The book “Nannofossil stratigraphy and global events in the Paleocene and lower Eocene of northern Bulgaria” authored by Kristalina Stoykova, was out of print in English (July 2022). The book is published by the Academic Publishing House "Prof. Marin Drinov" of BAS (ISBN 978-619-245-125-7) and is financed by the Ministry of Education and Culture under the National Scientific Program "Protection of the Environment and Reduction of the Risk of Adverse Phenomena and Natural Disasters", approved by Decision of the Ministry of Education No. 577/17.08.2018.
The book presents a modern summary of the stratigraphy and global events in Paleocene-Eocene time, established on the territory of northern Bulgaria. The complex regional-stratigraphic study is based on 55 geological sections and hundreds of outcrops. 31 lithostratigraphic units dated by nannofossil biostratigraphy are described. New concepts for the spatio-temporal relationships of lithobodies were developed, a number of problems were clarified and the presence of the Selandian Stage in Bulgaria was proved. A complete zonation of the Paleocene and Lower Eocene by nannofossils was made, and 14 biozones and 51 bioevents were characterized in details. The following global events are studied: the Cretaceous–Tertiary boundary event, the mid-Paleocene biotic event, and the Paleocene–Eocene thermal maximum.