Sedimentology and stratigraphy of Türbeyanı marl sequences and İnpiri limestones (late barremian-albian): Implications for possible source and reservoir rocks (NW Turkey)

Thesis Type: Postgraduate

Institution Of The Thesis: Orta Doğu Teknik Üniversitesi, Faculty of Engineering, Department of Geological Engineering, Turkey

Approval Date: 2007




Sedimentology, cyclostratigraphy and sequence stratigraphy of the Türbeyanı Marls (Albian) and the İnpiri Limestone (Upper Barremian-Albian) members of Ulus Formation (İnciğez, Bartın, Amasra) were interpreted in this study. In the Türbeyanı Marls total of five different facies were defined. Marl and limestone facies are the most abundant in the succession. The depositional environment of the succession was defined as an outer shelf area. Within the pelagic marls 39 smaller order and 9 higher order cycles were recognized. These cycles correspond to the parasequences and parasequence sets of sequence stratigraphy, respectively. In the measured section only one type-3 sequence boundary was identified. In the İnpiri Limestones great variety of limestone facies are represented. Bioclastic, peloidal, intraclastic wackestone-packstone-grainstone facies are the most abundant. Moreover, occurrence of lime mudstone, fenestral limestone, ooid packstone-grainstone, and sandstone facies are present as well. In the measured section of the İnpiri Limestones 25 fifth order and 6 fourth order cycles were defined. These cycles correspond to the parasequence sets and systems tracts of the sequence stratigraphy, respectively. Total of three transgressive and three highstand systems tract were defined. Only one type 2 sequence boundary was identified in the measured section, the rest of them are interrupted by covers. This study revealed that the Türbeyanı Marls and the İnpiri Limestones are not economically valuable as petroleum source and reservoir rocks, respectively. The total organic carbon (TOC) values of marl facies of the Türbeyanı marls are very low, and the pore spaces observed in the İnpiri Limestone are cement filled making it unsuitable reservoir rock. Keywords: sedimentology, cyclostratigraphy, sequence stratigraphy, Türbeyanı Marls, İnpiri Limestones, Albian, Upper Barremian, Amasra, Bartın.