Early Miocene palaeoflora and palaeoecology of the Soma Basin, Western Turkey

In this study comprehensive palaeofloristic data of lower Miocene deposits from the Soma Basin, western Anatolia is presented considering the stratigraphical concept. The sediments of the basin, derived from outcrop sections, were deposited in the terrestrial environment. The basin includes three different successions: lower and middle lignite successions of the Soma Formation and upper lignite succession of the Denis Formation. In this paper, we address the early Miocene palaeoecology via pollen and leaf assemblages from the Soma Basin, dated precisely using radiometric data. High percentages of Cupressaceae in the lower lignite succession of the Soma Formation, and minor quantities of elements such asCarya,Nyssa,Myrica,UlmusandSalixreflect a local riparian and swamp vegetation. Marls overlying the lower lignite succession represent an environment close to the source area, with a variety of flora. During the deposition of middle lignite succession wet conditions played an essential role in the swamp forest fostering some distance transport of pollen which reflect the mesophytic forest vegetation as well as higher altitudes in the hinterland. The high percentages of lacustrine planktonBotryococcusand presence ofSpirogyrain the upper lignite succession of the Denis Formation imply a shallow water environment with less rainfall surrounded by evergreen and deciduous mixed forest.