Kines, M. Tuncay (1969) The geology and the ore mineralization in the Keban area, east Turkey. Doctoral thesis, Durham University.
The Keban mine is one of the most important lead and zinc producers in Turkey. It is located 54 km NW of Elazig County, Eastern Turkey.
The Keban metamorphic massif consists of calc-schists, dolomite marble, phyllite and marble. It forms part of the eastern Taurid belt, a prolongation of the Alpine orogenic belt.
The principal structural feature of the area is the northern extension of the Malatya-Keban anticline, a major recumbent fold with a NE-SW axis. Later movements acting in different directions gave rise to N-S, E-W, NW-SE and NE-SW directed folding and faulting over the previous anticline. Small bodies of quartz-syenite porphyry, of paleocene age, intrude the metasediments.
Detailed study by chemistry, petrography and x-ray techniques on sanidine accounts for a composition range between Or65 Ab35 and Or99 Ab1. The ratio of Or to Ab tends to increase outwards from the central parts of the igneous body.
Skarn zones have developed in association with the intrusion of quartz-syenite porphyry. These are located mainly within the metasediments. The magnatite deposit of Zereyandere, the scheelite deposit of Kebandere and the main sulphide deposit were formed as part of the process of skarn formation. Minor amounts of some manganese minerals and the minerals vanadinite and descloizite derived from the main sulphide deposit, are also found in the district.
The main sulphide deposit of economic importance chiefly incudes sphalerite, galena, iron and copper sulphides and several sulfo-salts in subordinate amounts. Of the by-products, silver comes from galena, polybasite and tennantite. Arsenopyrite in addition to chalcopyrite contains trace concentrations of gold. All the evidence suggests that the quartz- syenite porphyry is the source of mineralization. The location of ore minerals is controlled by certain rock types and by major and minor structural elements. Variation of vapour fugacity and temperature during mineralization are indicated by more than one stage of formation for certain ore minerals. The presence of different gangue minerals marks the fluctuating nature of the ore forming fluids whose last stage is believed to be alkaline rather than acidic.
The main sulphide deposit is accepted as a semi-metasomatic contact deposit, while the magnetite and scheelite deposits are classified as being metamorphic.
Using various methods, a temperature range of formation between 620° and 78°C is estimated for the ore minerals of the main sulphide deposit. For the ore minerals of the magnetite and scheelite deposits the range is from 743°C down to 225°C.
|Item Type:||Thesis (Doctoral)|
|Award:||Doctor of Philosophy|
|Faculty and Department:||Faculty of Science > Earth Sciences, Department of|
|Copyright:||Copyright of this thesis is held by the author|
|Deposited On:||05 Apr 2012 12:08|