The Late Miocene Maragheh Fauna, Northwest Iran
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Recent Advances in Paleobiological Research of the Late Miocene Maragheh Fauna, Northwest Iran Majid Mirzaie Ataabadi1, Raymond L. Bernor 2,3, Dimitris S. Kostopoulos4, Dominik Wolf 3, Zahra Orak5, Gholamreza Zare5, Hideo Nakaya6, Mahito Watabe7 and Mikael Fortelius1,8 1 Department of Geology, University of Helsinki, P.O. Box 64, FIN-00014, Finland 2 National Science Foundation, GEO:EAR Sedimentary Geology and Paleobiology Program 3 College of Medicine, Department of Anatomy, Laboratory of Evolutionary Biology, Howard University, 520 W St. N.W., Washington D.C. 20059, USA 4University of Thessaloniki, Geological Department, Museum of Geology and Paleontology, 54124 Thessaloniki, Greece 5Department of Environment, MMTT, Tehran, Iran 6Department of Earth and Environmental Sciences, Faculty of Science, Kagoshima University, Japan 7 Hayashibara Museum of Natural Sciences, Okayama, Japan 8 Institute of Biotechnology, P.O. Box 56, FIN-00014 University of Helsinki, Finland I. Historical Background The fossil localities of Maragheh are located in the latter half of the 19th century (Abich 1858, the eastern Azarbaijan province, northwest Iran Brandt 1870, Grewingk 1881). These early at 37° 21' 08'' N latitude and 46° 24' 40'' E works provided data on Maragheh’s similarity longitude. The Maragheh fauna has long been to Pikermi. The Austrian paleontologist Pohlig considered one of the three most preeminent was invited by a merchant from the nearby city western Eurasian late Miocene Pikermian of Tabriz to visit the locality in 1884 and it was faunas, along with Samos and Pikermi in Pohlig that made the first comprehensive Greece. As with Pikermi and Samos, collection and geological study of Maragheh Maragheh is a true “Lagerstätte” because of (Pohlig, 1886). Pohlig explored extensively the shear abundance and diversity of its fauna. across the Maragheh basin and would appear It is unique amongst the three classical to have sampled fossils from nearly all, if not Pikermian faunas in its clear stratigraphic all of the Maragheh section. The Pohlig display and layer-cake stratigraphy with collection in the Naturhistorisches Museum, several, laterally continuous volcanic ashes Wien is extraordinary as an early collection that are readily amenable to radioisotopic because much of it preserves locality dating. information which facilitates understanding of A Russian explorer, Khanikoff has been its stratigraphic provenance. Two other credited with first finding the Maragheh site in Austrian paleontologists, Rodler and Kittl, 1840 and sending a small collection to Dorpat visited Maragheh and made an extensive University (now University of Tartu, Estonia). collection of fossils which were later published The Maragheh fauna was initially studied in by Kittl (1887), Rodler (1890), Rodler and MIRZAIE ATAABADI ET AL. / RECENT ADVANCES IN MARAGHEH RESEARCH Weithofer (1890) and Schlesinger (1917). There are three important outcomes Damon, from the British Museum of Natural from the field work undertaken in the 1970’s History, London made a small collection including: a) collection of fossils with close briefly communicated by Lydekker in 1886. In regard to stratigraphic provenance which has 1897, the French paleontologist Marcellin led to a biostratigraphy of the Maragheh fauna, Boule secured permission to conduct a b) study of all collections to better understand paleontological expedition to Maragheh in the taxonomy and diversity of the mammalian 1904. The 1904 French expedition to fauna, and c) application of a variety of Maragheh was organized at a very grand scale geochronologic tools to secure well resolved for this time in paleontology. A group of ages for the Maragheh section and its faunas. French paleontologists assisted by 12 local After 30 years cessation of excavation laborers excavated a large sample of Maragheh activities in the Maragheh basin, Iran’s fossils from Kingir, Kopran, Shollevend and Department of Environment (DOE) and Kermedjawa (Mecquenem 1905, 1906, 1908, National Museum of Natural History (MMTT) 1911, 1924-25). started a new initiative and sponsored new More than 50 years elapsed before other excavations in the area which resulted in reported expeditions occurred at Maragheh. nomination of 10 km2 of Maragheh Takai of Tokyo University collected Maragheh fossiliferous area as a national protected zone fossils from Kerjabad (Takai 1958). Robert and establishment of a field museum and Savage of Bristol University also visited research station in the Dare Gorg (Gort Daresi) Maragheh in 1958 and collected fossils. area. The MMTT-University of Helsinki Tobien from the Johannes-Gutenberg initiative known as the International Sahand University, Mainz made important excavations Paleobiology Expedition (INSPE) has also of the middle portion of the Maragheh been recently started and is currently in sequence in the 1960’s (Tobien, 1968). During progress. This program has undertaken three the 1970’s three scientific groups conducted field seasons between 2007 and 2009, research at Maragheh: a combined Dutch- discovering several new localities and German group led by Erdbrink (Erdbrink et al. numerous fossils. The program has further 1976, Erdbrink 1976 (a,b), 1977, 1978, 1982, reinitiated study of the mammalian fauna with 1988), a joint University of Kyoto-Geological the intention of bringing them into a Survey of Iran led by Kamei (Kamei et al. contemporary taxonomic context for 1977, Watabe 1990, Watabe and Nakaya comparative paleoecological and 1991a,b) and the Lake Rezaiyeh Expedition paleobiogeographic studies. (LRE) led by Campbell (Campbell et al. 1980). Bernor was a student charged with the study of Abbreviations vertebrate fauna for the LRE which resulted in his PhD (1978) and manuscripts on the fauna, INSPE - International Sahand Paleobiology biostratigraphy and zoogeographic Expedition relationships of the fauna (1986) and the MMTT - Muze Meli Tarikh Tabiei (National systematic, biostratigraphy and zoogeography Museum of Natural History), Tehran of the hipparionine horses (1985). An MNHN - Muséum National d’Histoire extensive review of the fauna with systematic, Naturelle, Paris chronologic and biogeographic comparisons to M2 – Upper second molar Pikermi and Samos was published by Bernor et NMW - Naturhistorisches Museum Wien al. (1996). UCR - University of California, Riverside 2 MIRZAIE ATAABADI ET AL. / RECENT ADVANCES IN MARAGHEH RESEARCH II. Geology and Stratigraphy (Urmiyeh-Dokhtar) volcanic belt in the northeast and the Sanandaj-Sirjan metamorphic The Maragheh basin is bounded to the north by belt (Mendelassar transform) in the southwest the NW-SE trending Anatolian transform fault, (Fig.1). The Urmiyeh-Bazman volcanic belt also known as the Tabriz fault, on the west by with its northwest-southeast trend is believed the N-S trending Urmiyeh fault and on the to have resulted from the collision of the south by the NW-SE Mendelasar transform Arabian and Iranian plates. The Sanandaj- fault. Regionally the Maragheh Basin and its Sirjan metamorphic belt with a similar trend associated transform faults are dominated by lies between the main Zagros thrust (crush the Zagros crush zone to the south and west. zone) and the Urmiyeh-Bazman belt Also, there are the Urmiyeh-Bazman (Davoudzadeh et al. 1997). Figure 1 – Geographic position and relationships of the Maragheh area to the major tectonic features (after Dewey et al. 1973 and Huber 1976) in N. W. Iran. During the Paleogene, northwest Iran Miocene, the last Tethyan seaway incursion experienced a wide range of post collisional regressed from this area ending the local arc volcanic activities. After this magmatism carbonate deposition cycle (Aghanabati 2004). event, clastic, evaporate, and carbonate Consequently, at the beginning of the sediments were deposited during the late Neogene, this domain emerged above sea level Paleogene and early Neogene (Lower Red and and developed as incipient mountain ranges, Qom Formations). By the end of the early basin troughs, and a topography resembling 3 MIRZAIE ATAABADI ET AL. / RECENT ADVANCES IN MARAGHEH RESEARCH present conditions (Davoudzadeh et al. 1997). soils. These uppermost horizons are more than The most significant deposits of this time are 350 m thick south of Sahand, but can be as terrestrial sediments and evaporites known much as 1000 m in thickness in areas near the collectively as the Upper Red Formation. The Anatolian transform (Bernor et al. 1980). remains of these deposits are not found in the Maragheh area but mostly occur north of the The Maragheh Group Tabriz Fault and south of Urmiyeh fault We describe herein the sedimentary horizons (Fig.1). It seems that these major faults in the of the Maragheh Group as they are expressed area, which have been active since the in the Maragheh Basin. Paleozoic (Aghanabati 2004), structurally The Basal Tuff Fm. represents a single controlled and prevented deposition of these air-fall unit of rhyolite tuff with local thickness units in the Maragheh Basin. Volcanic activity of over 80 m. This unit is a uniform, unbedded, was reinitiated in the late Miocene to middle structureless deposit of white, devitrified ash Pliocene interval in the Maragheh Basin and with randomly oriented crystals of mica and adjacent areas (Moin-Vaziri and Amin- fresh fragments of feldspar and quartz. The Sobhani 1977). unit represents a tremendous pyroclastic event The Late Miocene Maragheh with substantial outcrops south and northeast stratigraphic sequence accumulated on the of the central fossiliferous