Annual Report 2011 of the Working Group on Paleogene Stratigraphy of the North Pacific

1. In April 2011 a workshop on Paleogene stratigraphy of the Sakhalin, Kamchatka and Japan region was held in Saint-Petersburg. Special attention was attracted to absolutely new data on Ypresian foraminifers and mollusks (sharp appearance of abundant warm-water assemblages in North Kamchatka) and diatoms (first finds in the Middle Eocene deposits of Kamchatka).
2. In August 2011 the Working Group met in Yuzhno-Sakhalinsk to discuss correlations of Paleogene stratigraphic charts for different regions of the Northwestern Pacific.
3. A large summarization “Discovery of marine Ypresian in North Kamchatka (stratigraphy, paleontology, and paleogeography)” has been completed and prepared for press. It contains stratigraphic analysis of assemblages of planktonic and benthic foraminirs and mollusks. Some zones and beds with fauna were distinguished. The Paleogene correlations between Kamchatka and North America revealed a large similarity (up to 50-70% common forms), which evidences for wide connections of shelf basins at this time. The biotic compositions suggest that the Ypresian period in the North Pacific was characterized by paratropical climate.

Report by Yu. B. Gladenkov, Chairman


Annual Report 2010 of the Working Group on Paleogene Stratigraphy of the North Pacific

A working meeting on Paleogene stratigraphy was held in Sakhalin, August 2010. It considered a new model of the Paleogene correlation scheme for the shelf basins of Japan and the Sakhalin-Kamchatka region. Special attention was given to the Early-Middle Eocene geological events: the greatest Cenozoic climatic optimum of Early Eocene and the tectonic and paleogeographic changes in the intial Middle Eocene). Investigations of the North Kamchatka Paleogene sequences continued. Abundant assemblages of mollusks (7 local zones with over 70 species), planktonic and benthic foraminifers (5-7 zones) of Thanetian and Ypresian have been distinguished for the first time. A monographic description and plates of this paleontological material are prepared. Analysis of the material shows that the Kamchatka assemblages are very similar to those from the Kalifornia formations. A nomograph on problems of the Upper Paleocene—Lower Eocene transitional beds is planned to be published next year. In parallel, paleomagnetic investigations of the same sequences have been carried out.

Report by Yu. B. Gladenkov, Chairman

Annual Report 2009 of the Working Group on Paleogene Stratigraphy of the North Pacific

A meeting on the Sakhalin-Kamchatka Paleogene was held in Moscow, April 2009, to consider new materials and to outline plans of works for 2010-2011. The works include particularly a part of a special project on geological evolution of the North Pacific shelf zones during the Cenozoic (biotic changes, sedimentational features, tectono-magmatic activity, paleogeographic rearrangements, climatic fluctuations, etc). Now it is very important to combine bio-, sequence-, seismostratigraphic investigations. We began to study new material on diatom flora from the Eocene of Kamchatka. The study of planktonic and benthic foraminifers and mollusks from the Cretaceous/Paleogene boundary beds of Sakhalin has been completed. Planktonic foraminifers were found there for the first time. A special paper "New Data on Maastrichtian-Paleogene Foraminifers from Sinegorsk Horizon of Southern Sakhalin" was published  in "Stratigraphy. Geol. Correlation", 2009, Vol. 17, No. 4, pp. 443-453. A monographic treatment of Paleocene and Ypresian of Kamchatka is continued. The Thanetian-Ypresian fauna (mollusks and foraminifers) reflecting the known climatic optimum is unique for these latitudes. The study of planktonic and benthic foraminifers from the Cretaceous/Paleogene boundary beds of Sakhalin has been completed. Planktonic foraminifers were found there for the first time. A special publication is under preparation. A monographic treatment of Paleocene and Ypresian of Kamchatka is continued. The Ypresian fauna reflecting the known climatic optimum is unique for these latitudes.

Report by Yu. B. Gladenkov, Chairman


Annual Report 2008 of the Working Group on Paleogene Stratigraphy of the North Pacific

A meeting on the Sakhalin-Kamchatka Paleogene was held in Moscow, March 2008 to consider new materials and to outline plans of works for 2009-2010. The works include, particularly, a special project on geological evolution of the North Pacific shelf zones during the Paleogene (biotic changes, sedimentational features, tectono-magmatic activity, paleogeographic rearrangements, climatic fluctuations, etc.).
Some publications on the North Pacific Paleogene have been prepared as contributions to the proceedings of the 9th International Congress on Pacific Cenozoic Stratigraphy (Tsukuba, Japan, October 2007). The Congress was attended by specialists from Japan, USA, Russia and other countries (K. Ogasawara, A. Oleinik, A. Gladenkov and others). The discussions dealt particularly with problems of Paleogene correlations between subtropical and boreal regions. A special attention was paid to paleobiogeographic reconstructions.
At the time of the 33 IGC (Oslo, Norway, August 2008) the Seminar “Oligocene Series: A time of change in Earth and life history” (conveners N. Vandenberghe, Yu. Gladenkov) was held. The Seminar raised a great interest: 20 presentations discussed different Oligocene problems including stage and zonal subdivision, elaboration of regional refined schemes, reconstruction of paleogeographic and paleoclimatic events.
The study of planktonic and benthic foraminifers from the Cretaceous/Paleogene boundary beds of Sakhalin has been completed. Planktonic foraminifers were found there for the first time. A special publication is under preparation.
A monographic treatment of Paleocene and Ipresian of Kamchatka is continued. The Ipresian fauna reflecting the known climatic optimum is unique for these latitudes.

Report by Yu. B. Gladenkov, Chairman


Annual Report 2007 of the Working Group on Paleogene Stratigraphy of the North Pacific

1. A meeting of the Working Group of Paleogene Stratigraphy for the North Pacific was held in Moscow in March 2007.
It discussed new data on the region (several presentations were made) and outlined plans of activities for 2008-2010.
2. The 9th Congress on Pacific Neogene Stratigraphy was held in Tsukuba (Japan) in October 2007 (leader Prof. K. Ogasawara).
During the Congress some problems of Paleogene stratigraphy were especially discussed.
Among them were correlations of oceanic and shelf areas and environmental changes (J. Barron, A. Gladenkov, E. Suparka, K. Ogasawara, and others).
3. A field excursion was organized to the Pacific coast of NE Japan (Sendai and Hirono, Joban areas). It included examination of Oligocene formations.
4. In 2007 a new Russian project 2008-2010 was set up to study geological evolution of North Pacific shelf zones in the Cenozoic (particularly, in the Paleogene) . The project embraces investigations of biotic assemblages evolution, sedimentational, tectonic,
magmatic, paleoclimatic and paleogeographic processes. The project will result in
Paleogene refined stratigraphic schemes andcorrelation of geological events.
5. Field investigations of the transitional Paleogene-Cretaceous beds were carried out in Sakhalin. Planktonic assemblages of this interval have been first recovered there (V. Beniamovsky and others).
6. Works on the Ypresian sequences of Kamchatka, which included studies of molluscan and foraminiferal assemblages, were continued (V. Sinelnikova). Studies of this previously unknown rich fauna will provide better knowledge of the climatic optimum in
boreal latitudes.
7. A significant summarization on Paleogene volcanism of the Kamchatka region has been accomplished (A. Shantser). As a result, certain phases of volcanic activities were established in the Paleogene (about 40 mln y.) on the base of changes of volcanism areas and composition of volcanic rocks.
8. Comparative studies of the North Pacific Eocene and Oligocene biotas were conducted (Yu. Gladenkov). Analyses of areas of distribution of shelf and oceanic assemblages and environmental changes were made.
9. A volume "Late Cenozoic detailed stratigraphy and marine ecosystems of the North Pacific region based on diatoms (Moscow, GEOS, 2007, 288 p.) was published (A. Gladenkov).
10. The symposium "Oligocene Series: A time of change in Earth and life history" was included into the program of the 33rd IGC in Oslo (N. Vandenberghe, Yu. Gladenkov).
All these items were reflected in related publications and presentations.

Report by Yu. B. Gladenkov, Chairman

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



Annual Report 2005 of the Working Group on Paleogene Stratigraphy of the North Pacific

In summer 2005 the Working Group on North Pacific Paleogene conducted fieldworks in Sakhalin to study
a) Cretaceous-Paleogene transitional beds and b) marine Oligocene sequences.
We collected extensive paleontological and litological material for future investigations.
A large collective monograph describing stratigraphy, paleontology, geological events, paleobiogeography, paleoclimatology of the North Pacific Oligocene is to be published in late 2005 in the series "Biosphere-ecosystem-biota in the Earth past." The series is devoted to the centenary of Prof. V.V. Menner, former President of ICS and ISPS.
3. A working meeting on North Pacific Paleogene problems was held in In August 2005 in Sakhalin. The meeting outlined a plan of activities for 2006-2007.

Report by Yu. I. Gladenkov, Chairman.

Report on activities of the WG on North Pacific Paleogene in 2003-2004:

1. A field work was organizied to enable Russian and Japanese geologists (paleontologists and lithologists) to examine the key Paleogene sections of northeastern Kamchatka and North Japan (Hokkaido). The sections were sampled for microfaunal (foraminifers and diatoms) analyses. The samples are under study now. Macrofaunal samples (mollusks) have been also collected. A comparative study of the Paleogene sections of different climatic belts may form a base for reliable correlation of these sections and subtropical and tropical biotic assemblages of the North Pacific.

2. Special investigations have been initiated to study Oligocene deposits of the North Pacific surrounding structures. The studies include thorough analysis of sections from Japan (in the south) to Chukotka (in the north) and from Alaska (in the north) to California (in the south). About 15 specialists are involved. Comprehansive investigations have been carried out in two Oligocene sections of West Kamchatka, where some horizons, zones and beds were outlined for the first time and a new model for their correlation to other North Pacific sections was worked out. Special significance is attatched to monographic description of Oligocene marine fauna and flora to be completed in the next years. By the present, more than 100 molluscan species, about 20 species of leaf flora, and over 35 species of foraminifers have been described.

A series of paleobiogeographic maps are planned to be compiled in the next years to show areas of distribution and migrations of the North Pacific biotic assemblages during the Oligocene time. The Oligocene stratigraphy of the region will be consiodered in several articles and a special monograph.

Report by Yu. I. Gladenkov, Chairman.