Investigation of geochemical features and heavy metal content of çoruh river (Bayburt) stream bed sedi̇ments

The subject of the thesis is composed of the river bed sediments of Çoruh River. In this contex, based on the geochemical characteristics of deposits is to obtain information about source areas providing material to the river, chemical weathering of source areas and heavy metal content and origins. Along the Çoruh River have made working in an area about 40 km. This distance is named BM ( between Bayburt centers and Gezköy, intensive residental), GK (between Gezköy and Gezhanları, sparse residental) and ZT (between Gezhanları and Ziyarettepe sırtı, rural) codes have been evaluated as three parts. There are positive correlations between Al2O3 and Na2O, K2O, TiO2, P2O5, CaO content of this samples. The SiO2, Al2O3, K2O, Na2O, TiO2, P2O5, MnO elements are generally depleted relative to Upper Continental Crust (UCC), the other main element are enriched. There are positive correlations between Al2O3 and Rb, Sr, Ba, Th, Hf, Y, Nb, Zr, V, Pb, U, Cu content of the investigated samples. When the trace element components of the samples are compored with UCC, Rb, Sr, Ba, Th, U, Zr, Hf, Y, Nb and Pb are generally depleted, Co, Ni, Cu, Sc and V are genarally enriched, Au is from time to time depleted and enriched. The ratios of (Gd/Yb)N are >1, (La/Yb)N are between 6.92 – 8.71 and Eu/Eu* are between 0.75 and 0.89. The light rare earth elements (LREE) and the heavy rare earth elements (HREE) showed positive correlation with Al2O3, K2O, TiO2, P2O5, Zr, Th, Y. There are minor enrichment of Zn, Sn and Sc contents of analyzed samples, minor–moderate enrichment of Cu, severe enrichment of As and extremely enrichment of Ni. Copper content of the stream bed sediments is partially geological, partially antropogenic, As is entirely antropogenic, Ni is fully geological origin. As a result, the stream bed sediments are derived from participle – mafic/ultramafic sources. Poor to moderate degrees of chemical weathering of this sediments indicates time to time increased tectonic activity, increased erosion and rapid sedimentation in semi arid-arid conditions in the sources region. Thus, the sediments are immature chemically. These sediments are exposed both lithogenic and antropogenic contamination.