Jeoloji Münendisliği Dergisi

Malatya-Yeşilyurt Gold-Bearing Fluorite Mineralization: A Paleokarst Type Deposit in Eastern Taurides, "Turkey

ABSTRACT: The gold-bearing fluorite mineralizations are observed along the contacts between Devonian/?)- Carboniferous crystallized limestone of Malatya metamorphics and Permian schists, which unconformabfy overlie the former. The thickness of mineralization varies from 1 m to 30 m and the ore bearing zone may attain up to 10 km lengths along the unconformity surfaces. The lithological composition of the ore hearing zone is represented by conglomerate/breccia. The matrix: of breccia is mainly composed of quartz, fluorite and limoniie, The rock and ore fragments within the breccia are crystallized limestone, schist, chert and fluorite. Due to its high silica content, ore bearing zone present a different kind of morphology compared to surrounding rocks. Two different morphological features are present (1) unconformity-concordant, flat-lying and more or less tabular bodies (2) conical bodies extending downwards in the form ofkarstic cavity-fillings and they become narrower as they extend downwards.. The gold content of ore-bearing zone is highly variable.. The gold contents of the breccia ore containing graphitic organic material, reach up to 12,5 ppm. However, when there is no breccia texture and fluorite, the gold content gets much lower and decreases down to 100 ppb. In terms of geological position, structural-textural features, and mineral content, the Malatya-Yeşüyurt gold-bearing fluorite mineralization is a paleokarst type deposit formed on the imcorformity surfaces and believed to have been formed by karstification process thaï has continued in the region since Laie Eocene. Units consisting clay, sand and carbonate, which is overlying orebearing zone are favored as the most likely source of gold-bearing fluorite mineralization.. It is assumed that the components that formed the mineralization have been carried to the enriching environment by means of solutions that move deep down under gravity control Meanwhile, goldbearing fluorite mineralization is the first ever known mineralization its formation is based on karstification process at the Eastern Taurus Belt and whose distrubition is controlled by the uncorformity surfaces. Hence when its geological position and extension are concerned, this type of mineralization seems to be extremely important to form a basis for Jurther exploration studies in the Eastern Taurus Orojenic Belt.