We have measured ³He/⁴He and ⁴He/²⁰Ne ratios, and ⁴He concentrations in water samples collected at several depths in the eastern Japan Sea. Observed ³He/⁴He and ⁴He/²⁰Ne ratios vary from 1.006R_atm (where R_atm is atmospheric ratio of 1.343×10^-6) to 1.045 R_atm and from 0.24 to 0.31, respectively. There is a difference in ⁴He concentration between in the samples shallower than 1,500m and those deeper than 2,000m. The discrepancy may be related to the existence of two water masses in the Japan Sea suggested by Gamo and Horibe (1983). Excess ³He in the shallower samples is attributable to tritium decay in the sea water while that in the deeper samples is not. Emanation of mantle helium is suggested in the Japan Sea bottom. Since the number of present data is small, extensive ³He/⁴He research should be carried out in future to verify the existence of mantle helium in the Jpan Sea.

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The whole concentrations of 19 constituents including major, minor and traceelements were determined for JLs-1 and JDo-1 samples issued from Geological Survey of Japan. The most remarkable feature of both samples is that they contain extremely low amounts of acid-insoluble residues. The relative enrichment of Ba and F compared with those of common carbonate rocks is also one of the specific feature of these samples.

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The ferruginous and calcareous spring deposits collected from Niusawa, Togetsuan and Tsuganero, Masutomi spring district, Yamanashi Prefecture, were analyzed and the chemical characteristics, change in chemical composition during the flow and the relationship between the spring water and the deposit were studied. (1) Near the outlet, there are ferruginous deposits which contain much amount of SiO₂, Na₂O, K₂O, P₂O₅, Cu, Zn, Ba and Ra. On the other hand, calcareous deposits are at the downflow, contain much amount of MgO. (2) At Niusawa, the contents of Na₂O, K₂O, P₂O₅, Cu, Ba, and Ra decreased with the distance from the outlet, which are correlated with the content of Fe₂O₃. While SiO₂ is abundant in the ferruginous deposits, Si/Fe ratio increased with the distance from the outlet. It is inferred that the amount of coprecipitated SiO₂ depends on the pH of the spring water. (3) The spring water temperature as well as the concentrations of Fe²⁺, HCO₃^- and Ca²⁺ decreased and pH increased during the flow. Calcium carbonate is in supersaturation. Its ion activity product is 3 times larger at inlet and 27 times larger at calcareous deposit than its solubility product. The Sr distribution coefficient between calcium carbonate and spring water is 0.17 which is in good agreement with the other data obtained from calcite.

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Phosphorus in surface sediments from Tokyo Bay and its estuaries was classified by a consecutive extraction technique with acid and alkali. The acid-extractable phosphorus fraction decreased remarkably at the transition zone between riverine environment and marine one, strongly suggesting desorption of phosphorus from sediment particles. A core sample from the central part of the bay showed that phosphorus content at the surface was two times as high as that at 60cm below. Most of the increase in recent years was ascribed to a result of human activities. The amount of phosphorus buried in sediments, however, was not proportional to the increased phosphorus input to the bay. Therefore, most phosphorus input at present is eventually flushed out into outer sea without settling in the bay, although the input activity keeps primary productivity high in the bay.

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The samples of quartz-calcite vein obtained from 8 boring cores around Kushikino gold-silver mine, Kagoshima prefecture, were analyzed by neutron activation analysis. Contents of gold, silver and rare earth elements (lanthanum, cerium, samarium, europium, terbium and ytterbium) were determined. Gold contents in Kushikino area near gold-silver mine were higher than those in Kammuridake area near heat source. Ag /Au ratios were below 10 in Kushikino area while about 100 in Kammuridake area. Relative abundance patterns of rare earth elements normalized to the chondrite (Ln_sample/Ln_chondrite) values showed gradual depletion in heavy REE and had positive europium anomaly. The normalized values by the chondrite showed approximately linear correlation with ionic radius of REEs, and slopes [log(Ln_sample/Ln_chondrite)/r] of the straight lines are obviously different between Kushikino area (average 8.5) and Kammuridake area (average 6.2).

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