Abstract: The aim of this study is to demonstrate the basic geological characteristics of the region where thePontides and the Taurides are the closest to one another, and to interpret the structural evolution.Four major units of pre-Eocene age have been recognized in the study area. They are tectonically related toone another and reflect different environments. These units from north to south, are the Kelkit Autochthon, theÇimen Dağı Nappe, The Erzincan Nappe and the Munzur Limestone.The base of the Kelkit Autochthon consists of the greenschists and an intrusive Gümüşhane Granite. TheLiassic detritics transgressively cover the basement rocks. The Liassic rocks grade in the Upper Jurassic-LowerCretaceous platform carbonates. This part of the autochthon represents a stable continental margin. The Jurassic -Lower Cretaceous rocks are overlain with an an angular unconformity by the Upper Cretaceous-Paleocene volcano -sedimentary rocks.The lowermost part of the Çimen Dağı Nappe consists of the Tokat Metamorphites and partly of the Carboniferous-Permian volcanosedimentary rocks. A heterogenous rock assemblage of Jurassic-Lower Cretaceous age coversthe basement rocks with an angular unconformity and represents continental shelf deposits. The Erzincan Napperepresents the Upper Cretaceous-Paleocene subduction complex and its products.