Palaeoecology of Coal-Bearing Eocene Sediments in Central Anatolia (Turkey) Based on Quantitative Palynological Data

In this study, the lignite-bearing Yoncali formation between Yozgat and Sorgun, in central Anatolia has been palynologically examined. Based on 37 outcrop samples, quantitative palynological studies recognized 64 genera and 136 palynoflora species in the palynological assemblage, which indicated a Middle-?Late Eocene age. This paper also presents a quantitative palaeovegetation and palaeoclimate reconstruction for the Middle-?Upper Eocene coal occurrences of Central Anatolia on the basis of palynomorph assemblages. The diversified floral and ecological characteristics of the pollen taxa indicates that the Middle-?Upper Eocene formations in central Anatolia were characterized by the presence of a complex mangrove swamp with contributions by Nypa, Pelliciera, Avicennia, Diporites iszkaszentgyorgyi and dinoflagellate cysts which reflect warm climatic conditions. Behind the mangrove zone, pollen of Restionaceae, Ephedraceae, Mauritia, Proxapertites (Araceae) and Longapertites (Arecaceae) as well as the fern Acrostichum aureum occur. Lowland-riparian and montane elements are characterized by the dominance of Myricaceae, Symplocaceae, Icacinaceae, Quercus, Pinus and Castanea. Swamp-freshwater elements are represented by Sparganiaceae, Nymphaceae, Taxodiaceae, Cupressaceae and Nyssa as well as fern spores such as Osmundaceae and Gleicheniaceae. The calculations were performed with the help of the `Coexistence Approach´ method to climatically evaluate palynoflora from the Yozgat-Sorgun area. The obtained results have been compared to data derived from the application of the Coexistence Approach to other, already published Central Anatolian palynofloras of the same age. The results of the climatic inferences suggest that the palaeoclimatic conditions were in the megathermal zone (mean annual temperature of 24.8-25 oC), megatherm/mesotherm intermediate zone (mean annual temperature of 23.1-24.8 oC near the coast) whereas mesothermic (mean annual temperature of 16.5-23.1 oC) conditions prevailed in the montane region. Likewise, the results of mean annual range of temperatures indicate the influence of the Indian ocean, which enabled the development of the mangroves.

[1]  N. Shackleton,et al.  Paleotemperature History of the Cenozoic and the Initiation of Antarctic Glaciation: Oxygen and Carbon Isotope Analyses in DSDP Sites 277, 279 and 281 , 1975 .

[2]  Nuretdin Kaymakçi,et al.  Post - collisional tectonics of Eskisehir - Ankara - Cankiri segment of Izmir - Ankara - Erzincan Suture zone IAESZ : Ankara orogenic phase , 1995 .

[3]  W. L. Kovach.  Comparisons of multivariate analytical techniques for use in pre-quaternary plant paleoecology , 1989 .

[4]  E. M. Friis,et al.  The Origins of Angiosperms and their Biological Consequences , 1988 .

[5]  B. Erdoğan,et al.  Geology of the Yozgat Region and Evolution of the Collisional Cankiri Basin , 1996 .

[6]  N. Frederiksen.  Sporomorphs from the Jackson Group (upper Eocene) and adjacent strata of Mississippi and western Alabama , 1980 .

[7]  M. Pole,et al.  Eocene Nypa from Regatta Point, Tasmania , 1996 .

[8]  C. V. Steenis,et al.  The land-bridge theory in botany , 1962 .

[9]  V. Rull.  Biogeographical and evolutionary considerations of Mauritia (Arecaceae), based on palynological evidence , 1998 .

[10]  N. Frederiksen.  Mid-Tertiary climate of southeastern United States; the sporomorph evidence , 1980 .

[11]  V. Rull.  Middle Eocene mangroves and vegetation changes in the Maracaibo Basin, Venezuela , 1998 .

[12]  V. Ediger,et al.  Paleopalynology and paleoecology of Calamus-like disulcate pollen grains , 1990 .

[13]  R. Gayer,et al.  Quality, palynology, and palaeoenvironmental interpretation of the Ilgin lignite, Turkey , 1999 .

[14]  James W. Westgate,et al.  Paleoecology of a middle Eocene mangrove biota (vertebrates, plants, and invertebrates) from southwest Texas , 1990 .

[15]  V. Rull.  Evolución de los manglares neotropicales: la crisis del Eoceno , 1998 .

[16]  W. L. Kovach.  Quantitative palaeoecology of megaspores and other dispersed plant remains from the Cenomanian of Kansas, USA , 1988 .

[17]  J. Ellison.  Pollen analysis of mangrove sediments as a sea-level indicator: assessment from Tongatapu, Tonga , 1989 .

[18]  V. Mosbrugger,et al.  The coexistence approach — a method for quantitative reconstructions of Tertiary terrestrial palaeoclimate data using plant fossils , 1997 .

[19]  F. Akgün,et al.  Tertiary Terrestrial to Shallow Marine Deposition in Central Anatolia: A Palynological Approach , 2002 .

[20]  J. A. Wolfe.  A Paleobotanical Interpretation of Tertiary Climates in the Northern Hemisphere , 1978 .

[21]  J. A. Wolfe.  Temperature parameters of humid to mesic forests of Eastern Asia and relation to forests of other regions of the Northern Hemisphere and Australasia: analysis of temperature data from more than 400 stations in Eastern Asia , 1979 .

[22]  J. Plaziat,et al.  History and biogeography of the mangrove ecosystem, based on a critical reassessment of the paleontological record , 2001, Wetlands Ecology and Management.

[23]  F. E. Egler.  Ecosystems of the World , 1960 .

[24]  M. Kedves,et al.  Paleogene fossil sporomorphs of the Bakony mountains , 1973 .

[25]  Harold V. Kaska.  A spore and pollen zonation of Early Cretaceous to Tertiary nonmarine sediments in central Sudan , 1989 .

[26]  V. Rull.  Palaeofloristic and palaeovegetational changes across the Paleocene/Eocene boundary in northern South America , 1999 .

[27]  González Guzmán.  A palynological study on the upper Los Cuervos and Mirador formations : lower and middle eocene : Tibú area, Colombia , 1967 .

[28]  W. Berggren,et al.  Eocene-Oligocene Climatic and Biotic Evolution , 1992 .

[29]  V. Mosbrugger,et al.  Cenozoic continental climatic evolution of Central Europe. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[30]  R. Huene,et al.  Initial reports of the deep sea drilling project: National Science Foundation, Washington, D.C., 1969, 672 pp., U.S. $ 10.25 , 1971 .

[31]  G. Norris.  Systematic and strataigraphic palynology of Eocene to Pliocene strata in the Imperial Nuktak C-22 well, Mackenzie delta region, District of Mackenzie, Northwest Territories , 1986 .

[32]  O. Lenz,et al.  Isopollen maps as a tool for the reconstruction of a coastal swamp from the Middle Eocene at Helmstedt (Northern Germany) , 2001 .

[33]  D. Greenwood,et al.  Eocene continental climates and latitudinal temperature gradients , 1995 .

[34]  D. Pocknall.  Palynological evidence for the early to middle Eocene vegetation and climate history of New Zealand , 1990 .

[35]  V. Rull.  Ecostratigraphic Study of Paleocene and Early Eocene Palynological Cyclicity in Northern South America , 2000 .

[36]  T. Hammen,et al.  A palynological study on the Quaternary of British Guiana , 1963 .

[37]  J. A. Wolfe.  21. Climatic, Floristic, and Vegetational Changes near the Eocene/Oligocene Boundary in North America , 1992 .

[38]  C. Ager,et al.  Distribution, paleoecology, paleoclimatology, and botanical affinity of the Eocene pollen genus Diporoconia n. gen. , 1985 .

[39]  O. Lenz,et al.  The Paleoecology of the Lower and Middle Eocene at Helmstedt, Northern Germany - A study in Contrasts , 1999 .

[40]  J. Muller,et al.  Palynology of tertiary sediments from tropical areas , 1968 .

[41]  A. Graham,et al.  Vegetation and Vegetational History of Northern Latin America. , 1975 .

[42]  M. S. Akkiraz,et al.  Stratigraphic and Palaeoenvironmental Significance of Bartonian–Priabonian (Middle–Late Eocene) Microfossils from the Başçeşme Formation, Denizli Province, Western Anatolia , 2006 .

[43]  D. K. Goodman.  Dinoflagellate “communities”; from the lower Eocene Nanjemoy formation of Maryland, U.S.A. , 1979 .

[44]  V. Mosbrugger,et al.  Palynological evidence for Miocene climate change in the Forecarpathian Basin (Central Paratethys, NW Bulgaria) , 2002 .

[45]  K. S. Kavak,et al.  Tectonic Setting and Evolution of the Sivas Basin, Central Anatolia, Turkey , 1996 .

[46]  J. Gray.  Temperate Pollen Genera in the Eocene (Claiborne) Flora, Alabama , 1960, Science.

[47]  Carla Cavagnetto,et al.  Preliminary palynological data on floristic and climatic changes during the middle Eocene-Early Oligocene of the eastern Ebro Basin, northeast Spain , 1996 .

[48]  J. Jiménez.  A Hypothesis to Explain the Reduced Distribution of the Mangrove Pelliciera rhizophorae Tr. & Pl. , 1984 .

[49]  Yücel Yılmaz,et al.  Tethyan evolution of Turkey: A plate tectonic approach , 1981 .

[50]  T. Hammen,et al.  A palynological study on the Tertiary and Upper Cretaceous of British Guiana , 1964 .

[51]  L. Stover,et al.  New genera and species of early Tertiary palynomorphs from Gulf Coast , 1966 .

[52]  G. G. Fechner.  Selected palynomorphs from the lower to middle eocene of the South Atlas Border Zone (Morocco) and their environmental significance , 1988 .

[53]  C. Gee,et al.  The mangrove palm Nypa in the geologic past of the New World , 2001, Wetlands Ecology and Management.