Thirty-six Quaternary volcanic rocks from the central and eastern Hokkaido, whose major elements were known, were newly analyzed on the minor elements, Cu, Sr, Ba, Ga, Y, Pb, V, Cr, Co and Ni. The relation between the minor and major element abundances of the above rocks were discussed. The general and characteristic features of the volcanoes and volcanic chains are summarized as follows;
1. The kutcharo, Atosanupuri and other post-caldera volcanoes of Kutcharo and Mashu have the same character as those of the Usu and Esan volcanoes of the south-western Hokkaido.
2. Also the Akan volcano has the same character as those of the above volcanoes, except Cu, Cr and Ni elements. This volcano is far richer in these elements than those of the others.
3. The Daisetsu and tokachi volcanoes have nearly the same character as that of the Niseko Volcano of the southwestern Hokkaido. The Daisetsu Volcano is characterized by the high V×1000/FeO+Fe₂O₃ ratio, which is one of the highest value in Hokkaido, and by the rich Cr and Ni contents. The Tokachi Volcano is far poorer in Cr and Ni than The Daisetsu Volcano.
4. The difference of minor element contents between the shiretoko-Akan and the Daisetsu-Tokachi volcanic chains is best represented in Ba and Pb contents. The latter is richer in Ba and Pb than those of the former.
In the Shiretoko-Akan volcanic chain, the rocks of the pigeonitic rock series are richer in V than those of the hypersthenic rock series, as seen in the volcanoes of that in the south-western Hokkaido. The rocks of the Daisetsu-Tokachi volcanic chain, which belong mostly to the hypersthenic rock series, are rich in V and plotted in the pigeonitic rock series field of the rocks from the former chain. In this point, the rocks of the hypersthenic rock series of the latter chain are different from those of the former.
The minor elements of the Tokachi welded tuff are often far from the general character of the Tokachi volcano, which suggests its different genesis.

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The Kabasawa placer deposit is categorized as one of the Pliocene ilmenite placer deposit and its sedimentary and conservative environment is controlled by warping movement of the Okubushi line.
the purpose of this paper lies in the research of such elements which influenced the deposition of the Kabasawa placer deposit characteristics relating to type of movement, behavior and development stage of the Okubushi line made during the Pliocene era.
The Okubushi line consists of combinations of cross structure of NW and NE branches meeting at tangent angles to each other which reflects the tectonics in the basement of this area. Of these, the NW brach plays a main role in the tectonic movement.
The NW branch of Okubushi line controlled the deposition in Pliocene Sendai Group as well as Pliocene sedimentary basin after making warping movement and bringing about an upheaval on its southwestern side and tilting subsidence on its northeastern side.
In other words, the NW branch brought about a differential movement of upheaval and subsidence through the depositional stage of Kameoka and Tatsunokuchi formation and the central part of the past upheaval changed into a depressional tilting subsidence at the depositional stage of Kitayama formation. Finally, the NW branch terminated its geologic movement with the eruption of tuff (acidic volcanic deposits) at the depositional stage of Hirosegawa tuff.
The Kabasawa sandstone and conglomerate member intercalating Kabasawa ilmenite placer deposit, is a deltaic deposit which was piled up upon the region of depressional tilting subsidence during the depositional stage of Kitayama formation. It forms a circle of 2km diameter and has an extraordinary thick stratum.
It is generally believed that the movement in the NW branch of Okubushi line is the result of a tectonic movement, referred to as “Green Tuff Crustal Movement”, in full activity during the Miocene era and succeeded to the Pliocene era in the northeastern part of Japan.

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The fission-track ages were obtained on zircons from tuffs of the Neogene Tertiary in Oga Peninsula, Akita Prefecture, Japan, as follows:
Shibikawa Group: Pink Tuff 2.8 m. y.
Wakimoto Group: Middle Tuff 6.8
Kitaura Group: Kitaura Tuff 7.5
Funakawa Group: Anzenji Tuff 12
Minami-Hirasawa Tuff 13
Nishikurosawa Group: Nishikurosawa Tuff 16
Daijima Group: Sugoroku Pumice-Flow 25
Hokakejima Welded Tuff 20
Monzen Group: Shinzan Rhyolite 26
Hornblende Biotite Adamellite 62

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Synthetic anorthite has been used as starting materials and altered in aluminum sulfate solution under hydrothermal conditions. Various chemical behaviors are shown under the influence of temperatures and running times. At 200°C, leaching value of SiO₂ is smaller than at 100°C, being greatest at 300°C. Leaching value of A1₂0₃ at 100°C is larger than at 200°C. A1₂O₃ decreases in the early-middle stages (50-150 hours) and rapidly increases in the later stage (260 hours) of 300°C runs. In the early stage of 300°C runs, CaO decreases rapidly and then decreases gradually until 260 hours. Desilification progresses gradually at 100°C and 200°C runs, and in the early stage of 300°C runs, shows an upward tendency. Desilification declines rapidly in the middle stage, and then tends to show upturned curve once again in the later stage of 300°C runs. These chemical behaviors can be harmonized when the combinations of following fundamental alteration processes are involved: (1) decomposition of anorthite, (2) variation of mineral paragenesis (gypsum, anhydrite, kaolin and boehmite, etc.) in alteration processes, and (3) relative quantity of alteration minerals.

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