Diatom community and palaeoenvironmental properties of Karacaoren diatomite deposits (Nevşehir, Central Anatolia, Turkey)

WOS: 000412609000024The diatom community and palaeoenvironmental properties of volcano genetic diatomite deposits that outcrop in the Karacabren (Nevehir) area are described. Two stratigraphic sections were measured in the study area. One of these sections was measured in Quaternary lake units (K1), and the other in lacustrine sediments of the late Miocene -Pliocene Urgup Formation's Bayramhaoh Member (K2). According to stratigraphic and chemical characteristics of the sections, two distinct paleogeographic domains were determined in the study area. One of these, the shallow lacustrine to fluvial area (Quaternary) which is represented by an alternating sequence of diatomite, silt/mud, and tuffite. The other was the deeper lacustrine stage (late Miocene) which is represented by diatomites with some interbedded mud fades, chert and volcanics. From the diatomite samples of these sections, twenty-five species of 10 different diatom genera were identified. When evaluated together, the ecological properties and the distribution of numerical values of the determined diatom genera and species, showed that the study area's diatomite was generally deposited in shallow, high temperature, nutrient-rich water, where nitrogen and phosphorus were abundant and which was an alkaline (pH > 7) freshwater lake environment. Over time the pH value of the environment decreased (pH < 7), and the environment became acidic. (C) 2017 Elsevier Ltd. All rights reserved.Aksaray University Scientific Research Foundation (ASU-BAP) [2012/16]; Scientific Research Projects Coordination Unit of Aksaray UniversityThis study was performed within the 2012/16 numbered Scientific Research Project supported financially by the Aksaray University Scientific Research Foundation (ASU-BAP). We gratefully acknowledge financial support for this study from the Scientific Research Projects Coordination Unit of Aksaray University