Facies, biostratigraphy and isotope chemostratigraphy of the Tithonian‒Berriasian transition in the easternmost Getic Carbonate Platform (Southern Carpathians, Romania)

Abstract

The easternmost side of the Getic Carbonate Platform at Postăvaru and Piatra Mare Massifs of Southern Carpathians (Romania) has been studied through eighteen sections using macro and microscopic analyses, micropaleontological studies combined with sedimentological and oxygen and carbon isotope analyses. The studied area is located in central Romania, in the easternmost part of the Southern Carpathians, in the vicinity of the Carpathian Bend. Eight major facies associations are identified defining lower slope, upper slope/reef crest, platform margin and inner platform depositional environments. The microfossil assemblages contain foraminifera, dasycladalean algae, microproblematica and calpionellids characterizing the Tithonian and Berriasian stages. The carbonate succession shares similar characteristics with coeval deposits from the Southern Carpathians and other regions of the Tethys Realm (especially Northern Calcareous Alps, Polish Outer Carpathians, Carpatho-Balkanides, Albanides and Hellenides). The sedimentological and isotope chemostratigraphic analyses provide evidence that subaerial exposure was common in shallow-water and inner platform depositional settings, in a prograding context, under the influence of carbonate sedimentation and eustasy. All the investigations allow deciphering the Tithonian–Berriasian transition in the easternmost Getic Carbonate Platform.