Authors
1
M. Sc. (graduated), Dept., of Geology, Faculty of Sciences, University of Zanjan, Zanjan, Iran
2
Assoc. Prof., Dept., of Geology, Faculty of Sciences, University of Zanjan, Zanjan, Iran
3
Assist. Prof., Dept., of Geology, Faculty of Sciences, University of Zanjan, Zanjan, Iran
Abstract
The Qanli laterite-bauxite horizon is located in the Central Iranian Zone, at a distance of 80 km from Zanjan city. The studied units at this area include sequences of the Ruteh and the Shemshak Formations. Based on sedimentary facies analysis and study of skeletal and non-skeletal allochems, it can be concluded that the sedimentary environment of this formation is a ramp-type carbonate platform. According to the fieldwork studies, the Qanli laterite-bauxite horizon is stratiform and and located at the final section of the Ruteh and below the Shamshak Formation. Mineralogical studies show that the laterite-bauxite horizon consists of hematite, goethite, boehmite and kaolinite with a few amounts of lipdocrosite, rutile, chlorite and ilmenite. Microgranular, pletiomorphic, flow-colloform, pisoidic, ooidic, peloidic and extraclast are the most important textures in these strata. Different chemical diagrams show that the laterite-bauxite horizon of Qanli deposit is located in the range of bauxite, bauxite clay and laterite. According to the mineralogical studies, it seems that the formation of laterite-bauxite horizon of Qanli occurred at pH between 3.5 to 6 and Eh about 0.4 to 0.7 and it has undergone moderate degrees of lateritization process. Current research indicate that the laterite-bauxite horizon of Qanli is the most similar to the karst bauxite deposits. Due to the expansion of Permian and Jurassic units in this area and nearby areas, the study and investigation of the Qanli laterite-bauxite horizon can be considered as an exploration key for similar areas in the Central Iranian zone.
Keywords
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