Lithological and Geochemical Characteristics of the Paleocene/Eocene Sediments corresponding to the PETM Biospheric Event in the Eastern Crimea (Nasypnoe Section)

Abstract

The paper reports lithological and geochemical data on the stratigraphic interval corresponding to the Paleocene/Eocene Thermal Maximum (PETM) event in the Paleogene section of Eastern Crimea (Nasypnoe section). The section is located on the western continuation of the sublatitudinal profile consisting of 15 PETM sections spanning the area from Crimea to Tajikistan (over 2500 km). It is shown that PETM sediments have the negative δ13C and δ18O isotope excursions and are enriched in kaolinite, which is typical of most sections of this interval around the world. At the same time, the extremely low content of organic matter (OM) in sediments of the Nasypnoe section makes them sharply different from the highly carbonaceous rocks of the PETM interval in Central and Eastern Caucasus, and Central Asian regions. This is correlated with the low contents of many chemical elements in the studied rocks, and their extremely high contents in the highly carbonaceous rocks of the easterly sections. Thus, Eastern Crimea in the end of the Paleocene‒beginning of the Eocene was occupied by the low-bioproductive marine paleobasin, whereas the coeval paleobasin in Central Asia was characterized by extremely high bioproductivity owing to the presence of significant amount of phosphorus.