Writers : jafarzade,Reza؛Hoseyni Faegh,Mohammad hoseyn
Refference : Proceeding of the first Applied Geological Congress of Iran
Publishing Year : 1386

Abstract :
The Jajarm bauxite deposit is located in northeast of Iran SW north Khorasan province (N37º,2´-37º,3´ and E57º,25´- 57º,45´). This deposit lies in boundary of three Eastern Alborz , Kopet-Dage and East of Iran sedimentary basins, between Two major Faults Kurkhoud Fault in North and Jajarm thrust Fault in South.
A complete sequence of sediments exist in this area ranging from Paleozoic to Mesozoic that most important consist Mobarak , Elika and Shemshak formations. Two bauxite horizons occur in this area: The “A horizon(middle Permian )lies between Mobarak and Elika formations,and “B”horizon(Upper Triassic)lies between Elika and Shemshak formations .The “B” horizon is minable and Geological studies and Explorations is do by APPI and Iran Alumina Co. In current time excavation is doing and minable ore is 11 million? ton.
Bauxite textures were studied in thin sections and Ooidic? , Pisoidic , Microclastic , Arenitic? and Conglomerate textures were determined . Ooids and Pisoids were surrounded by clastic matrix suggesting transportation erosion?? . Presence of compaction glee cracks in Pisoids indicate that they are first autogenically , and then were transported to the sedimentary basin .therefore it may be concluded that Jajarm karst? bauxite is the result of transportation and erosion of latritic bauxite.
In Cr , Zr ,Ga? diagram the Jajarm bauxite demonstrates that the parent rock of this bauxite is a mafic rock. Applications of “trace element accumulation coefficient “? and Cr content of samples in a logarithmic binary diagram also indicate mafic composition parent rock.
Subject List : Bauxite, ore deposite, Geochemistry