Annual Report 2006 of the Working Group on Paleogene Stratigraphy of the North Pacific

In 2006 the activities of the Working Group of the North Pacific Paleogene were as follows:
1. Working meetings of Russian and Japanese specialists were held in November 2005 in Moscow, in March 2006 in Japan, and in July 2006 in Sakhalin to discuss some problems of the Paleogene stratigraphy.
2. Field works in Japan (the Honshu Island). The Russian-Japanese group guided by Prof. K. Ogasawara examined the Upper Paleogene sections (the Iwaki, Asaki, Shirasaki formations).
3. The joint group headed by Prof. Yu.B. Gladenkov examined the Paleocene-Oligocene sequences of W. Sakhalin (the Snezhinkinskaya, Krasnopol’evskaya, Takaradaiskaya, Arakaiskaya, and Kholmskaya suites).
Main goals of the 2006 works were to study paleontological content and lithological features of the sections, to elaborate correlation schemes, and to reconstruct geological events and
paleogeographic settings. Samples were collected for paleontological and lithological analyses and some of them especially for establishing biomarkers. It is of interest that a number of sections showed an increased concentration of isoprenoids at the Eocene-Oligocene boundary. This may reflect an increased productivity of diatom flora in the Early Oligocene.
In addition, a new version of polarity reversal scale was worked out for the Kamchatka Paleogene, which is correlatable with the Standard Scale. Much attention was paid to monographic description of fossils (130 species of mollusks, foraminifers, and flora were described from the reference sections of Kamchatka).
The results obtained were discussed in a number of publications. Papers summarizing paleobiogeographic data on shelf zones of the Late Paleogene (Eocene-Oligocene time) are of
special significance.
The works were supported by the Russian Foundation for Basic Research
(project leader Prof. Yu.B. Gladenkov) and the JSPS (leaders Prof. K. Ogasawara and Dr. A. Gladenkov).

Report by Yu. B. Gladenkov
Chairman of the Working Group of the North Pacific Paleogene