巻号一覧
26 巻 (1972)
- 6 号 p. 235-
- 5 号 p. 183-
- 4 号 p. 139-
- 3 号 p. 91-
- 2 号 p. 47-
- 1 号 p. 1-
26 巻, 5 号
選択された号の論文の5件中1～5を表示しています
- |<
- <
- 1
- >
- >|
-
西男鹿団体研究グループ原稿種別: 本文
1972 年 26 巻 5 号 p. 183-194a
発行日: 1972/09/25
公開日: 2017/07/26
ジャーナル オープンアクセスMiocene volcanics and their pyroclastic rocks called the Kamo lavas and the Shinzan rhyolites after HUZIOKA (1959) are widely distributed in this district. The lowest member consists of porphyritic trachytic-andesites, probably correctable to MIYAGI (1956)'s Kuguriiwa lavas, and is conformably overlain by the "Kamo lavas". The Kamo lavas are divided into two members.the lower (basalts) and the upper (porphyritic two-pyroxene andesites). They are unconformably overlain by the Tateshima conglomerate (newly named by the authors) which is chiefly composed of subrounded gravels of porphyritic two-pyroxene andesites and altered basalts. The "Shinzan rhyolites" cover the above all members including the Kamo lavas usually with unconformity. The "Shinzan rhyolites" are subdivided into the first stage eruptive type and the second and third stage intrusive types. The well sorted and/or graded pyroclastic beds are found often intercalated with the Kamo lavas, the Tateshima conglomerate and the first stage rhyolites, suggesting that the volcanic .action in this district had happened in a fresh water environment. The presence of the Tateshima conglomerate may be considered to mean the following tectonic history: eruption of the Kamo lavas→fracturing followed by local tilting which is to be continued intermittently→formation of the local depression→sedimentation of the Tateshima conglomerate→eruption and intrusion of the Shinzan rhyolites (first, second and third stages). It is noted that there are shown general coincidence of structural direction between faults, dykes and flow structures of rhyolites (chiefly second stage), trending NNE〜NE-SSW〜SW. This may indicate the intimate relationship between eruption and intrusion of rhyolites and fracturing. As for the mode of occurrence and structural aspect of the intrusive type rhyolites, the second stage rhyolites may be dyke-form, whereas the third stage may be lava-dome form.抄録全体を表示PDF形式でダウンロード (2981K) -
紀州四万十帯団体研究グループ原稿種別: 本文
1972 年 26 巻 5 号 p. 195-204b
発行日: 1972/09/25
公開日: 2017/07/26
ジャーナル オープンアクセスThe stratigraphy and geologic structure of the Muro Group in the Upperreaches of Koza River were described in this paper. The Muro Group is divided lithologically into three parts. The lower part is composed of massive sandstones inter calated by conglomerates and the middle part is composed of massive sandstones and sandy flysch, and the upper part is composed of shales and muddy flysch accompanying pebbly mudstones and conglomerates frequently. The total thickness attains to about 6700-7900m. Tectonically, the surveyed area is divided into two blocks by Matsune-Hirai thrust fault. The northern block takes a part of southern limb of Kohgawa syncline and has undulated structures, while the southern block, which belongs to the other tectonic division, has complicated structures. It is noteworthy that in the surveyed area open folds and closed folds of various scales exist together. Paleocurrent analysis by current marks, such as flute cast, groove cast, bounce cast and brush cast, indicates that the sediments of the middle part were transported and settled mainly by longitudinal currents from WSW to ENE and partly by lateral currents from N to S. Exotic orthoquartzite gravels were discovered in many conglomerates beds regardless of their horizon. These gravels are smaller in size and lesser in quantity than the same gravels found in the southern coastal region of the Kii Peninsula.抄録全体を表示PDF形式でダウンロード (3100K) -
領家研究グループ原稿種別: 本文
1972 年 26 巻 5 号 p. 205-216
発行日: 1972/09/25
公開日: 2017/07/26
ジャーナル オープンアクセスVarious kinds of granitic rocks are exposed in the Ryoke metamorphic belt. We established the phase-division of intrusions of these granitic rocks, by recent re-investigation in Central Japan. According to the evident intrusion-relation and the correlation of petrographic character theses granitic rocks are divided into those of nine phases as follows; 1st phase Hiji and Kamihara quartz-diorites 2nd ,, Tenryukyo and Minakata granites 3rd ,, Kiyosaki granite and Katsuma quartzdiorite 4th ,, Mitsuhashi and Ikuta granites 5th ,, Inagawa granite 6th ,, Ichida granite 7th ,, Busetsu and Kadoshima granites 8th ,, Takato and Kisokoma granites 9th ,, Naegi-Agematsu granite The granitic rocks of 5th to 9th phases are evidently younger than the Nohi rhyolites of late Cretaceous age. On the other hand, the granitic rocks of 1st to 4th phases never come in contact with the Nohi rhyolites, at least in the present surface. The geological map of the Ryoke belt in Central Japan attached to this paper has been newly compiled, based on the above division of granitic rocks.抄録全体を表示PDF形式でダウンロード (1704K) -
河内 洋佑原稿種別: 本文
1972 年 26 巻 5 号 p. 217-232
発行日: 1972/09/25
公開日: 2017/07/26
ジャーナル オープンアクセスDetailed discussion of spindle stage technique is presented. It includes principle, construction of the spindle stage, preparation and mounting of mineral fragments, care and accuracy of measurements such as illumination, bracketing, color fringe, focal plane screening, etc. Refractive index as well as optic axial angle determination is treated. A revised technique of that of NOBLE (1968) for axial angle measurement is described. Advantages and a brief history of development of the technique are reviewed. Finally, a simple microrefractometer for use with the spindle stage is presented.抄録全体を表示PDF形式でダウンロード (1773K) -
鈴木 敬治原稿種別: 本文
1972 年 26 巻 5 号 p. 233-235
発行日: 1972/09/25
公開日: 2017/07/26
ジャーナル オープンアクセスPDF形式でダウンロード (852K)
- |<
- <
- 1
- >
- >|