros basin, Permian to Recent. In: Kent, M.B.P. (Eds.), Philosophical Transactions of the Royal Society of London, Part A  305: 149-168.
Liu, T., Zhang, J. and Li, C. L., 2014- Sedimentary facies of prograded-type fan delta Hungjue area, Gaoyou Sag, China. Petroleum Science and Technology  32: 217-224.
Lowe, D., 1982- Sediment gravity flows; II, Depositional models with special reference to the deposits of high-density turbidity currents. Journal of Sedimentary Petrology  52: 279-297.
McCabe, P., 1977- Deep distributary channels and giant bedforms in the Upper Carboniferous of the Central Pennines, northern England. Sedimentology  24: 271-290.
McKee, E. D., Crosby, E. J. and Berryhill, H. L. Jr., 1967- Flood deposits, Gijou Creek, Colorado. Journal of Sedimentary Petrology  37: 829-851.
Miall, A., 1985- Architectural-element analysis: a new method of facies analysis applied to fluvial deposits. Earth Science Review  22: 261-308.
Miall, A., 1988- Reservoir heterogeneities in fluvial sandstones: Lessons from outcrop studies, Bulletin. American Association of Petroleum Geologists  72: 682-697.
Miall, A., 1996- The Geology of Fluvial Deposits. Sedimentary Facies, Basin Analysis, and Petroleum Geology, Berlin: Springer-Verlag  582 pp.
Nadimi, A., 2002- Mantle flow patterns ant the Neyriz paleo-spreading center, Iran. Earth and Planetary Science Letters  200: 93-104.
Navabpour, P., Angelier, J. and Barrier, E., 2007- Cenozoic post-collisional brittle tectonic history and stress reorientation in the High Zagros Belt (Iran, Fars Province). Tectonophysics  432: 101-131.
Nemec, W. and Postma, G., 1993- Quaternary alluvial fans in southwestern Crete: sedimentation processes and geomorphic evolution. In: Marzo, M. and Puigdefabregas, C. (Eds.), Alluvial Sedimentation International Association of Sedimentology. Special Publication  17: 235-276.
Nemec, W. and Steel, R. J., 1984- Alluvial and coastal conglomerates: Their significant features and some comments on gravelly massflow deposits. In: Koster, E. H. and Steel, R.j. (Eds.), Sedimentology of Gravels and Conglomerates. Memorial Canadian Society of Petrolium Geology  1-31.
Nemec, W., Steel, R. J., Gjelberg, J., Collinson, J. D., Prestholm, E. and Oxnevad, I. E., 1988- Anatomy of collapsed and re-established delta front in Lower Cretaceous of eastern Spitsbergen: gravitational sliding and sedimention processes. American Assosiation of Petroleum Geologist Bulletin  72: 545-476.
Nichols, G., 2009- Sedimentology and Stratigraphy. Wiley-Blackwell  432 pp.
Petrolink, G., 1998- Exploration and production features United Arab Emirates and Iran. Geo Arabia  3: 427–455.
Pirouz, M., Simpson, G. and Chiaradia, M., 2015- Constraint on foreland basin migration in the Zagros mountain belt using Sr isotope stratigraphy. Basin Research  27: 714-728.
Postma, G., 1990- Depositional architeture and facies of river and fan deltas: a synthesis. International Association of Sedimentologists, Special publication  10: 13-27.
Prior, D. B. and Bornhold, B. D., 1990- The underwater development of Holocene fan deltas. In: Colella, A. (Eds.), Coarse-grained Deltas. International Association of Sedimentologists, Spacial Publication 75-90.
Prothero, D. R. and Schwab, F., 1996- Sedimentary Geology, Freeman and Company, First edition 575 pp.
Reading, H., 1996- Sedimentary Environments: Processes, Facies and Stratigraphy. Oxford: Wiley-Blackwell 704 pp.
Ricou, L. E., 1971- Le croissant ophiolitique pe´ri-arabe une ceinture de nappes mise en place au cre´tace´ supe´rieur. Revue de ge´ographie physique et ge´ologie dynamique 13: 327-350.
Sarkarinejad, K., 2005- Structures and microstructures related to steady-state mantle flow in the Neyriz ophiolite, Iran. Journal of Asian Earth Sciences 25: 859-881.
Sherkati, S. and Letouzey, J., 2004- Variation of structural style and basin evolution in the Izeh Zone and Dezful Embayment, Central Zagros, Iran. GeoArabia  9: 131.
Stear, W., 1985- Comparison of the bedform distribution and dynamics of modern and ancient sandy ephemeral flood deposits in the southwestern Karoo region, South Africa. Sedimentary Geology 45: 209-230.
Steel, R. J. and Aasheim, S. M., 1978- Alluvial sand deposition in a rapidly subsiding basin (Devonian, Norway). In: Miall, A.D. (Eds.), Fluvial Sedimentology. Memorial Canadian Society of Petroleum Geologists 5: 385-412.
Stocklin, J., 1968- Structural history and tectonics of Iran. A review. American Association of Petroleum Geologists Bulletin  52: 1229-1258.
Tunbridge, I., 1981- Sandy high-energy flood sediments- some criteria fot their tecognition, with an example from the Devonian of S.W England. Sedimentary Geology 28: 79-95.
Tunbridge, I., 1984- Facies model for a sandy ephemeral stream and clay playa complex; the Middle Devonian Trentishoe Fotmation of North Devon, U. K. Sedimentology  31: 697-715.
Wescott, W. A. and Ethridge, E. G., 1990- Fan deltas; alluvial fans in coastal settings. In: Rachocki, A.H. & Church, M. (Eds.), Alluvial Fans: a Field Approach. London: Blackie  195-211.