Petrified wood samples are found within terrestrial sediments belonging to the Late Oligocene-Early Miocene Danişmen Formation in Malkara-Keşan located in the southwest of the Thrace Basin. The petrified wood in both regions is usually silicified and partly coalified. The silicification of the Tertiary wood in the Malkara-Keşan region is associated with volcanic activity and coeval sedimentation. Thin sections from petrified wood samples were taken as transverse, tangential, and radial sections. The mineralogicalpetrographic-botanical studies were carried out under a polarizing and botanical microscope. Opal-moganite-chalcedony-quartz, which are different polymorphs of silica, were detected under the microscope in the petrified wood. | Turkish Journal of Earth Sciences Turkish J Earth Sci 2022 31 49-70 http earth TÜBİTAK Research Article doi yer-2106-2 Mineralogical and paleobotanical investigations of Oligo-Miocene petrified wood from the southwest of Thrace Basin NW Turkey 1 2 3 Burcu ÇEVİK ÜNER Sabah YILMAZ ŞAHİN Ünal AKKEMİK 1 Department of Geological Museum Faculty of Engineering İstanbul University-Cerrahpaşa İstanbul Turkey 2 Department of Geological Engineering Faculty of Engineering İstanbul University-Cerrahpaşa İstanbul Turkey 3 Department of Forest Botany Faculty of Forestry İstanbul University-Cerrahpaşa İstanbul Turkey Received Accepted Published Online Final Version Abstract Petrified wood samples are found within terrestrial sediments belonging to the Late Oligocene-Early Miocene Danişmen Formation in Malkara-Keşan located in the southwest of the Thrace Basin. The petrified wood in both regions is usually silicified and partly coalified. The silicification of the Tertiary wood in the Malkara-Keşan region is associated with volcanic activity and coeval sedimentation. Thin sections from petrified wood samples were taken as transverse tangential and radial sections. The mineralogical- petrographic-botanical studies were carried out under a polarizing and botanical microscope. Opal-moganite-chalcedony-quartz which are different polymorphs of silica were detected under the microscope in the petrified wood. Results were supported by X-Ray Diffractometer XRD Confocal Raman Spectroscopy Fourier Transform Infrared Spectroscopy FT-IR analysis and measurement of density in a total of five samples. In addition scanning electron microscopy SEM EDS was performed for textures and to determine the average elementary composition of wood samples. Results showed that while crystalline quartz and chalcedony were well defined opal-A and other polymorphs of silica could be partly examined due to isotropic features. As a result of XRD .
