Comparative geochemical study of soils developed on characteristic black and yellow polymetallic massive sulfide deposits in Eastern Pontides (NE Turkey)

The Harşit-Köprübaşi{dotless} (Tirebolu) and Killik (Espiye) volcanogenic massive sulfide (VMS) deposits occur in the Eastern Pontide tectonic belt, one of the major tectonic units comprising Anatolia. They are hosted by Late Cretaceous dacitic to rhyolitic rocks overlain by thin layers of pelitic sediments. The region is considered as a metallogenic province since it is a host to numerous VMS deposits, mainly of the Kuroko type, with varying sizes and reserves and with fairly similar geochemical and mineralogical characteristics. In this study, 489 soil samples were systematically collected from both known mineralized sites and remote areas that have no indication of ore mineralization or alteration to investigate the relationship of Zn, Cu, and Pb concentration distributions on 2 completely delineated ore deposits that are treated as natural physical models and on unmineralized distant areas in order to determine regional backgrounds, local thresholds, and anomalous values that are characteristic to the Eastern Pontide metallogenic province to use in exploration programs as a cost-effective prospecting method. Applicability of proposed geochemical modeling based on the results during surficial geochemical prospecting to potential hydrothermally altered areas occurring in the region and elsewhere in the world is discussed. The results were found to be highly convincing if sampling campaigns and data evaluations are cautiously conducted.