All issues
Volume 17 (1969)
- Issue 4 Pages 798-
- Issue 3 Pages 685-
- Issue 2 Pages 589-
- Issue 1 Pages 426-
Volume 17, Issue 1
Displaying 1-12 of 12 articles from this issue
- |<
- <
- 1
- >
- >|
-
SASAKI NOBUJI1969 Volume 17 Issue 1 Pages 426-433
Published: March 01, 1969
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (724K) -
MATSUMOTO ATSURO1969 Volume 17 Issue 1 Pages 434-444
Published: March 01, 1969
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSImportance of geochronology is stressed in connection with three aspects of historical geology in Japan.The first is concerned with the time-scale and correlation, the second with the problems in the geological history of the Japanese Islands, and the third with some new ideas which have come from the study of the circum-Pacific orogenesis.View full abstractDownload PDF (976K) -
NOBUKAZU OKAZAKI1969 Volume 17 Issue 1 Pages 446-462
Published: March 01, 1969
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (2025K) -
KOH YUJIRO1969 Volume 17 Issue 1 Pages 464-473
Published: March 01, 1969
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (1053K) -
MATSUMOTO SATORU1969 Volume 17 Issue 1 Pages 474-494
Published: March 01, 1969
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA precise mass calibration method for mass spectrograph is studied theoretically and experimental investigations on the method are carried out with the BainbridgeJordan type apparatus and with the Ogata-Matsuda type apparatus.As a result, dispersion constants estimated with simultaneously exposed four dispersion lines among which there is no restriction, are in good agreement with those obtained by two symmetric pairs for the former apparatus.Also, it is indicated practically for the latter apparatus that those constants estimated with three dispersion lines are in complete accordance with those calculated from four dispersion lines by procedures for the corrections to a1.View full abstractDownload PDF (1978K) -
TOMOO OTUUJI, HIROSHI MIYAKE, MASAMI MICHIJIMA1969 Volume 17 Issue 1 Pages 496-499
Published: March 01, 1969
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSIt was tried to obtain mass spectra in a pulse counting mode with a continuous channel electron multiplier.Two continuous channel electron multiplier were used.One of them had length of about100mm, inside diameter of1.5mm and arc of270°.The resistance was about2×108Ω. Background rate was0.2cps at an applied voltage of3.0kV, 0.04cps at2.8kV and0.002cps at2.6kV. When argon ions were injected with an accelerating voltage of1kV, counting rate attained to plateau above2.3kV, and its slope was1.2%/100V. Pulse height distribution at3.0kV showed saturation. The other, which had length of about84mm, inside diameter of1mm, arc of480°and resistance of about1.5×108Ω, was mounted on a90° Kmagnetic deflection type mass spectrometer with100mm radius of curvature. Characteristics of this multiplier were studied and mass spectra of residual gas were obtained. This multiplier had background rate of2-3cps at2.4kV. Mass spectra obtained with a12stage Cu-Be electron multiplier in the pulse counting mode were also investigated.View full abstractDownload PDF (2504K) -
OSAMU NAKAMICHI, KENJI KONISHI, HITOSHI SAKAI1969 Volume 17 Issue 1 Pages 500-508
Published: March 01, 1969
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSCorals and pelecypods of Recent to Pleistocene age were analyzed for their isotopic ratio of oxygen and carbon by means of McCrea's technique. The precision and reproducibility of the isotopic analysis were found to be±0.08‰ forδ18 O and±0.15permil; forδ13C based on the analyses of NBS-20limestone over a period of six months. The effect on the isotopic ratio of roasting presentday and fossil carbonates in purified helium was also examined. In order to calibrate our standards against PDB scale, three different standards, of which the isotopic ratios have been corrected against the scale, were analyzed to gether with our standards. The results were, however, not consistent with each other and further study will be carried out to settle the problem. It was shown that the diagenetic alteration of aragonite skelton of Pleistocene coralsresulted in the depletion of13C in parallel with calcitization and dissolution of uranium.View full abstractDownload PDF (1833K) -
YOSHIO UEDA1969 Volume 17 Issue 1 Pages 510-513
Published: March 01, 1969
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe M/e 34-40 spectra of residual gases have been observed under static operation even at the pressure of the order of 10-9 mm Hg. These mass spectra, especially the M/e 36 spectmm, are the largest cause for the error in K-Ar geochronology. The method of correction of the peaks of M/e 36, 38and40in the background is discussed in this paper. We have obtained satisfactory result in the removal of the memory for the use of high concentrated gases by more than one hour bombardment of the Bayard-Alpert gauge.View full abstractDownload PDF (433K) -
ICHIRO KANEOKA1969 Volume 17 Issue 1 Pages 514-521
Published: March 01, 1969
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSThe argon retention of obsidian was studied with respect to the degree of hydration. It is found that there is a negative correlation between them. Consequently, forK-Ar dating, it is recommended to use obsidians whose H20(+)contents are small, say, below about0.5%of weight. It is also found that a rhyolite sample shows poorer argon retentivity than that of a fresh obsidian. The probable age of obsidian at Wada Toge (pass) is about0.9-1.1m. y..View full abstractDownload PDF (627K) -
SHINJI SATO, SHIGERU IIZUMI, HIROO KAGAMI1969 Volume 17 Issue 1 Pages 522-529
Published: March 01, 1969
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA standard sample JG-I, a granodiorite from Sori, Gunma Prefecture indicates the following isotopic compositions:Rb content has a range of178. 9to183. 4ppm;Sr content has a range of182. 5to187. 5ppm;the ratio of Sr87/Sr86 has a range of0. 7113to 0. 7121. The ratio of Rb87/Sr86, calculated from above data, has a range of2. 692to2. 839. In an isochron diagram, the error in vertical axis is ±0. 06%, and that in horizontal axis is±2. 6%. Thus, the error in the calculated age is?±10. 6%, in a case of the rock of which age is approximately100million years. When the correction of the multiplier was not adequate, the initial ratio of Sr87/Sr86 in isochron is also effected.View full abstractDownload PDF (729K) -
KOGORO MAEDA, AKIRA FUKUDA, MASAHIKO SAKIMURA1969 Volume 17 Issue 1 Pages 530-574
Published: March 01, 1969
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSTables of a, q and β values are presented for two types of the mass filter, towith iso-β-charts and also with the detailed charts near the apexes where combinations of the values of a and q are most frequently used for the practical purpose. Importance of the β value is mentioned for further studies of the mass filter problem.View full abstractDownload PDF (3397K) -
SHIGEL ANDO1969 Volume 17 Issue 1 Pages 576-583
Published: March 01, 1969
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (9038K)
- |<
- <
- 1
- >
- >|