Volcanology and petrogenesis of Hezar volcanic complex in south west of Rayen (Kerman province)

The studied area is a part of Hezar volcanic complex (in Urmieh-Dokhtar volcanic belt) that situated in the southwest of Kerman. This complex represents last volcanic phase of Eocene in Kerman and consists of alternation of lava flows, pyroclastic deposits and volcanoclastic sediments. Lava flows contain basaltic andesite and olivine-basaltic andesite. Lithologically, pyroclastic deposits contain volcanic breccias and volcanogenic sandstones and sedimentary rocks such as limestone, siltstone and sandstone. According to the geochemical studies, the lava flows are andesite to basalt and calcalkaline in composition. In genetic classification, pyroclastic deposits belong to the pyroclastic flow deposits (pumice and lithic flow, ash flow tuff, and base surge flows) and fall deposits. Facies analysis and volcanological studies in the upper part of this complex show that these deposits have been produced by numerous explosive plinian eruptions in stratovolcanoe(s). In some cases, each of these eruption phases, have been produced extensive volume of pyroclastic deposits and lava flows. The products of these phases have changed gradually, and some times there are short periods without volcanic activity between them. In these periods, primary lithologies have weathered and eroded, and volcaniclastic deposits have been formed. It is probable that the eruptions have been occurred in aerial environments and parts of products have deposited in the local lackes. In the calm periods, these lakes are suitable situations for deposition of limestones. The facial and textural evidences indicate the studied area is probably located in medial to distal facies of Eocene composite volcanic cone(s).