ABSTRACT: Mı© study area lies within the Ankara, Elmadağ- and Kalecik region, Central Anatolia. In this region, the Lower Triassic to Quteraary aged litho— imitas outcrop. The Emir Formation is the oldest authcchthoiLOUs müt ini the region. It is affected by the metainiorphtsm of green-schist fades, and contains metaperidotites, These »re also effected by the same luet&mo^phfem ,The Emir Formation grades upward»  in to the Mmadaf Formation, This formation Is also a metaeiwphle unit In the green-schist fades, and is inter, calated with the coeval volcanic unit, namely the OrtakÖy Formatton, The Ortalcöy Formatton mataiy contains of volcanites it preserved pîMow structures, and radiolarites and limestones. The Etoiadaf Formation grades upwards In to the Keçikaya Formation consisting of sandy Hmeston© and limestone. All these unite have been named the Ankara Group, and are cut by diabase dikes. The Ankara Group is of Triassic age» and atoo contains variously sized blocks composed of the Carboniferous and Permian elastics and limestones througlïDut the area* The Lia£§ıe Hasanoğlan formation unconf ormably overlies the Ankara Group witii a basal conglomerate, and consists of a sandstoneanuidstone-llmestone alternatwDn, Upwards, it grades In to the clayey Ume&tone. The Eldlvan Opbiolite Complex shows the characteristics of a regular ophlolite sequence, however fin the »tudy area the uppermost levels are not observed. After the emplacement »of the K Uli van Oph&olite Complex^ the depth of th© äepositional basin gradually increased. In tMs basin, the Hisarköy FOPnmtïôii oonslMng of sandstone, volcareiilto, conglomerate and vulcanic», formed together with the Karadağ Forinutijoii the latest showing the charecteris tics of a normal flysch. These units toterflnger laterally. Both formations contain variously sized olistol`fchs and oO«thostrome§ derlvea from Liu FJdivim Ophio lite Complex the Hîsarköy and Karadağ formations grade upward» faito the Ihcapitiar and Samanlık forma, turns of maestriehtianage. The Samanlık,Formation consists of interniediate turbiditesf and shows,a graded contact with the Paleocene BMİitaşlar Formation characterised by ttie proximal and intöritiediate turbidltBi, Huge limestone oltetoüths derived from the peneconteniporaneous reefs occur to the Dizilitaşlar FoiTnation, The Ätohmutlar Formation which is Eocene in age, and is c»Mnposed of conglomerates, sandstones, shales attd marls was deposited in toe shelf, deltaic, beach, coastal plato and alluvial fan environments. The Deliler Völcanite te of the same age witti ttie Mahmutlar Formation, The Oligocène Mlâkincedere Formation consists of conglomerate, mudatoiia, sandstone, marl and gypsium, deposited in tiie meandering river and evaporitlß lake environmente. The Late Mûcene-Fliocene Tekke Vulcanite laterally intercalates with the Karapınar» Kavaklı and Mamak Formatioiis. The Karapınar Formation WJIH depositnd in the alluvial fan environment, and consists of conglomerate, sandstone and tuff; ine Kavaklı Formation tonipored of clayey limestone, marl, daystone, öomgfomerate, sandstone and tuff was deposited in the fluvial and lacustrine environments; and the Mamak Formation is made up of agglomerate and tuff. The Bozdaf Basalt which is the last product of the volcanic activity in the region unconf ormably overlies all cf the «alder units. The Pliocene Gölbaşı Formatton is composed of uneonsolidated to poorly con lolidated cîasticn. and shows a considerable lateral extentkm. The tectumlc structure of the region resulted from the Alpine orogenesis, In the study area, there are a number of low angle upthrusts. Along these uptlirusts» it appears that the Ankara Group overlies the Upper Cretaceous and Oligocène units, the Upper Cretaceous-units overlie the Faleocene sediments, and the Paleo- •cene units overlie tihe Socene deposits. In the light of toe evidence resuittoi; from the field ob»erva#on§, a géotectoriic madel for Central Anatolian has been suggested.