Jeoloji Mühendisliği Dergisi

ABSTRACT: The Attepe Iron Deposit takes place in the Precambrian age Emirgazi Formation which belongs to Geyik Da Unit of Taurus Tectonic Belt. The iron deposit consists of pyrites, siderites and hematites from bottom to top, all are formed in the sedimentary conditions. The deposit crops out by the effect of faults after the mineralization. At that stage, especially siderites and other iron minerals were turned in to limonite and goethite due to karstification and surficial processes. The iron rich zones formed by this way provide raw materials for the operation. The present position of ore and host rocks is tectonically related. The processes related to diagenesis, metamorphic and late phase deformations caused strong folding and faulting tectonism of the area. The metals dissolved from primary iron minerals of sedimentary origin are mobilized to fracture zones which led to late stage siderite vein and veinlets. In the siderite samples, siderite, ankerite, pyrite, rutile and mangane dendirites have been dominantly determined. In addition, very little amount of shortite minerals accompany to the above association. Siderites consist of % 55,1-65,3 Fe203 (total iron), 2,2-10,0% SiO2, 0,9-1,3% MnO, 0,03-1,7% Al2O3, 2,1-3,6% MnO; On the other hand, limonite and goethite contain 57,2-93,8% Fe2O3 (Total iron), 0,5-1,6% MnO, 1,1-3,6% SiO2, 0,1-0,6% Al2O3, 0,05-0,6% MnO. The Cr2O3 content of 140 ppm determined in metasiltstones is also noticable. Due to evaluations of chemical data of the samples, a tendency toward relationship to basic rocks can be postulated about the origin of iron of primary sedimentary iron formations. On the formation of Attepe Iron Deposits, it has supposed to be a tendency to a probable volcanic - syn-sedimentary type, when the interpretations of the study area with all other investigations. Within the frame of this study, it is highly recommended that Precambrian units must be investigated in detail during further studies.

ABSTRACT: One of the most important mining activity areas of the ancient Anatolian civilizations is Lake VanBasin. Urartians, capitalized around City of Van, has tremendous metal produced and famous Urartianceramics for centuries. Moreover, their mastery in metal production gives the name of the Bronze Age, oneof the antic epoch of Anatolian civilizations. Considering this historical background, it is clear that metaland industrial raw material production took place in the basin for couple of thousands of years, which theycan also be accepted as environmental contaminants for Lake Van. The final drainage of the rivers of LakeVan Basin is the Lake Van itself. Thus, all pollutants derived from economic activities in the basin weredrained to the lake and the geochemical composition of the lake has changed according to the amount ofthe anion-cation-heavy metal composition of drained waste waters. This study focuses on geologicalenvironment and contaminations derived from urban areas and agricultural activities are out of interest.This study aims to demonstrate the environmental impact of the mining activities, quarries, non-minedmineralization areas, natural radioactive contaminations and geothermal discharges in the basin. Thespecial geochemical composition of the Lake Van started to change after urbanization around the lake andun-controlled industrial activities; the long-term geochemical effects of the geological composition of thebasin will be discussing in this paper with the exception of the environmental impact of the humanitariancontaminants.After this study, the mineral location map of the basin was updated and the environmental impacts ofmining works and natural geological contaminants on the Lake Van have been evaluated. Remote sensingtechniques were used to locate the mineralization and alteration zones and dip maps were prepared toevaluate the erosion effect onto these sites. The relation between radioactive anomalies described inprevious studies and geology have been examined. As a consequence, the mining works such as gravelsand production, pumice and other quarries and mines are precipitating the erosion of the basin.Afterwards, both chemical contamination and sedimentation rate were increased. As a result, NaturalHabitat of Lake Van is getting polluted day after day because of these uncontrolled mining works andgeological - geomorphological behavior of the Lake Van Basin. As a solution, comprehensive geochemicalstudies shoul be undertaken immediately in tha Basin including all pollutants derived both fromcivilization works and the nature fo the geological environment. These studies should be used to constructthe sustainable environmental management system of the Lake Van Basin.