The Provenance of the Varzaneh Aeolian Sand Field Regarding to Lithology and Texture, SW Esfahan, Iran

Abstract

The main mineralogical/lithological composition of the Varzaneh aeolian sands is sedimentary and igneous lithics. The minor one is metamorphic lithics and mineral grains (such as quartz, feldspar and heavy mineral grains) respectively. The origin of the sedimentary lithics (mainly carbonates) mostly is from sedimentary rocks exposed in the west and the southwest of the study area. These rocks belong to Cretaceous and Jurassic outcrops. The origin of the igneous lithic grains chiefly belongs to Tertiary highlands, located to the north and the northeast of the study area. The main origin of the metamorphic lithic grains is from the mountain ranges located in the north-western and the western part of the drainage basin of the Zayandeh river. Texture of the aeolian sand grains is similar to the Zayandeh river sediments. Concentration of the aeolian sands at the west of the Zayandeh river delta, variation of their mineralogical/lithological composition from north to south, and textural characterizations of sand grains indicate that the water laid sediments of the Zayandeh river, widespread to the north of the aeolian sands, are the main supply of the aeolian sands and sediments deposited by the two ephemeral streams in the south and the southwest of the sand dunes are minor one.