Maden, N.; Akaryali, E.; Aydınçakır, E.

Eastern Pontide orogenic belt located in the Alp-Himalayan fold belt is divided into three subzones such as northern, southern and axial zones. These zones are controlled by the NE, NW and E-W directed fault systems. The study area whose geodynamic evolution is still debated is situated in the southern zone of the Eastern Pontide Orogenic belt. The views proposed for the geodynamic evolution of the eastern Pontides can be grouped into three. The geodynamic evolution of the region and genesis of the volcanic rocks are evaluated with a total 305 gamma ray spectrometer measurements surveyed at the Tertiary aged rocks in the Gümüşhane area. Total abundances of thorium ranges from 0.12ppm to 2.97 ppm, from 0.27ppm to 2.32 ppm for uranium, and from 0.09 % to 8.72 % for potassium. The average contents of radioelement concentrations computed over all measurements is: 0.85 (±0.33sd), 1.2(±0.54sd) ppm and 0.57 (±0.63sd) %, for U, Th and K, respectively. Numerical results verify that the parental magma of the Tertiary aged volcanic rocks probably derived from an enriched mantle originated from upper continental crust, previously metasomatized by subducted derived fluids..

Maden, N.

The Black Sea is a marginal sea represented by the Caucasus to the east, by the Balkanides-Pontides to the south and southwest, the Crimean Mountains to the north, and young platforms (Moesian and Scythian) to the west and northwest.The Black Sea basin is divided into two parts, Western and Eastern, separated by the Mid Black Sea ridge.The origin of the eastern Black Sea basin and Pontides orogenic belt is still controversial due to lack of systematical geological, geophysical and geochemical data. It is widely accepted that the eastern Pontides orogenic belt was shaped by northward subduction of Neotethys or Paleotethys oceanic lithosphere during the late Mesozoic and the Black Sea basin opened as a back-arc basin behind the eastern Pontides magmatic arc. In this study, the tectonic elements of the Black Sea basin are investigated by using satellite gravity data.The time of formation of Black Sea basin occurred from Paleozoic to Mesozoic, showing the Black Sea is a remnant of the Paleotethys Ocean.The numerical studies give the indication of southward subduction model for the origin of the Pontides during late Mesozoic-Cenozoic and compressional tectonic regime is still active in the Eastern Black Sea region.

Maden, N.; Akaryali, E.

The gamma ray spectrometry has been widely used in mineral exploration, geological mapping and environmental radiation monitoring.The Eastern Pontide orogenic belt, which constitutes an important part of the Alpine-Himalayan system, hosts various types of economic mineral deposits of massive sulfide, porphyry copper, skarn, and epithermal vein-type ore deposits. Potassium is generally the most useful pathfinder element for gold mineralization zones. High level K/eTh, K/eU and Efimov F-Parameter (KeU/eTh) anomalies showed the alteration zones transmitting hydrothermal ore solutions to the surface. As a result, the gamma ray spectrometry, which is fast and economics method, might be used for estimation of prospective Au ore zones associated with the K alteration.