Sedimantological and geochemical properties of tufa stocks in the environment of Aktuluk (Tunceli)

The study area is connected to the central district of Tunceli and is around Aktuluk village which is 8 km away from the center. The region is located in the Eastern Anatolian Taurus Orogenic Belt. Basic rocks of the study area; Permian aged Karşılar Formation, Paleocene-Eocene Tunceli Formation, Miocene Kocakoç Formation, Miocene-Pliocene Mazgirt Volcanics, Quaternary aged scales. Tufa deposits are unconformably overlain by Paleocene-Eocene flysch sediments in the middle and south of the study area and are partly laterally and vertically related to the Munzur River Terraces (conglomerates). 7 sections were measured from the outcrops where facies were well observed. In addition, the location of the steep places can not be taken by specifying the characteristics of the sequence is given. As a result of the investigation of sedimentological features of the scales, 14 facies were defined. These are: (1) Phytoherm limestone, (2) Stromatolithic tufa (Phytoherm context stone), (3) Moss (bryophytes) phytoherm limestone, (4) Phytoclastic limestone, (5) Intra-clastic limestone, (6) Bioclastic limestone (Biomicrite), ( 7) Spelotem limestone (stalactite, stalagmite and crystalline crust subfacies), (8) Carbonate breccia, (9) Marl, (10) Mudstone, (11) Paleosol, (12) Laminated sandstones, (13) Planar cross-bedded sandstones are massive conglomerates. Stable C and O isotope values of 20 samples taken from Aktuluk scales were analyzed. δ13C values range from 1.80 to 5.03; δ18O values range from -9.96 to -8.84. In this study, high values of 13C in tufa samples indicate that shallow circulating cold waters and deeper thermal waters are mixed. Waters with temperatures above 20 ° C are defined as thermal waters. Major and minor element analyzes of 10 tufa samples taken from different levels and different locations were performed in the study area. The concentration of Ca, which is one of the main elements, is high and the average is 40%. The highest value (53.60%) was reached in brofit tufa facies and the lowest value (38.26%) was reached in spelotem (flowstone / crystalline crust) facies. Fe, Mn and Ba values of all samples in the study area are low and below 1%. According to U / Th age data, Aktuluk scales were deposited in Middle-Late Pleistocene. According to the U / Th ages obtained from the scales; tufas were deposited in both glacial (MIS 5) and glacial (MIS 6) periods. MIS 5 is a rainy and warm period; thus it is a suitable period for tufa formation. For the tufa formations in MIS 6 (147.442-164.357 thousand years), interstadials (short-term warm periods within a glacial period) within the MIS-6 can be envisaged. As a result of the evaluation of the data obtained, the sediments were deposited in barrier-lake, waterfall-river and swamp environments. Key Words: Tufa, Facies, Geochemical Properties, SEM, U-Th, Stable Isotope, Elemental Analysis, Tunceli.