Geochemical stratigraphy of the Karakaya non-sulphide Zn-Pb deposit, Hakkari, SE Turkey

Abstract

The Karakaya non-sulphide Zn-Pb deposit occurs within a sequence of Middle-Upper Triassic-Jurassic carbonates. The deposit consists of three main parallel ore zones each with an average thickness of 2.5 m. The ore consists of smithsonite, hemimorphite, zincite/hydrozincite, goethite, hematite, cerussite and anglesite. This study details trace element behaviour throughout the 30 m thick sequence of the third ore zone. The average TI, As, Hg, Sb, Mo, Mn and Ba content of the associated carbonates are 13,49, 0.25, 2, 4, 2970 and 1454 ppm, respectively. These values are much higher than the average of marine carbonates (0.14,2.6, 0.04, 1.5, 2, 0.055, and 10 ppm). The average content of the TI, As, Hg, Sb, Se, Mo, Mn and Ba in the 13 ore levels of the third ore zone are 301, 3938, 15, 114, 3, 90, 5629, and 1189 ppm, respectively. The enrichment of the same trace elements in the both ore and associated carbonates suggests a repeated hydrothermal discharge into a sedimentary basin. Trace element-rich ore and carbonates imply a metal-rich pool where the TI, As, Hg, Sb and Mo precipitated at a basin scale. These trace element associations are more indicative of SEDEX-type mineralization not MVT or Irish-type Zn-Pb deposits.