Global warming is thought to be difficult to predict because of the complex system science involved. It is poorly understood how much affected is climate change by fluctuations of solar activity on X-ray and UV, though the recent increase of CO_2 in the atmosphere is undoubtedly one of the most important factors for global warming. Furthermore, there are many unknown factors related to climate change, such as increasing water vapor pressure linked to temperature increase, and feedback systems of cloud cover and albedo change. In this review I will discuss the present state of understanding of global warming on the basis of the historical geology in the following order; (1) the history of climate change in the Quaternary, (2) factors of bearing on climate change, such as greenhouse gases, saturated infrared absorption intensity, radiation forcing, fluctuation of the solar energy, and influences of volcanic eruptions, forest fire and continental yellow dusts, and (3) feedback mechanisms of dissolved CO_2 in the ocean, secular change of the albedo, and the relationship between cosmic radiation and total cloud cover. In conclusion, it is emphasized that natural climate change should be extracted from recent global warming, while simultaneously studying the positive feedback mechanism due to increasing greenhouse gases.

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The Goyosan pluton in the Kitakami Mountains belongs to Kitakami zone V by Katada (1974) and has been divided into 3 types, e.g. Yoshihama, Kuroiwa and Okuboyama types. I newly found gabbroic rocks and redefined the Okuboyama type by a geological survey of the Goyosan pluton. In contrast with the previous results, the Okuboyama type granite is distributed in E-W direction with nearly constant width. The Okuboyama type granite has a quench texture near contact to the Yoshihama type granite. This shows that Okuboyama type granite intruded into the Yoshihama type tranite. However, magnetic susceptibility increases from the Yoshihama type granite to Okuboyama type granite near the intrusion boundary the Okuboyama and the Yoshihama type granite. This observation suggests that the Yoshihama type granite did not completely solidificate at the time of the intrusion of the Okuboyama type granite. Although both the Yoshihama and the Okuboyama type granite are composed of granodiorite and tonalite, there are the differences in modal compositions, for instance, the Okuboyama type is richer in feldspar than the Yoshihama type. As corresponding to the differences in the modal compositions, the Okuboyama type is also characterized by high Na2O, Al2O3 and P2O5 concentrations, and low K2O, total Fe2O3 concentrations, in comparison with the Yoshihama type. Therefore, chemical trend of the mentioned above elements of the Okuboyama type on variation diagrams against SiO2 is different from these of the Yoshihama type. Furthermore, the rocks of Okuboyama type are characterized by high Sr content and low Rb, Zr, Y contents. These features are similar to those of the plutons in the Kitakami zone II, and suggest that the Okuboyama type can be recognized as high-Sr series (adakitic rocks) in the sense of Tsuchiya and Kanisawa (1994). A model based on slab melting may account for high Sr/Y ratio of adakitic rocks and closely distribution of adakitic rocks and non-adakitic rocks.

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The Mesozoic of the Osugi area in Mie Prefecture is divided into the Chichibu Terrane and the Shimanto Terrane. The Chichibu Terrane thrusts up to the Shimanto Terrane. Six units of sedimentary complexes are discriminated in the Chichibu Terrane, namely the Sannoko, Kitamatagawa, Okutamadani, Kuroishi, Daifugendake and Wasabidani complexes in tectonostratigraphically descending order, and in the southern margin of the Osugi area, the Obadanigawa and Akataki complexes are distributed in the Shimanto Terrane, whereas in the north part of the Osugi area, the Mayoidake Complex belonging to the Shimanto Terrane thrusts up to the Chichibu Terrane. Each complex of the Chichibu and Shimanto terranes is divided by thrust. For the Shimotakogawa Fault which has E-W strike, the southern geologic bodies were descended lower than the northern part. Furthermore the western geologic bodies in the Osugi area collapsed along the arcuate Kamataki Fault and the tuffite dyke swarm. In the Osugi area, all complexes attributed to the Chichibu Terrane were firstly formed as the accretionaly complexes during middle to late Jurassic. The complexes included to the Shimanto Terrane, were formed in late Cretaceous. The Mayoidake Complex thrust up to the Chichibu Terrane during Paleogene, and the southern geologic bodies were descended down by the Shimotakogawa Fault. The tuffite dyke swarm and Kamataki Fault were closely caused by the volcanic activity during middle Miocene.

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A detailed diatom analysis of one drilling core was carried out in the Fukushima-gata Lagoon area of the northern part of the Echigo Plain, which is situated in the inlet side of the Kitakanbara-gata Lagoon. 11 diatom divisions were detected and correlated with divisions of the Shiunji-gata Lagoon area (Yasui et al. 2002) situated in the inside part of the Kitakanbara-gata Lagoon. The characteristics of diatom assemblages and Holocene sedimentary environments of the Kitakanbara-gata Lagoon are discussed in this paper. Diatom assemblages of the Kitakanbara-gata Lagoon were characterized by flourish or decline of several maker planktonic species. In the Fukushima-gata Lagoon area three types of diatom assemblage appeared repeatedly. The first type is dominated by Aulacoseira granulata, which indicates limnophilous fresh surface water, and may be caused by a closure of an inlet. The first type took the place of the second type dominating by Cyclotella caspia, which is caused by an inflow of marine water from an inlet opening. The third type is characterized by a low frequency of planktonic species, which indicates rheophilous fresh surface water or a reduction of water area. The Holocene sedimentary environments of the Kitakanbara-gata Lagoon are identified as follows on the basis of diatom divisions and ^<14>C datings. The Kitakanbara-gata Lagoon was under a brackish lake environment in ca. 8,000 yrs BP, and three periods of marine surface water expansion occurred at ca. 6,500, from ca. 6,000 to ca. 5,000 and at 3,500 yrs BP. In ca. 3,000 yrs BP, the connection of the water area between Fukushima-gata Lagoon and Shiunji-gata Lagoon areas in the Kitakanbara-gata Lagoon were disappeared.

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A few fossil shark teeth were found in the laminated gray mudstone of the lower part of the Middle Miocene (15Ma) Iseyama Formation in Sanada-machi, Ueda-city, Nagano Prefecture, central Japan. These were identified as teeth of dogfish, Squalus sp.indet. This is the first record of the genus Squalus from the Northern Fossa Magna Region in Nagano Prefecture. Judging from the habitat of Squalus and the occurrences of shallow-sea fish fossils, such as Eosardinella hishinaiensis and Family Clupeidae, it is estimated that the sea which deposited the lower part of the Iseyama Formation was the continental or insular shelf and from shelf edge to shelf slope which was fell sharply from the shallow sea of coastal or bay zone with surface warm current.

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