Document Type : Original Research Paper

Authors

Metalic Exploration Department, Geological Survey of Iran, Tehran, Iran

Abstract

Markasheh occurrence, includes redbed sediments (Garadu Redbeds) of Jurassic-Cretaceous age that extend in a large area for over 400 km in an area. Garadu Redbeds include alternate of red oxidized  sandstone, conglomerate and siltstone that is partly reduced. Mineralization occurred in reduced horizons and is related with paleochannels. In the Markasheh area two obvious main reduced horizons and four sub-horizons occur. Each of these horizons includes three zones: Red oxidized zone, Bleached zone and Reduced mineralized zone. Based on characteristics of Markasheh Cu occurrence such as lithology, lens like and layered shape (in geometry), regional extent, replacement and disseminated textures, simple mineralogy, presence of plant fossils and concentration of copper mineralization in relation to fossils, Markasheh Cu occurrence is considered as a  Red bed sediment-hosted copper deposit type. The mineralization has been occured after early diagenesis before burial of the host roks.

Keywords

 
Refrences
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