アルゼンチン,パタゴニヤ地方には多数の裂か充填型蛍石鉱脈が見出される.これらの鉱脈のあるものについて系統的にその鉱脈を横切って採取された蛍石試料中の液体包有物の充填温度を測定した結果明かに次の傾向が認められた.
(1)多くの場合,鉱脈の中心部の幾分上盤よりから採取した蛍石中の液体包有物の充填温度の平均値は最高値を示し,両盤へ向ってその平均値は次第に低下する.
(2)上盤近くから採取した.蛍石の充填温度の平均値が最高値を示し下盤へ向って次第に低下する傾向の認められる場合があるがその例は少ない.
(3)鉱脈を横切ってのこの様な温度勾配は鉱脈の走向に沿っての温度勾配に比し遙に大きい.
統計的分析の結果はこの様な傾向が大きな確率のもので実在すると考え得る事を示す.蛍石中の液体包有物の充填温度と共生する鉱物や母岩の種類との間に何等の相関性も認められなかった.

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Molybdenum and tungsten deposits provide clear examples of ores related to granitic rocks. The writer (ISHIHARA, 1971a) has pointed out that tungsten deposits tend to be associated with less acid intrusions than molybdenum deposits and that scheelite (not wolframite) in non-calcareous wall rocks occurs where the source granitic magma is calcic. He also proposed a new scheme of the Mo-W metallogenic provinces of Japan, the Kitakami district of which shows a reverse pattern in lateral zoning of those of the Inner Zone of Southwest Japan (ISHIHARA, 1971b). Fundamental data and reasons for the above proposals taken from the Kitakami district have not yet been 'published. This paper, as a sequel to the previous two papers, describes zonal distribution of the metals and nature of the granitic rocks of the Kitakami district. Genesis of the metallogenic provinces of Japan is discussed in terms of the plate tectonics model.
The Cretaceous-Paleogene granitic rocks in the Honshu Island show definitely regional variation in composition. It is basic at one side (either continental or oceanic) and becomes acidic at the other side. This is tentatively called "Lateral differentiation trend", and is shown by changes in regional bulk composition and in ratios of Fe⁺³/Fe⁺², NA/K, Th/K, U/K, Rb/K, etc. of the granitic rocks, and distribution of the Mo-W deposits. One suite of these variation is considered as the most fundamental unit of petrogenetic province. Each province consists of subprovinces such as Mo-, W-, and Barren provinces.
The lateral diffentiation trend is continentward in the Inner Zone of Southwest Japan (arrows in Fig. 9), but oceanward in the Abukuma and Kitakami Belts. Hence, the most distinct discontinuity appears some place along the present Tanakura tectonic line. The asymmetrical zoning in the Inner Zone of Southwest Japan (see Table 5) can be explained by a magmatic differentiation model during ascending of granitic magma along a continentward-dipping weak zone in crust or Benioff zone itself. This hypothesis was discussed in this paper in emphasizing role of H₂O and differences on volatilities of Cl- and F-complexes. This hypothesis implies that Northeast Japan belonged to a different plate from that of the Inner Zone of Southwest Japan and also the paleo-Benioff zone or the conduit of the granitic magma inclined steeply oceanward at the Cretaceous time.

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This study on the vein-type mineralization in the Josen Honpi mining area, Kishu mine, involves statistical analyses and some genetic considerations derived from various results of the analyses and conventional geological data. The factors used for the analyses are strike, dip, width and grade of the veins. The statistical distribution charts obtained from these factors are given in figures on the Schmidt's net and frequency figures of the veins. These figures respectively show the vein structure and close relationship between the vein system and the geologic structure. Some situations of mineralization are calculated from the correlation between Cu% and S%, dip and strike, richness (grade × width of vein), width, etc.
The distribution graphs of Cu% and value of S/Cu show the position of copper bonanza and suggest ore shoot. The main current of copper-bearing solution passed through the E14 block at No.5 adit level and rose diagonally to the west and then went through the E12 block at No.3 adit level and reached No.2 adit level. In other words, it rose to the upper part in the D member (alternation of sandstone and shale) and then farther to the C member (medium-grained sandstone).One of the tributaries to the main current flowed into fissures at right angles to the synclinal axis of the country rocks in this area and formed the veins of the W1 block at No.2 adit level. Then, the tributary went down to the W1 block at No.3 adit level.

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古遠部黒鉱鉱床産の各種含重晶石一方鉛鉱鉱石について,重晶石中の鉛含有量の変化を原子吸光分析法により検討した.その結果,同鉱体中の重晶石に含まれるPbSO₄濃度はほぼ10～200ppmの範囲内にあり,鉱化作用の初期から後期に向って一般にわずかながら増加する傾向が認められた.
既報の重晶石一方鉛鉱平衡に関する原理(KAJIWARA and HONMA, 1972)に基づいて解釈すると,同鉱体の生成峙における温度および酸素フュガシィティーの変化はそれほど大きくなかったことが推定される.すなわち.
1) 鉱化時の温度がほぼ一定に保たれたと仮定すると,酸素フュガシィティーは鉱化初期から後期に向って,わずか約0.5程度(対数単位で)しか上昇しなかったことになり,
2) 逆に,鉱化時の酸素フュガシィティーがほぼ一定に保たれたと仮定すると,鉱化初期から後期に向って温度は約10℃程度しか低下しなかったことになる.
観察される鉱石の累帯配列もこのようなごくわずかの温度や酸素フュガシィティーの変化により生成した可能性がある.

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