Coal features and depositional environment of the Northern Karapınar-Ayrancı coal deposit (Konya, Central Turkey)

Authors : Riza Görkem OSKAY, Kimon CHRISTANIS, Mert SALMAN

Pages : 260-274

View : 21 | Download : 6

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The Karapınar-Ayrancı deposit is the most significant one among the recently explored coal deposits in Turkey. The aim of the present study was to determine maceral, mineralogical, and elemental compositions of coal samples picked up from one borehole insert ignore into journalissuearticles values(DK-7); drilled at the northern part of the deposit. The coal samples display moderate to high ash yield insert ignore into journalissuearticles values(average 38.7%, on dry basis);, high volatile matter yield insert ignore into journalissuearticles values(average 33.9%, on dry basis);, high total sulfur insert ignore into journalissuearticles values(average 6.7%, on dry basis); and low hydrogen contents insert ignore into journalissuearticles values(average 4.8%, dry basis);. Huminite is dominant, and liptinite and inertinite appear at low concentrations. The bulk coal samples contain mainly quartz, clay minerals insert ignore into journalissuearticles values(mainly illite and chlorite);, muscovite, feldspars, carbonates insert ignore into journalissuearticles values(calcite and aragonite);, and rarely pyrite and gypsum/bassanite. The maceral and mineralogical compositions point to mesotrophic and rheotrophic conditions during peat accumulation; nevertheless, the inorganic intercalations show that peat formation was ceased several times. The petrographical and mineralogical compositions of coal seams in northern and eastern parts of the deposit could imply vegetation and water chemistry differences. The abundance of fossil shell-bearing layers in the studied samples could imply a slightly higher water table than this in the eastern part. In addition, higher telohuminite content might be related to a higher contribution of tree/bush peat-forming vegetation in the northern part; however, the lack of xylite-rich lithotype and the abundance of fluorinite-type resinite imply the predominance of shrubs on the palaeomire`s surface. Overall, the precursor peat in the northern part of the deposit was accumulated under pure telmatic to limnotelmatic conditions, vegetation heterogeneity and ditches transporting inorganic material from the margins were developed on the surface of the Karapınar-Ayrancı paleomire.
Keywords : Karapınar Ayrancı, maceral composition, coal, peat forming environment, coal facies, Konya Graben