Magnetostratigraphy of the Upper Berriasian “Zavodskaya Balka” section (East Crimea, Feodosiya

The results of magnetostratigraphic investigations in the Upper Berriasian Zavodskaya Balka section (Feodosiya, Crimea) are presented: magnetic polarity information, data on magnetic susceptibility, its anisotropy (АМS), frequency dependence (FD-factor) and other petromagnetic parameters. The analysis of the thermomagnetic and magnetic saturation curves has proved the presence of magnetite, being the main carrier of the remanent magnetization. Magnetic cleaning with alternating field and with temperature mostly has revealed the two-component composition of the magnetization, and the magnetostratigraphy is based on the directions of the most stable of them, with unblocking field from 35–50 mT and temperature from 300 to 540°C. The palaeomagnetic column presented specifies four heteropolar magnetozones – analogous to the M16 and M15 magnetic chrons (full M16n and M15r, parts of M16r and M15n). The existence of the M16n.1r subchron (“Feodosiya”) is substantiated, and it should be included into the Geomagnetic Polarity Time Scale. By bio- and magnetostratigraphic correlation, the section studied is an age analogue of the Paramimounum, Picteti and Alpillensis (probably Otopeta) subzones of the Boissieri Zone. The calculated sedimentation rate varied from 26.6 to 29.5 m/My.