Foraminiferal content and biostratigraphy of the mesozoic carbonate sequences in the vicinity of Gümüldür and Menderes (İzmir- Western Turkey)

The Mesozoic carbonate successions, cropping out around Menderes and Gümüldür, are represented by neritic limestones, dolomitic limestones and dolostones of different blocks or slices of Bornova Flysch Zone. Limestone and dolomitic limestone parts of sections consist of biomicritic, biosparitic limestones and Thaumatoporella-bearing biolitites. Some blocks comprise Upper Triassic to Lower Jurassic carbonates and some others include only Lower Jurassic limestones. Triassic parts of these carbonate sequences include a foraminiferal fauna consisting of Aulotortus gr. sinuosus, Aulotortus sp., Reophax sp., Trochammina sp., Textularia sp., Endotriada sp., Ophthalmidium sp., which allow us to use a Late Triassic age. Jurassic parts of sections, on the other hand, have a foraminiferal fauna and algal flora consisting of Siphovalvulina cf. gibralterensis, Lituosepta sp., Duotaxis metula, Meandrovoluta asiagoensis, Duotaxis sp., Trocholina sp., Endotriadella sp., Pseudocyclammina sp., Orbitopsella praecursor, Agerina cf. martana, Plaeodasyladus mediterraneous, Taumatoporella parvovesiculifera and indicating a Liassic age. Liassic carbonates show a transition from neritic facies to deep sea facies in Değirmendere I and Değirmendere II type sections and contain Late Cretaceous neptunian dykes. This may reflect that the collapse during the Liasic is a sudden and large collapse.