巻号一覧
22 巻, 1 号
選択された号の論文の5件中1～5を表示しています
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Toshio Ishizuka, Yoshiyuki Nozaki, Kenji Shimooka1988 年 22 巻 1 号 p. 1-8
発行日: 1988年
公開日: 2008/04/08
ジャーナル フリーWe here report the results of dissolved free amino acid and hydrolyzable amino acid analysis for interstitial water samples collected from two ESOPE long cores (SNAP core 48 and GME core 10). Dissolved free amino acids (DFAA) in the ESOPE samples constitute, in most cases, less than 20% of the total hydrolyzable amino acids in the pore water. Their concentration varies rather systematically with depth in correlation with that of dissolved species such as nitrate, nitrite and manganese for SNAP core 48 and silicate and phosphate for GME core 10. In contrast, the concentration of total hydrolyzable amino acids (THAA) varies with depth by as much as two orders of magnitude. This may be because the organic matter from which the THAA are freed by hydrolysis is strongly associated with sediments and hence has poor mobility through interstitial water. The various individual amino acids show no systematic changes in relative abundance with depth which suggests that the bacteria which decompose organic matter in the deep-sea sedimentary environment do not significantly discriminate among the various amino acids.抄録全体を表示PDF形式でダウンロード (1981K) -
Jean-Louis Zimmermann, Albert Jambon, Gilbert Guyetand1988 年 22 巻 1 号 p. 9-21
発行日: 1988年
公開日: 2008/04/08
ジャーナル フリーA procedure of volatile analysis in rocks which permits quantitative estimation of all the volatile species of any geological interest is presented and illustrated by several examples. Gas extraction is performed either by vacuum crushing or heating. A separation line using cold traps, oxidation (CO to CO2) and reduction (H2O to H2) furnaces permits to separate several fractions. At the end of each separation phase the pressure in the line is measured with a capacitance manometer before analysis of the gas mixture with a mass spectrometer. Calibration is done periodically using standard gases stored in gauged bottles. The detection limits are 0.5 to 1. × 10-7 mol H2O, 0.3 × 10-7 mol CO2 and about 0.2 × 10-7 mol for H2, N2, CO, CH4 and Ar. Further species like organic compounds, SO2 and H2S are detected but not determined. In the case of H2O and CO2 the reproducibility is better than 4%. The conjunction of vacuum crushing, stepwise heating and size fraction analysis permits to separate components like: dissolved, adsorbed and vesicle trapped. In particular, effects of adsorption have been evaluated: it is a serious problem for, species like CO2 and H2O with finely crushed material. H2 and CO detected after thermal extraction when organic compounds are present in the sample reflect organic decomposition rather than any thermodynamic equilibrium attained upon rock formation.抄録全体を表示PDF形式でダウンロード (3679K) -
Hiroshi Shimizu, Tokuko Watanabe, Teruo Henmi, Akimasa Masuda, Hajime ...1988 年 22 巻 1 号 p. 23-31
発行日: 1988年
公開日: 2008/04/08
ジャーナル フリーThe high-resolution 29Si- and 27Al-NMR spectra and ESR spectra for five allophanes (SiO2/Al2O3=1.19, 1.22, 1.75, 1.77 and 1.90) are reported, together with the spectra for two imogolites (SiO2/Al2O3 = 0.96 and 1.0) and a halloysite (SiO2/Al2O3 = 2.0). It is apparently seen that 29Si-NMR spectra for allophanes vary depending on SiO2/Al2O3 ratios, indicating structural variations of allophanes with the change of the SiO2/Al2O3 ratios. Allophanes with SiO2/Al2O3 molar ratios close to 1.0 show a broad absorption at -79 ppm with a second, minor resonance around 90 ppm in the 29Si-NMR spectra; this suggests that orthosilicate is a main component of allophanes with lower SiO2/Al2O3 ratios. On the other hand, allophanes with higher SiO2/Al2O3 ratios show complicated 29Si-NMR spectra with several peaks between -79 and -97 ppm; these spectra indicate that these allophanes contain Si atoms in the orthosilicate structure as well as several different states of polymerized silicates with various Si-O-Si angles and Si-O bond strengths. Further, it is indicated that the relative abundances of polymerized silicates to orthosilicate tend to increase with the increase of the SiO2/Al2O3 ratio of allophane samples up to 1.75 and decrease at higher ratios. 27Al-NMR spectra for four allophanes studied show the resonance mainly at the chemical shift of 2.9-4.1 ppm, indicative of six-coordinated Al.抄録全体を表示PDF形式でダウンロード (2544K) -
Chitoshi Mizota, Minoru Kusakabe, Masami Noto1988 年 22 巻 1 号 p. 33-40
発行日: 1988年
公開日: 2008/04/08
ジャーナル フリーOrigin of the fine-grained quartz in soils and sediments developed on the Pleistocene terrace deposits and volcanic materials in southern Shizuoka, central Japan, was studied in view of the particle-size distribution and oxygen isotope composition of their constituent quartz. Most soil and sediment quartz occurs in the fractions finer than 53 μm in diameter with monomodal particle-size distribution, reflecting the effects of eolian sorting. The particle-size, however, is somewhat larger than that of the long-distance eolian dusts from the inland of the Asian continent (14 to 36 μm vs. 11 to 13 μ m particle-size peak). The oxygen isotope compositions of fine aerosol-size quartz (1-10 μm) separated from these surficial materials range from +16.2 to +18.7‰, by up to 3‰ higher than that of the eolian dusts from inland of the Asian continent (+16‰), and by 0.3 to 1.7‰ lower than that of the local river bed deposits. The data indicate that the quartz in the surficial soils and sediments is a mixture of the continental and local eolian additions.抄録全体を表示PDF形式でダウンロード (2056K) -
Chitoshi Mizota, Minoru Kusakabe, Masami Noto1988 年 22 巻 1 号 p. 41-46
発行日: 1988年
公開日: 2008/04/08
ジャーナル フリーFour red-colored soils and associated underlying Cretaceous limestones in Greece were analysed for content, particle-size distribution and oxygen isotope composition of quartz. Very low content of quartz in the limestones and lack of correspondence between the particle-size distribution of quartz in the soils and that in the limestones suggest that the overlying soils did not develop entirely from the weathering residuum of the underlying limestones. The particle-size of soil quartz decreases with increasing elevation of the sample sites. Soils developed at a lower altitude (∼50 m, A.S.L.) are likely to have accumulated coarse-grained eolian quartz winnowed from local beach sands when the sea level was lowered during the glacial period. The range of δ18O values from +17.6 to +19.3‰ obtained for the aerosol-sized quartz (1-10 μm in diameter) is characteristic of eolian dusts in the Northern Hemisphere, indicating its derivation from a well-mixed source of quartz of diverse origins. Such a restricted range of δ18O values contrasts notably with the wider range of δ18O values of quartz from the underlying limestones (+19.6 to +27.5‰). It is concluded that long-travelled Sahara dusts, together with a local eolian contribution are responsible for the soil development on the Cretaceous limestones in Greece.抄録全体を表示PDF形式でダウンロード (1496K)
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