NEOGENE STRATIGRAPHY OF THE NORTHERN PART OF KARABURUN PENINSULA

The terrigenous Neogene lithology in north of Karaburun peninsula is represented by Lower- Middle Miocene rock units which are cut and bounded by NW-SE trending synthetic faults. Dominant lacustrine sedimentation (Haseki and Hisarcık formations) of Early-Middle Miocene period which was separated by upper and lower regional unconformities, and the Early Miocene mafic volcanism (Karaburun volcanites) were studied within the scope of Karaburun group. Haseki formation which reflects Early Miocene sedimentation begins with fills of alluvial fan of the Salman member and is basically formed by algal-biostromal Yeniliman limestone and lacustrine deposits of Aktepe member. With synsedimentary emplacement of the 1st phase Karaburun volcanites over Yeniliman limestone platform, the dominant sequence which is micritic limestone intercalating with diatomite of the Aktepe member was deposited in environmental conditions deepening towards shore-face. The effectiveness of NW trending boundary faults which gave rise to 2nd phase of the Karaburun volcanism, shaping the western edge of Foça depression towards the end of Early Miocene has not changed the dominant depositional environment, and lacustrine sedimentation has continued with Hisarcık formation. Green and fine clastic shore-face sediments (Karabağları member) of the Hisarcık formation which deposited the latest between Early Miocene-Middle Miocene overlie Aktepe sequence with submarine parallel unconformity. Karaburun volcanism which is represented by high potassium andesitic products with calc alkaline character (pyroclastics and olivine- phyric lavas) is synchronous with sedimentation of Haseki formation and has two phases. Pyroclastic rocks which are in facies of base-surge, air-fall and ash-fall in lesser amount were emplaced before lava eruptions. K/Ar aged, 1stphase products, which are 18.2±1.0 my according to K/Ar dating, are in the position of stratigraphical reference level which separates Yeniliman limestone from Aktepe member. Second phase products are emplaced in Aktepe sequence.