The petrographic and geochemical features of the volcanic rocks that outcropping in the yolçati village around and usability as a concrete aggregate

Study area, in eastern Anatolian region, in about 22 km northwest of Bingöl state, notably Yolçatı village that situate on the way to Elazığ-Bingöl, Sarıcan, Görmezler, Bulgurcuk, Kuruca, Dikme, Gökçekanat villages and with these villages around, is limited. In study area, Middle Eocene-Upper Oligocene Kırkgeçit Formation with together study subject Upper Miocene-Pliocene Solhan Formation outcrop. Solhan Formation usually pyroclastic rocks that occur from tuff and pyroclastic brecia and lava flows is represented. In this study, petrographical and geochemical characteristics of lava flows is investigated. In the area, lava flows that is dark colour, locally cooling crack, bedding, round the big blocks show different physical and morphological features according to rock types. Especially, while basaltic lavas are characteristic by round the big block, fine crystalline, extreme rigid and sharp-edged, other rock types have characteristics such as very fragile, fissured, porphyritic and vesicular texture. As a result of petrographical study of lava flows of Solhan volcanites, it is determined that rocks are basalt, andesite and trachyte composition. Rocks usually demonstrate porphyritic, glomeraporphyritic, ophitic, sub-ophitic, vesicular and trachytic textures and consist of plagioclase, olivine, pyroxene, sanidine phenocrystal and rate of phenocrystal index is 35%. Generally, in the rocks, opaque minerals are common, and Ti-magnetite in composition. In balance textures that indicate assimilation, magma mixing, fractionation are commonly seen in these rock. According to whole rock analyse datasets, it is seen that rocks are separted into two different groups alkaline and sub-alkaline. It is thought that, these rocks that show usually same characteristic in element distribution are different source region, but occur from same fractionation process. Sim Toprak and Şakşak quarry samples are analyzed as aggregate characteristics, and it is determined that, their specific gravity and frost resistance are suitable as aggregate material, however in terms of alkali reduction and solute silica values of these samples availability are not convenient. Key Words; Solhan volcanites, Petrography, Geochemistry, Magma Mixing, Differentiation, Aggregate