GEOCHEMICAL JOURNAL
Online ISSN : 1880-5973
Print ISSN : 0016-7002
ISSN-L : 0016-7002
1 巻 , 4 号
選択された号の論文の4件中1~4を表示しています
  • Takashi Katsura
    1967 年 1 巻 4 号 p. 157-168
    発行日: 1967年
    公開日: 2008/04/08
    ジャーナル フリー
    The chemical composition of Pele's hair seems to be important for illustrating the variations in chemical compositions of the Hawaiian tholeiitic basalts including the iron-rich members. The tholeiites in Hawaii are divided into two groups: One includes a series of rocks whose compositions can be explained by mixing of the magma of Pele's hair and olivine, and the other includes those whose compositions can be explained by subtracting plagioclase and clinopyroxene from the magma of Pele's hair. By using the value of the mole ratio FeO/FeO1.5 in the Pele's hair, the liquidus temperature of the magma of Pele's hair is estimated to be 1, 160°±10°C at an oxygen partial pressure of 10-8.2 atm.
  • Ricardo Marcos Pytkowicz, Gerald Allan Fowler
    1967 年 1 巻 4 号 p. 169-182
    発行日: 1967年
    公開日: 2008/04/08
    ジャーナル フリー
    In situ pH electrodes were used to show that solution of pelagic calcareous foraminifera occurs in seawater at pressures between 100 and 1, 000 atm. The results confirm earlier work which had indicated that the carbonate compensation depth is not a boundary between super and undersaturated waters. The degree of solution and hence diagenetic alterations which may affect the geologic record were found to depend on the calcareous species. The results of this work also yielded physicochemical knowledge on the effect of pressure on carbonate ion pairs, on the relative solubilities of calcite and aragonite, and on rates of solution. There is no solubility in the thermodynamic sense but this fact was shown not to affect the value of solubility measurements for oceanographic and geochemical work.
  • Hiroshi Wakita, Hiroshi Nagasawa, Seiya Uyeda, Hisashi Kuno
    1967 年 1 巻 4 号 p. 183-198
    発行日: 1967年
    公開日: 2008/04/08
    ジャーナル フリー
    Neutron activation analysis of U, Th and K has been made on some possible mantle materials, mainly peridotite nodules from continental and oceanic areas. The paper first describes the analytical procedures of U and Th determinations. Results of analysis showed that oceanic nodules have more uniform concentrations of U, Th and K and Th/U, K/U ratios than continental nodules. Average values for 7 oceanic lherzolites are: (1.87±0.27)×10-8 gU/g, (5.48±0.87)×10-8 gTh/g, and (54.2±7.5)×10-6 gK/g, giving a rate of heat production, 26×10-16 cal/cm3·sec, which is about 70% of that for the average chondrite. There is no indication that oceanic lherzolites are more enriched in these elements than the continental ones. These results suggest that, from the thermal point of view, peridotite nodules may not be the representative constituent of the upper mantle, unless the oceanic mantle is capable of transferring heat exceedingly well. The average values of the ratios are Th/U=2.93±0.61, and K/U=(0.29±0.06)×104. The latter is significantly smaller than the crustal value (1×104), which is already smaller than the chondritic value (5×104).
  • Nobuyuki Nakai, Mead Leroy Jensen
    1967 年 1 巻 4 号 p. 199-210
    発行日: 1967年
    公開日: 2008/04/08
    ジャーナル フリー
    Sulfate samples from rain and snow water, collected in Japan and in U.S.A. have been studied isotopically in an attempt to determine the sources of atmospheric sulfur. δ34S values of the samples are 5 to 18 ‰ lighter than that of sea water sulfate. Based on these isotopic data, it is suggested that the most important sources of atmospheric sulfate are hydrogen sulfide derived from bacterial reduction of sulfate and SO2 from industrial activities. Sea spray sulfate is a minor contributor. In industrial sites, the sulfur in precipitation indicates depletion in 34S, viz. +3.2 to +7.3 ‰, in contrast to δ34S values in non-industrial sites, that vary from +12.3 to +19.0 ‰. It is suggested that the lighter isotopic composition of atmospheric sulfur may be explained by the contribution of light sulfur from sulfur bearing fuels through industrial burning.
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