地理学評論
Online ISSN : 2185-1719
Print ISSN : 0016-7444
ISSN-L : 0016-7444
11 巻, 8 号
選択された号の論文の8件中1~8を表示しています
  • 新野 弘
    1935 年 11 巻 8 号 p. 679-687_2
    発行日: 1935/08/01
    公開日: 2008/12/24
    ジャーナル フリー
    Tosabae is a marine bank situated at the entrance of Kii Strait 50km off the coast of Cape Muroto, Tosa Province.
    Its shallowest part is 154m in the western corner of the bank. The bank, which is outlined by a 400m bathymetric line, is oval, 31km long and 15km broad. In 1927 the surveying ship, “Sôyô-maru” of the Imperial Fisheries Experimental Station dredged many bottom samples from the bank, the predominant materials being rock fragments, followed by gravels, sands, and organic remains.
    1. Rock fragments. These are calcareous and marly shale, fine black sandstone, and gabbro. The calcareous shale under the microscope shows tests of fossil foraminifera, such as Rotalia sp., Globigerina sp., and Lenticulina rotulata Lamark. Only one, piece of gabbro was found among the rock fragments. It is greenish gray and shows fine schistose structure. Under the microscope, most of the crystals of monoclinic pyroxene are crushed and in parts have the parallel structure of mylonite.
    2. Gravels. Two gravels of marly shale were found in the bottom samples; of angular shape but very smooth surface.
    3. Sands. The sand grains consist of organic remains, quartz, feldspar, hornblende, etc.
    The abrade percentage of the quartz grains in the sand is far greater than that of the quartz grains in the rock.
    5. Organisms. The organic remains are foraminifera, coral, bryozoa, and mollusca.
    The Tosabae bank, which rises from the deep sea floor outside the continental shelf around Cape Muroto, is separated from the cape by a trench more than 700m deep, across which it is most natural to conclude that transportation of rock from the terrestrial region of Sikoku is impossible for which reason the dredgings are of geological importance, being probably the components forming the main part of the bank. The lithological characters of the sedimentary rocks just mentioned are found in the geological elements making up the Neogene Tertiary developed in Aki Province near Cape Muroto. Gabbro is also found in the Akigawa series, the Mesozoic formation developed at Cape Muroto. The bank of Tosabae therefore is closely related both geologically and topographically to the terrestrial part of the Muroto region.
  • 木内 信藏
    1935 年 11 巻 8 号 p. 688-702
    発行日: 1935/08/01
    公開日: 2008/12/24
    ジャーナル フリー
    As a test of the quantitative method, the relation between the height and area in the every zoom contour of volcanoes was studied. This “sectionless” method (no sections made of the volcanoes) has both advantages and dis-advantages. The area increase every 100m is also calculated in order to explain the hypsographic curve (shown by a broken line in figure). Since below a certain height, other mountains beside the volcano may be cut by the same contour lines, by critical height (in the figure chain lines) is meant that height below which mountains other than the volcano are not considered.
    First, three volcanoes are selected (1, 2, 3 in Fig. 12), namely, one with cone almost a logarithmic curve or hyperbola, a lava dome with straight lines, and a shield shaped volcano with a flat curve. The curves are classified by their apparent shape based on knowledge of their geology and topography.
    1 The dome type: Mt. Hutago (2 in Fig. 12), Mt. Miyatuka of Niizima island (2).
    2 The shield type: Mt. Gassan (1), Mt. Hakkoda (10), Mt. Hanna (13 & Fig. 6)
    3 The confide type: a. Dome with wide Susono (surrounding skirt) Mt. Sanbe (7 & Fig. 3), Mt. Daisen (6), Mt. Oakan (12 & Fig. 5) (somewhat different type)
    b. Flat type: 1st. example, with very. wide skirt contracting wide skirt contracting to a steep or small top (lava domes and eroded conides), Mt. Akagi (Fig. 12, 14), 2nd. example with caldera, Idu Oosima (island) (16)
    c. Type intermediate between b and d: Miyake island (15 & Fig. 8), Mt. Asama (17), Mt. Iwate (18 & Fig. 9), Mt. Tyôkai (Fig. 24), Mt. Yatugatake (22) (only its southern part).
    d. Huzi type: logarithmic curve: Mt. Siribesi Mt. Huzi, Mt. Iwaki (26), Mt. Komagatake in Hokkiadô (27), Mt. Bandai. (11).
    e. With a small skirt: Mt. Kaimon (1), Mt. Komagatake in Hakone (2). Mt. Turumi (21), Mt. Nantai (20).
    Finally the effects of erosion or disintegration on the hypsographic curve are summarized from a number of examples, such as the hypsographic curve moving to the left, causing steepness, and the increasicg curve causing irregularities in these.
  • 辻村 太郎, 山口 貞夫
    1935 年 11 巻 8 号 p. 703-728
    発行日: 1935/08/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 1935 年 11 巻 8 号 p. 729-738,753
    発行日: 1935/08/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 高橋 純一
    1935 年 11 巻 8 号 p. 739-745
    発行日: 1935/08/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 大井 芳雄
    1935 年 11 巻 8 号 p. 746-748
    発行日: 1935/08/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 大井 芳雄
    1935 年 11 巻 8 号 p. 748-752
    発行日: 1935/08/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 1935 年 11 巻 8 号 p. 760
    発行日: 1935年
    公開日: 2008/12/24
    ジャーナル フリー
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