Stratigraphy of the Bolu Massif (north of Bolu) and its close vicinity [Bolu Masifi (Bolu kuzeyi) ve yakin civarinin stratigrafisi]

Abstract

The study area covers the Bolu Massif and its surroundings which are located at the north of the Bolu. In the study area, thirteen units have been discriminated as Karadere metamorphites (Precambrian), Yellice formation (Cambrian-Ordovician), Dirgine Granitoidleri (Ordovician), Isigandere formation (Ordovician-Silurian), Kocadere formation (Silurian-Early Devonian), Haciyerdere formation (Middle Devonian), Hizardere formation (Late Cretaceous), Sarikaya formation (Late Cretaceous-Paleocene), Melendere formation (Early Eocene), Cukurca formation (Middle Eocene), Keltepe Volcanites (Neogene), Orencik formation (Plio-Quaternary), Quaternary alluvium (Quaternary). During Early Paleozoic, volcanic and granitic rocks have been placed in the area. Between Ordovician-Middle Devonian, the succession which occurred initialy as clastic and then carbonate sedimentation has been interrupted from Mid-Devonian to Late Cretaceous. During the time span between Cretaceous and Quaternary, the sedimentation of epiclastic and carbonate rocks has taken place accompanying with a volcanic activity.