地理学評論
Online ISSN : 2185-1719
Print ISSN : 0016-7444
ISSN-L : 0016-7444
9 巻, 8 号
選択された号の論文の9件中1~9を表示しています
  • 三野 與吉
    1933 年 9 巻 8 号 p. 649-674
    発行日: 1933/08/01
    公開日: 2008/12/24
    ジャーナル フリー
    In an earlier paper the author described his quantative studies of the crustal movements, and the crustal deformations of the same district. But in doing so he had to make the following assumptions:
    a) This district wa eroded to a peneplain during older. Tertiary (pre-miocene); an assumption held by many geologists, although it had not been determined geomorphologically or geographically, that is to say the distribution, both horizontal and vertical.
    b) The miocene deposits which are scattered here and there, on the summit of the hills and at the bottom of the valleys of this district, had covered much wider area at that time than it does today.
    c) The peneplain., or eroded surface, , developed during a late stage in the geographical cycle and had truncated in much the same way the tops of the surfaces of the. miocene and pre-miocene strata, so that an intersected penepain was developed, that is two peneplains (pre-miocene and post-miocene) had intersected each .other at a small angle. In this paper he attempts to prove these assumptions, the method being as follows :
    I. He has drawn. a “Gipfelflur” map (Fig. 1) by the method of closed contour curves on morphological maps (scale 1:50000; contour interval 20m ), publshed by the Imperial Japanese Military Land Survey.
    Fig. I shows many long ranges of mountain summits in a direction NW-ES, together with another range in a EN-SW direction.
    II. He has classified the flat plains in Fig. I into I, II, and III, from the lower, to the higher.
    Flat plains I are distributed mainly in the south and the north-west parts of the district, the former being the Ihara-Hutyû, and the latter- the Syôhara flat plain.
    Flat plains II are distributed in the socalled up-lifted Tyûgoku peneplain, the altitude of the northern parts being about 600m, and that of the southern about 450m. The southern extremities, which assume. a zig-zag form, spread out into the flat plain II, while the northern, which assume the same shape as the southern., penetrate under flatplain III. For example, the region of the upper course of the Tôzyô river (flat plain II), about 7.km in width and rokm in length, penetrates flat plain III of Mt. Iiyama, and Mt. Sirataki in the west, and Mt. Ogamesituzi in the east.
    Flat plain III, which is distributed chiefly in the northern part, is shaped like a peninsula. The parts which are distributed from the center to the southern end of the district have the shape of an island. The altitude increases from 750m.
    III. He. drew another “die Gipfelflur” (Fig. 4), in which he adopted a closed curve as before, but in this, he joined together greater distances (about 3 km) than those shown in Fig. I, then classified flat plain Fig. 5, from Fig. 4. This classified figure largely resembles Fig. 2.
    IV. In order to test the correctness of the classification of the flat plains as well as to ascertain their general altitudes and also the ratio of height deviation, the author drew parallel lines, spaced I km apart, and after obtaining the frequency polygon of every closed. curve in each of these spaces, or sections, divided those of 20m and 40m into class I and those of 60m and 80m into class II. To smooth the frequency polygons of the same class, he averaged the same frequency polygons in every three adjoining sections, the result being Fig. 6 (note the row of polygons).
    By selecting a geomorphological region as a unit, Baulig(2)drew frequency polygons of closed curves for the Paris Basin and Brittany. They do not however indicate clearly the. distribution and the relations of each flat plain to one another in a region.
    To interpret -the frequency polygons in Fig. 6, it is necessary to assume the following fcr this region.
  • 鹿野 忠雄
    1933 年 9 巻 8 号 p. 675-701
    発行日: 1933/08/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 木内 信藏
    1933 年 9 巻 8 号 p. 702-711
    発行日: 1933/08/01
    公開日: 2008/12/24
    ジャーナル フリー
    After the studying from topographical maps the recent lava flows that issued from Mt. Sakurazima, Mt. Asama, Mt. Huzi, etc., I have divided them into two classes, the zonal and fanshaped, as in Fig. 4. The forms due to various conditions, such as the physical and chemical properties of lava, the original topography, etc. But the problems dealt are restricted to form and shape, Most lava flows have complex features of folds, hills, and depressions, particularly, eracks, both transversal and diagonal (I have not yet come across longitudinal cracks). These flows are interesting, because of their resemblance in several ways to glaciers. I cannot illustrate any cracks in block lava flow.
  • 椙山 正英
    1933 年 9 巻 8 号 p. 712-724
    発行日: 1933/08/01
    公開日: 2008/12/24
    ジャーナル フリー
    Mt. Nagi apperes to present a subdued form, and on its southern side it goes down to the basin of Nihonbara as a scarp of the Nagisan fault. There are some low hills and dissected fans which seems to be of Tertiary age. A zone of soil of usual apperence extends in a W-E direction between the moutainland and the flat parts of the Tertiary beds and the alluvium, which the author thinks is colluvium. The term “colluvium” originally refered to a soil possesing certain petrographic characteristics. The author, however, used the word here for a certain soil accumlation based on geological and topographical characteristics.
    The colluvium consists of angular gravels of diameters less than 10cm, and probably covers to a certain extent the fault plane of Mt. Nagi. The inclination of the colluvium, which is 100 to 200‰, is steeper than that of ordinally alluvial fans and elevated deltas, but more gradual than that of talus. If the breadth of the valley of the upper stream is wide, the colluvium is accumulated in the form of a fan. In a series of valleys of smaller breadth, the colluvium forms a continuous surface, which should be called colluvial base.
    When the mountain at the back is of subdued form, that is, the elevation of the mountainland is proceeding at a very slow rate, and the conditions of the rock is suitable for the formation of the colluvium, it may be concluded that conditions are right for the deposition and accumulation of the colluvium.
  • 1933 年 9 巻 8 号 p. 725-728,741
    発行日: 1933/08/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 山口 貞夫
    1933 年 9 巻 8 号 p. 729-732
    発行日: 1933/08/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 山崎 禎一
    1933 年 9 巻 8 号 p. 732-736
    発行日: 1933/08/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 木内 信藏
    1933 年 9 巻 8 号 p. 736-737
    発行日: 1933/08/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 矢澤 大二
    1933 年 9 巻 8 号 p. 737-740
    発行日: 1933/08/01
    公開日: 2008/12/24
    ジャーナル フリー
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