Abstract: In the Işıklar - Altındağ area (south of Bornova), the rocks of Upper Cretaceous age are representedmainly by limestones and divided from base to top, in the following units :

(1) Forominiferal - rudistid packstone of Late Turonian - Santonian age reflecting shelf lagoonal environment,

(2) Pelagic foraminiferal wackestone of Late Santonian - Early Campanina age indicating conditions of basinal facies,

(3) Bioclastic packstone of Late Campanian - Early Maastrichtian marking foreslope facies,

(4) Foraminiferal - algal packstone of Late Maastrichtian age was deposition in shallow shelf facies conditions.The Upper Cretaceous limestones are vertical and overturned towards northwest in the southeastern part of thestudy area and it always has a faulted contact with detrital rocks including local calcareous shale layers having fossilscharacteristics of Danian.The sea level changes which controlled the depositional environments of the Upper Cretaceous lithofacies unitsindicate a transgression reaching its peak during the Late Santonian and Early Campanian and accompanied by aregression lasting until the end of Late Maastrichtian.