Basic Study on Hemispheric Climatic Changes and on Transition of Paleoenvironments in Huge Tectonic Lakes.

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1. PROGRAM CARRIED OUTIn our joint work on the present theme, we had concentrated our study to South Africa and lake Baikal ; the most distinguished features as tectonic lake are observed in both typical tectonic lakes such as Tanganyika and Baikal. As the first step to study Lake Tanganyika, we started stratigraphic study on the core sample obtained in Verloren Vlei because Lakes Tanganyika and Malauii is regarded as one unit of African tectonism extending to southern coast.On the other hand, paleolimnological study is carried out in Lake Paikal by Russian and American joint work supported also by Japanese and Netherlanders. And we obtained tentative example of 4.61m long core in order to compare the succesion of lake type between Biwa and Baikal. We already obtained very valuable data. These academic data are printed in IPPCCE News Letter.As the result of these two ancient lake sediments, we could obtain clue to study two distinguished tectonism in the world.2. RESULTIn South Africa, … More we obtained 50m long core and pollen analytical work was done by Dr. Meadow and granurometric work was carried out by people under auspice of Prof. Parkington, University of Cape Town. On the other hand, we obtained core sample of 300, 000 years old at Lake Saltpan in which pollen analytical work was carried out by Dr. Sara Kerr under the guidance of Profs. Scott and Partridge. Althouth it is still difficult to clarify the whole climatic succession, it is clear that South Africa had been suffered by cold climate during the correlating age with the Northern Hemisphere in the Pleistocene. For result on geomagnetic feature, it is unfortunately not successful for the reason of lot of non-magnetic minerals existence (below 3 x 10^<-7> emu/cm^3).In the case of Baikal, 4.61m core had verified the existence of two units of environments. In this regard, Pleistocene-Holocene boundary seems to be 1.5 meters deep level. Probably the sedimentation rate might have been 0.01mm at the 700m deep spot in the northern basin. Above that 1.5m level, plenty of planktonic diatom fossils were found on the contrast to poor amount of diatom fossils below that level. Above that 1.5m is regarded as Holocene warm climate deposit. That age might cause high productivity. It is similar with the case of Lake Biwa sediments. Regarding pollen grains, we can find out colder climate substage below 1.5m level denoting Wurm climate fluctuation. From the view-point of organic chemistry, terrestrial production as forest coincides with the autochthonous variation of lake organism such as planktonic diatom and also zooplankton composition. It is also comparable with Lake Biwa history supporting the possibility of establishing chronology in the Northern Hemisphere by both Lakes biwa and Baikal. Less