Investigation of the geological features and commercial marble potential of the region between Emirdağ-Bayat (Afyon) and Han (Eskişehir) districts

This study aims to evaluate the commercial marble potential of sedimentary (dolomite, conglomerate, travertine), metamorphic (marble) and magmatic (welded tuff) rocks spreading in the study area. These rocks can be simply divided into old basement and young cover rocks. Upper Permian marbles and Middle Triassic-Upper Jurassic dolomites and conglomerates derived from dolomites form old basement rocks, Middle Miocene welded tuffs and Middle Miocene travertines form young cover rocks. Sufficient geological conditions for commercial marble production in potential areas are reserve, stability, productivity, color, pattern and homogeneity. Both the basement rocks and the cover rocks have significant reserves with their wide distribution and thickness in the study area. In general, the Anatolian continent was affected by compressional tectonics during the Cretaceous-Paleocene period and extensional tectonics after the Lower Miocene. Old basement rocks were heavily affected by compressional tectonics. As a result, dense joint systems developed in brittle marbles and the productivity and stability potential of the marbles decreased. However, in some parts of dolomites and dolomitic conglomerates that behave more elastically, joint systems are less developed. In these areas, the productivity and stability potential of massive dolomites and conglomerates is high. Since travertines and welded tuffs are only affected by extensional tectonics, the development of joint systems has been less. Therefore, massive travertines have a high productivity and stability potential for commercial marble. However, since welded tuffs are soft, their durability potential is not sufficient for commercial marble. Marble, dolomite and conglomerates have light and dark shades of gray, while travertines have shades of yellow, cream, gray and silver. Travertines contain large and small pores and holes spread regularly and homogeneously along the layer planes. Dolomites show homogeneous spider web patterns in some areas due to their formation characteristics. The conglomerates have homogeneous appearances where gray dolomite pebbles are bonded with gray carbonate cement. Light and dark colors in marble, dolomite and travertine plates form homogeneous patterns repeated in the form of bands. The color, pattern and homogeneity properties of the marble, dolomite, conglomerate and travertine in the study area are suitable for use as commercial marble. Since the beginning of the 2000 s, increasing demands in domestic and foreign markets have increased commercial marble exploration and production activities in our country and in the study area. During this period, more than 250 marble exploration license applications have been made on the marble, dolomite, conglomerate and travertine reserves in the study area. Quarry operations have been operating in a small part of these that provide sufficient geological conditions (1 for marble, 16 for dolomite, 2 for conglomerate and 5 for travertine). Most of them have been abandoned or canceled because they did not meet one or more of the sufficient geological conditions. Due to the pandemic, the demand for commercial marble abroad (especially China) has been decreasing since 2020 and there have been decreases in unit prices. This situation has caused many marble quarries to suspend their activities both in the country and in the study area. For this reason, 5 dolomite and 3 travertine quarries continue their activities in the study area. Keywords: Han, Emirdağ, Bayat, commercial marble, economic potential