AGE DATING OF PALEOGENE DIATOM DATUMS FROM THE MARINE CENOZOIC STRATIGRAPHIC KEY SECTION OF WEST KAMCHATKA AT THE KVACHINA BAY BASED ON MAGNETOSTRATIGRAPHIC DATA
A.Yu. Gladenkov1, A.Yu. Kazansky1
1 Geological Institute of Russian Academy of Sciences, Moscow, Russia
Keywords: Oligocene, diatoms, West Kamchatka, magnetostratigraphy, age of diatom datum levels
Abstract
Results on the age estimates of the Paleogene diatom datums derived from the magnetostratigraphy at marine Cenozoic stratigraphic section of the Kvachina Bay, West Kamchatka, are presented. Based on a direct correlation with the Geomagnetic Polarity Scale, it was possible to determine the age of such levels between Subchron C13r (35.10 - 33.73 Ma) and Subchron C9r (27.86 – 27.44 Ma). Of greatest interest are the age dating of the first and last occurrences of Lisitzinia ornata (27.71 Ma and 27.54 Ma respectively), and the first occurrence of Rocella gelida (27.49 Ma). This is the first experience of absolute age estimates of Oligocene diatom biohorizons based on magnetostratigraphy not only in Kamchatka sections, but in the North Pacific region in general. The obtained age estimates of diatom datum levels are compared with the published estimates from the literature on deep-sea cores in various regions of the World Ocean.
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