The K-Ar ages were determined on twelve samples from granitic rocks and the associated ore deposits around the Kofu basin, Yamanashi Prefecture, Japan. Three host granodiorites give the K-Ar ages of 10.4±0.3 Ma (Shiodaira type of the Kofu granitic rocks), 8.9±0.3 Ma (Hirose type of the Kofu granitic rocks) and 10.7±0.3 Ma (Kai-Komagatake granitic rocks). Two biotite-hornfels derived from the Shimanto Supergroup give almost the same ages (11.7±0.3 Ma, 8.4±0.2 Ma) as those of the granitic rocks. Two samples of sericite from the Otome mine also giving the similar ages of 9.0±0.2 Ma and 9.5±0.2 Ma to those of host granitic rocks suggest the mineralization at the Otome mine took place just after the granite formation. Pegmatites and quartz veins in the granitic rocks give younger K-Ar ages (ca.1 to 3 Ma younger) than the host granitic rocks.

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球状酸化マンガン鉱は天然では海洋底のマンガン団塊として, また陸上の大規模鉱床に産する魚卵状マンガン鉱としてよく知られている. この球状酸化マンガン鉱の成長過程を明らかにするためにゲル法による合成実験を行った. すなわち, 苛性ソーダを含む寒天ゲルをガラスの試験管に入れ, その上に塩化マンガン溶液を注いだ. 溶液中のマンガンイオンは直ちに拡散してゲル中の水酸基イオンと反応して酸化マンガンの沈殿を生ずる. 生成物は大部分非晶質であり, 少量のハウスマン鉱とパイクロアイトを伴っている. 適当な条件下では沈殿物はリーゼガング・リングを作り, そのリングは粒子からできている場合が多い. 沈殿物中の粒子は球状を呈し, 天然の魚卵状のものと同様な同心円状の内部構造をもち, またある粒子は楕円体状, 紡錘状及び不規則な外形を示し, 天然のマンガン団塊によく見られる波状の外殻をもっている. 沈殿で出来た粒子は静かな生成環境であるにもかかわらず, 同心円状または波状の外殻をもっている. 天然の球状酸化マンガン鉱の生成にとっても, 複雑な波動的拡散現象が重要な役割を果たしていると考えられ, 周期的な堆積環境の変化は必ずしも必要としない.

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Strata-bound manganese oxide deposits are distributed in the Setana area, southwestern Hokkaido, Japan. The pre-Tertiary sedimentary rocks and plutonic rocks are located in the marginal region of the area to form a sedimentary basin. The Kunnui and Yakumo formation which consist of volcanic breccia and hard shale respectively, heaped up on the basin by neogene green tuff activity. Manganese deposits lie in the most upper part of the Kunnui formation or lie between the Kunnui and Yakumo formation. Therefore manganese deposits are considered to be formed in a same geological age. These deposits are located on the rim of the basin and regarded to have been formed by submarine hydrothermal activities based on the studies of field occurrence and geologic setting. Pyrolusite and manganite are the dominant manganese mineral. Groutite and todorokite are common but found in minor amounts.
The concentration in manganese ores of major and trace elements are measured by X-ray fluorescence method and rare earth elements (REE) are measured by neutron activation method. The data shows; (1) the data on manganese ores from the area fall in the hydrothermal area in the Mn-Fe-(Cu+Ni+Co)X10 ternary diagram. The trace elements concentration of several deposits show an influence of hydrogenous activity. (2) The concentration of Cu and Co vary widely among each locality, whereas Ni and Zn do not vary widely. The result is similar to that of the Tokoro area; the behavior of these elements originates from the tendency of adsorption of each transition element to manganese. (3) The total amount of REE is same to that of submarine hydrothermal deposits. The REE pattern normalized by chondrite shows positive Ce anomaly in the northern side of the basin and suggests the more oxic environment than the southern side of the basin. (4) The variation of trace elements concentration are relatively small in the Setana area. The data suggest that the manganese deposits in this area were formed by the hydrothermal activity under a nearly same condition as inferred from the geological study.

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Porous media are encountered actually everywhere in everyday life, in technology and in nature. With the exception of glass and metals, some dense rocks and some plastics, virtually all solid and semi-solid materials are porous to varying degrees. Pores in various types of rocks and materials usually contain some fluid, such as air, water, gas, oil, etc., or a mixture of different fluid facies. The concept of porosity and permeability of rocks and industrial materials might have been nearly missed till now when not only studying the geologic or hydrogeologic phenomena but elucidating the behavior of fluids in porous media, the fatal deterioration of industrial materials, the underground storing of oil, the underground disposal of industrial wastes, and so forth. It will be getting more and more important from now on.
In this paper, the scope and importance of pore characteristics and transport phenomena in porous media, such as building materials and industrial products as well as rocks, are reviewed and applicably discussed.

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