The Arzular mineralization is one of the best examples of epithermal gold deposits in the eastern Pontides orogenic belt. The mineralization is hosted by the subduction-related basaltic andesites and is mainly controlled by E-W and NE-SW trending fracture zones. The main ore minerals are galena, sphalerite, pyrite, chalcopyrite, tetrahedrite and gold. Homogenization temperatures of fluid inclusions are between 130 and 295 degrees C for quartz and between 90 and 133 degrees C for sphalerite. Sulphur isotope values obtained from pyrite, galena and sphalerite vary between -1.2 parts per thousand and 3 parts per thousand, indicating that sulphur belongs to magmatic origin and was derived from the Lutetian non-adakitic granitic intrusions in the region. Oxygen isotope values are between 15.0 parts per thousand and 16.7 parts per thousand, and hydrogen isotope values are between -87 parts per thousand and -91 parts per thousand. The sulphur isotope thermometer yielded temperatures in the range of 244-291 degrees C for the ore formation. Our results support the hypothesis that the Arzular mineralization is a low-sulfidation epithermal gold deposit associated with non-adakitic subduction-related granitic magmas that were generated by slab window-related processes in a south-dipping subduction zone during the Lutetian. (C) 2013, China University of Geosciences (Beijing) and Peking University. Production and hosting by Elsevier B.V. All rights reserved.