ISSN 08695938, Stratigraphy and Geological Correlation, 2015, Vol. 23, No. 3, pp. 281–299. © Pleiades Publishing, Ltd., 2015. Original Russian Text © E.B. Volynets, 2015, published in Stratigrafiya. Geologicheskaya Korrelyatsiya, 2015, Vol. 23, No. 3, pp. 50–68. Cretaceous Deposits and Flora of the MuravyovAmurskii Peninsula (Amur Bay, Sea of Japan) E. B. Volynets Institute of Biology and Soil Science, Far East Branch, Russian Academy of Sciences, pr. 100letiya Vladivostoka 159, Vladivostok, 690022 Russia email: [email protected] Received August 21, 2013; in final form, March 24, 2014 Abstract—The Cretaceous sections and plant macrofossils are investigated in detail near Vladivostok on the MuravyovAmurskii Peninsula of southern Primorye. It is established that the Ussuri and Lipovtsy forma tions in the reference section of the Markovskii Peninsula rest with unconformity upon Upper Triassic strata. The continuous Cretaceous succession is revealed in the Peschanka River area of the northern Muravyov Amurskii Peninsula, where plant remains were first sampled from the lower and upper parts of the Korkino Group, which are determined to be the late Albian–late Cenmanian in age. The taxonomic composition of floral assemblages from the Ussuri, Lipovtsy, and Galenki formations is widened owing to additional finds of plant remains. The Korkino Group received floral characteristics for the first time. The Cretaceous flora of the peninsula is represented by 126 taxa. It is established that ferns and conifers are dominant elements of the Ussuri floral assemblage, while the Lipovtsy Assemblage is dominated by ferns, conifers, and cycadphytes. In addition, the latter assemblage is characterized by the highest taxonomic diversity. The Galenki Assemblage is marked by the first appearance of rare flowering plants against the background of dominant ferns and coni fers. The Korkino floral assemblage is subdivided into two subassemblages dominated by different groups: conifers in the early and flowering plants in the late. Keywords: Cretaceous deposits, floral assemblage, flora, MuravyovAmurskii Peninsula, Vladivostok DOI: 10.1134/S0869593815020070 INTRODUCTION collection are described in (Kryshtofovich, 1932; Kry shtofovich and Prynada, 1932, 1934). Vladivostok and its outskirts are located on the It should be noted that the age of these plant MuravyovAmurskii Peninsula. F.B. Schmidt, who remains was determined in a wide range: Jurassic– carried out physicogeographical investigations in this Early Cretaceous (Kryshtofovich, 1916, 1921, 1923). region in 1861, was the first to report on the geological Prynada (Kryshtofovich and Prynada, 1932; Prynada, structure of the peninsula. The subsequent investiga 1937, 1939, 1941) and Shtempel’ (1924, 1926) contin tions by M.A. Klykov, P.V. Margaritov, and other ued geological and phytostratigraphic investigations in researchers provided information on the geological the MuravyovAmurskii Peninsula area. structure of some of its areas and collections of mollusk Krassilov (1967) contributed much to the study of and plant remains, which were handed to the Society Cretaceous sections and their plant remains. This for the Study of the Amur Region. In 1908–1912, the researcher and Evlanov (1962) investigated and works by Vittenburg (1910, 1911, 1916) began the new described Lower Cretaceous sections in the Bogataya, stage in the geological investigation of the Muravyov Peschanka, and Saperka river basins. Simultaneously, Amurskii Peninsula and surrounding islands. He col Burde (1961) conducted geological mapping in the lected diverse phytofossils from coastal sections on Vladivostok area. Krassilov (1967) developed the Cape Firsova (Vladivostok, Vtoraya Rechka area) and stratigraphic scale for the Cretaceous deposits of the in Brazhnikov Bay of the Markovskii Peninsula Razdol’naya Depression, which is subdivided into the (Okeanskaya railway station). Kryshtofovich (1910, Ussuri (Barremian), Lipovtsy (Aptian), and Galenki 1916, 1919, 1921, 1923) defined in this collection two (Albian) formations and undivided Korkino Group differentage floras: Montugai (Triassic) and Nikan (Cenomanian). Such a subdivision of Cretaceous sec (Jurassic–Cretaceous). In 1922, M.K. Elishevich tions in Primorye has remained unchanged for almost gathered a representative collection of the Cretaceous half a century. Subsequently, N.G. Melnikov (1991) flora on the MuravyovAmurskii Peninsula, which at investigated the geological structure of the Vladivostok present is stored at the Arseniev State Museum of Pri industrial cluster, which was continued by T.K. Kutub morsky Region (Vladivostok). Most plants from this Zade (KutubZade et al., 2002), A.F. Lysyuk, and 281 282 VOLYNETS a k 132° N n N e Saperka R. K1lp n n 30 d o de Vries Peninsula si ro s o re g gl p lp d e P 1 ° ′ o esc 1 K 43 15 P D ha K K kr y nka gl 1–2 R. 1 E Ba K s la u r u 44 1 u s 42 K in l T3 Am n g e K1 P 48/57, 9 ii 25 k 48/14 rs Cape Firsov u K kr m 1–2 gl A 1 s u v K o 1 y K v a 30 r y u Cape Vyazkii T M Ba 3 ri Vladivostok u ss 41 U 1500 m 43 K lp 40 1 47, 47/1 gl K 1 Cape Spornyi 38, 39 K1–2kr P2 gl Cape Markovskii 1 20 K 77 T3 116 lp K 1 50 115 20 T T Sokol Bay 3 1–2 27, 28 K1us Cape Klykov T 45 26, 26/1–7 3 60 T 110–111 3 112–113 R. taya Boga 0 250 m Brazhnikov Bay P2 12345678 910 45 43 Fig. 1. Schematic geological map of the Podgorodnenka Depression of the MuravyovAmurskii Peninsula (Evlanov, 1962; KutubZade et al., 2002; this work). Rocks: (1) Upper Permian (P2); (2) Lower–Middle Triassic (T1–2); (3) Upper Triassic (T3); (4) Lower Cretaceous, Ussuri Formation (K1us); (5) Lower Cretaceous, Lipovtsy Formation (K1lp); (6) Lower Cretaceous, Galenki Formation (K1gl); (7) Lower–Upper Cretaceous, Korkino Group (K1–2kr); (8) Cenozoic; (9) attitude elements; (10) locality number. E.B. Volynets (2005, 2006, 2009). They collected outskirts of Vladivostok were described as a new spe abundant plant remains and additionally examined cies Nilssoniocladus anatolii Volynets (Volynets, 2010). Cretaceous sections on the MuravyovAmurskii Pen The purpose of this work is to summarize the exten insula. Lysyuk was the first to find impressions of sive geological and paleobotanic data obtained in the shoots with Nilssonia leaves. Isolated leaves of these course of investigations on the MuravyovAmurskii cycadaleans are frequent in many localities, whereas Peninsula since the beginning of the 1980s. impressions of their shoots with leaves are rare. Japa nese paleobotanists Kimura and Sekido (1975) were MATERIAL the first to describe such shoots from the Lower Creta The geological description of Cretaceous sections of ceous section of Japan, attributing them to a new the MuravyovAmurskii Peninsula and collections of genus Nilssoniocladus. Spicer and Herman (1996) also their plant remains served as factual material for this described new species of this genus from the Albian of study (Fig. 1). The study of sections and sampling of Alaska and Albian–Cenomanian of northeastern Rus phytofossils were carried out with my participation in sia. Takimoto et al. (1997) described two new species the period of 1986–2012 by many researchers: geolo from Jurassic strata of Honshu Island. The impres gists A.F. Lysyuk, V.F. Lushnikov, A.V. Oleinikov, sions of shoots from the Lipovtsy Formation in the V.V. Golozubov, paleobotanists E.V. Bugdaeva, STRATIGRAPHY AND GEOLOGICAL CORRELATION Vol. 23 No. 3 2015 CRETACEOUS DEPOSITS AND FLORA OF THE MURAVYOVAMURSKII PENINSULA 283 V.S. Markevich, M.V. Cherepanova, T.A. Kovaleva, and (4) Massive mediumgrained sandstones. The voluntary assistants Yu.A. Semeikin, I.M. Nikulina, thickness is 8.0 m. V.R. Meshcheryakov, N.P. Sologub, and V.V. Yuferov. (5) Massive finegrained sandstones with remains of The collection of plant remains numbers approximately Equsetites sp., Coniopteris (Dicksonia) burejensis, Ony 3000 specimens from 40 localities, including 10 locali chiopsis psilotoides, Adiantopteris yuasensis, Podocarpus ties in the Ussuri Formation (Samples TV48/5, 6, 7, nicanicus, and Pseudolarix dorofeevi (Sample TV112). 9,109–113, 77), 21 localities from the Lipovtsy Forma The thickness is 0.5 m. tion (Samples TV25, 26, 26/17, 27, 27/1, 28, 47, (6) Massive mediumgrained sandstones. The 47/1, 43, 48/14), 7 localities in the Galenki Formation thickness is 2.0 m. (Samples TV41, 41/1, 2, 3, 115, 115/1), and 8 locali (7) Coaly siltstone. The thickness is 0.4 m. ties in the Korkino Group (Samples TV38, 39, 39/1, (8) Alternating mediumgrained crossbedded 40, 42, 44, 116, 116a). Over 100 samples were taken for sandstones and thinbedded siltstones with plant palynological analysis, 50 samples from carbonate detritus, thin coal intercalations (0.1 m) with rare intercalations for microfaunal investigations, and remains of Coniopteris sp. and Onychiopsis psilotoides 40 samples from coal seams for cuticular analysis. All (Sample TV111). The thickness is 15.0 m. the phytofossils are stored in the Laboratory of Paleo botany of the Institute of Biology and Soil Science (9) Compact massive greenish gray medium to (Vladivostok) (collection no. 325). In addition, samples coarsegrained sandstones (2.0 m) grading into silt with Cretaceous plant remains from collections by stones with rare plant remains Gleichenites sp., Ony P.V. Wittenburg (no. 612) and M.K. Elishevich (no. 611) chiopsis psilotoides, Podozamites ex gr. lanceolatus stored at the Arseniev State Museum of Primorsky (Sample TV110). The thickness is 3.0 m. Region (Vladivostok) were used in this study. (10) Alternating finegrained sandstones and thin bedded siltstones with plant remains: Lycopodites prynadae, Coniopteris sp., Onychiopsis psilotoides, Ruf GEOLOGICAL DESCRIPTION fordia goeppertii, Adiantopteris yuasensis, A. sewardii, OF CRETACEOUS DEPOSITS Cladophlebis denticulata, Sagenopteris sp. Nilssoniopt ON THE MURAV’EVAMURSKII PENINSULA eris sp., Podozamites ex gr. lanceolatus, P. tenuinervis, Pagiophyllum orientalis (Sample TV109). The thick The MuravyovAmurskii Peninsula represents a ness is 8.0 m.