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The Russian-Mongolian Expeditions and Research in Vertebrate Palaeontology

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The Russian-Mongolian Expeditions and Research in Vertebrate Palaeontology The Russian-Mongolian expeditions and research in vertebrate palaeontology I Introduction Cretaceous, Paleogene, and Neogene over a large part of southern Mongolia, and this promoted the preser- Central .lsia attracted the attention of palaeontolo- vation of fossils. Moderate tectonic activity has gener- gists after 'Tertiary mammals had been found in conti- ated small escarpments which reveal much of the nental sediments. At first, Kichthofen (1877) argued thickness of the sedimentary succession. 'The absence / that Central Asia had been flooded by a huge sea of Pleistocene ice sheets meant that the ancient which produced marine deposits, the so-called deposits were not erased. Thus, in Central Asia, there Khankha deposits. Rorisyak (1015) predicted that is a nearly continuous series of lake and river deposits Mongolia would be a storehouse of palaeontological containing continental biota, beginning in the Late treasures, based on his study of Tertiary mammals in Jurassic, and in some places in the Late 'l'riassic. 1 adjaceut Kazakhstan, and on the discovery of a bronto- The territory of Mongolia extends nearly 2400 km there tooth in 'I'ertiary rocks on the Plateau from east to west and nearly 1300 krri from north to 1 Khooldzin, south of Iren Dabasu Lake, Inner south. Most of Mongolia is a middle-level mountain Mongolia, China, by Vladi~nirObruchev in 1892 plateau with average heights 1000-1200 In above sea , (Ohruchev, 1893). Borisyak expected rich finds of level. In the southern half of the country, mountain lertiary mammals in Mongolia, since he considered ridges of the blongolian and Gobi Altai with heights I I that Central Asia was the centre of origin of Cenozoic fiom 1.500 to 4000 m above sea level, lie on either side mammals. These prognoses stimulatecl the Central of extended depressions, filled with Mesozoic and 1 Asiatic Expedition of the American Museum of Cenozoic deposits, the products of erosion of the sur- Natural History in the 1020s, and the environs of lren rounding high countries (Murzaev, 1948). In these Dabasu Lake were the first area investigated; here the depressions the main palaeontological riches of Expedition discovered a Cretaceous fauna of dino- Mongolia are buried. saurs and Paleogene and Neogene mammals (Granger and Rerkey, 1922). Abbreviations Why is blongolia so rich in remains of ancient ver- tebrates? During the past 200 Myr, since the early AR,%S,Archives of the Russian :\cademy of Sciences; hlesozoic, the territory of Mongolia was never .-2S USSR, :\cademy of Sciences of the USSR; t;, Fund covered by the sea. The arid continental climate of the of the ARAS; C.4i7, Central Asiatic Expedition of the past 30 blyr has not encouraged the formation of a American Museum of Natural History; L, List of the thick soil cover, nor the development of vegetation, ARAS; MAS, Mongolian Academy of Sciences; MPL, and has generated strong erosion bv water, wind, and Mongolian Palaeontological Expedition of the temperature change. Rapid sedimentation, associated :\cademy of Sciences of the USSR; MPR, htlongolian with significant water supplies and broken relief, I'eoples' Republic; P, Page of the .lR.%S; I'lN, occurred for significant periods of time in the Palaeontological lnstitute of the RAS; R..\S, Russian 1: A-. KUKOCHKIN & R. R.IKSHO12L) Academy of Sciences; RMPE, Joint Kussian- led by B.S. Dombrovski from the Far-Eastern Mongolian Palaeontological Expedition; SMPE,Joint University of Vladivostok conducted research in Soviet-Mongolian Palaeontological Expedition; U, Central and Eastern Mongolia. It did some work on Deposition Unit of the ARAS. the new large dinosaur sites (Dombrovski, 1926). Further expeditions of Soviet scientists conducted researches in Mongolia from 1920 to 1930. The geog- The first discoveries of Mesozoic and Cenozoic raphers and hotanists A.D. Simukov, E.M. Murzaev, vertebrate sites ,4.A. Yunatov, and B.M. Chudinov found Cretaceous From 1922 to 1930, the Central Asiatic Expedition of dinosaurs in the Southern Gobi. In the Eastern Gobi, the American Museum of Natural History (CAE), 20 sites of Paleogene mammals and Cretaceous dino- under the leadership of Roy Chapman Andrews, saurs were found by the geologists A.P. Chaikovskii, worked in Mongolia. They found Late Cretaceous A.N. Alekseichik, N.I. Delnov, and Yu.S. Zhelubovskii faunas of vertebrates (Protocerntops, small carnivorous (Marinov et nl., 1973), and later, some of these data dinosaurs, clutches of dinosaur eggs, mammals) at the were used by I. Efremov. Bayan Zag site in Southern Mongolia and Early Cretaceous dinosaurs (Psittncosnurus) and fishes in the Mongolian Palaeontological Expedition (MPE) Andai Khudag and 00sh sites in the Lakes Valley of of the Academy of Sciences of the USSR, Central Mongolia. The CAE also opened the 1946- 1949 Palaeocene Gashato site near Bayan Zag and the Oligocene Ardyn Ovoo (= Ergil Ovoo, = Ergiliin Zoo) At the end of 1940, the Scientific Committee of the site in south-eastern Mongolia and the Tatal Go1 site MPR sent a letter to the director of the PIN, 12. in the Lakes Valley, which produced many new Borisyak, inviting him to organise a palaeontological Paleogene mammals. Berkey and Morris (1 92 7a, b) expedition to Mongolia in 1941. The offer was agreed divided the Cretaceous deposits of Mongolia into 13 with the Praesidium of the AS USSR and by the formations, and they considered that Late Cretaceous Council of the Peoples' Commissars of the USSR, and climates were arid and semi-desert, though in the money was allocated for the expedition. Yu.A. Orlov Early Cretaceous epoch was more humid with many was nominated chief of the expedition, and I.A. lakes, a wide river network, and rich vegetation. Efremov vice-chief. Plans for the expedition included Practically simultaneously with the CAE, Soviet equipment for 10 people and an estimated duration of geologists began searching for minerals in Mongolia as 3.54 months of field work, covering Southern technical assistance to the young Mongolian Republic. Mongolia, the Trans-Altai and Middle Gobi, and The fill story of the geological exploration of Western Mongolia. Three GAS-AA motor trucks were Mongolia and adjacent regions of China by Russian received. However, because of a delay in the receipt of and Western scientists has been told by Marinov foreign passports for travel outside the USSR, the (1967). From this book, we will summarize the main expedition could not leave Moscow at the end of May, projects by Soviet scientists. as was planned, and it was postponed to 1942 (ARAS; From 1925 on 1932 geological expeditions of the E 1712; L. 1; U. 18; pp. 1-38.). Then, in June 1941, Academy of Sciences of the USSR to Mongolia were Germany attacked the USSR, and clearly the work of led by 1.P. Rachkovskii. These expeditions investigated the MPE had to be postponed. rich Tertiary vertebrate sites in Western and Eastern As early as the end of 1945, Yu. Orlov submitted a Mongolia and Cretaceous dinosaur localities in request to run the Palaeontological expedition to Eastern Mongolia (Kupletskii, 1926; Lebedeva, 1926, Mongolia to the Praesidium of the AS USSR. This 1934; Rachkovskii, 1928; Rachkovskii and Lebedeva, petition was accepted by the Council of Ministers of 1932; Belyaeva, 1937). In 1925, a geological expedition the USSR (Resolution N 2051 PC of February 16, 'fhe Russian-Mongolian expeditions 1946) and on March 28, 1046, the Praesidium of the both in terms of finds of Paleogene mammals and Late AS USSR gave an order for the organization of the Cretaceous fossils. New large dinosaur sites were dis- MPE for a period of seven months (AR.iS; F. 171 2; I,. covered in the Southern and Eastern Gobi. 1; U. 73.; pp. 1 and 8). The expedition left bloscow at Particularly important were the finds in the Upper the beginning of .August, 1946. On :\ugust 10th it Cretaceous rocks of hadrosaurs and sauropods, as well reached Ulaanbaatar, and on September 1st began to as large terrestrial carnosaurs and ankylosaurs, gencr- work at Eayan Zag. The leader of the MPE was now ally unknown fiom the Old World, and at~undantfinds I.X. F:fremov, and Yu.A. Orlov \\,as its scientific adviser. of fossil trees, crocodiles, and fishes. These fossils all The preparators J.M. Eglon and M.1:. 1,ukiyanova also suggested to the Soviet geologists that in the Late worked in Mongolia on the first expedition, as did the Cretaceous Central .\sia was covered with extensive scientists K.K. Flerov, V.I. Cromov, and :\..I. lakes, bogs, and large rivers, opposite to the usr~alview Kirpichnikov. The 1946 MPE worked fbr 2.5 rnonths in that these territories had experienced arid conditions the field. In Dalanzadgad, a forwarding base with since the Mesozoic. stocks of petrol was created, from which for\mrding 'The u~lioleof 1947 was devoted to the preparation routes extended over the whole of Southern and of the seconcl expedition. main task of this expedi- Eastern Mongolia. The motor vehicles travelled a tion was excavation at Nemegt and Rayan Shiree with total of 4700 km. The expedition returned to large numbers of Lvorkers and large numbers of Ulaanbaatar on November 4th, and left fix hloscow by trucks. The trucks, equipment, and drivers were sent rail on January 7tI1, 1947. from Moscow to Ulaanl~aatarin Novclnher 1947, and The MPE in 1946 carried out reconnaissance and in December the expedition leaders arrived. The field prospecting on three main routes (Efremov, 1948, I~aseat 1)alanzadgacl was set up during the severe 1919; Orlov, 1952). North of Dalanzadgad, a northern blongolian winter with stocks of equipment and group of routes included surveys at Bayan Zag, and petrol, and one of the field teams began \vork in the the new 1,ate Cretaceous sites Ulaan 66sh and Ailpi Eastern Gobi in March, 1948.
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