地理学評論
Online ISSN : 2185-1719
Print ISSN : 0016-7444
ISSN-L : 0016-7444
9 巻, 1 号
選択された号の論文の9件中1~9を表示しています
  • 福井 英一郎
    1933 年 9 巻 1 号 p. 1-19
    発行日: 1933/01/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 渡邉 光
    1933 年 9 巻 1 号 p. 20-36
    発行日: 1933/01/01
    公開日: 2008/12/24
    ジャーナル フリー
    In this article are presented, some of the salient features of the, land forms of a minute area comprising the western periphery of the Cumberland plateau in the east and also the eastern margin of the Highland Rim plateau in the west (Fig. 1). The area in consideration is a type locality, showing the contact of two peneplanes differing in elevation as well as in the age of formation.
    The western edge of the Cumberland plateau, the surface of which is generally regarded as a Cretaceous peneplane, has already attained the mature stage of dissection, with small remnants of the original surfaces on the interstream highlands (Fig. 2). But the dissection of the Highland Rim plateau, an early Tertiary peneplane, is still in its infancy. These levels reach heights of 1, 400 feet and 1, 000 feet respectively, with topographic break of 400 feet between them. The boundary line between these levels is highly indented, and the Highland Rim level penetrates deeply into the Cumberland plateau as wide, open valleys of dendritic pattern (Fig. 2). “Inselberg”-like outliers of the Cumberland plateau protrude profusely upon the Highland Rim level along its eastern. margin (Fig. 3). Long sweeping lines characterize the profiles of the slopes of the valleys and the outlier hills, and there is an accumulation of colluvial materials at their base.
    The plateau series is chiefly composed of Mississippian limestone in the Highland Rim plateau, and a thin capping of Pennsylvanian sandstone is recognizable in the Cumberland plateau. These series lie nearly horizontal, dipping slightly southeastward, although small dome-like disturbances are found in several localities. The Highland Rim level truncates the area regardless of the underlying structure, so that the uppermost series of pure limestone appears near its eastern margin and on the valley floors further to the east, and the older series of impure limestone come to the surface as one goes away northwestward from the marginal area.
    Karst topography is well developed on the Highland Rim level as well as on the slopes of the outlier hills and valley walls. Dolines, uvales, and limestone caves are plentiful on the surface (Fig. 5). The Cumberland river and its major tributaries intrench about 300 feet through the Highland Rim level, still preserving the meandering courses that have been inherited from the free meanders upon the peneplane surface. The plateau is dissected by these rivers and by the insequent streams developed from the steep valley walls. However, the recession of the slopes of the outlier hills and the widening of the valleys in the Cumberland, plateau are still going on with the Highland Rim peneplane as the local base level of erosion. Therefore, we are able to assert that the Highland Rim peneplane is still in course of formation along its eastern margin, showing that this continuous level is by no means of a contemporaneous origin. Karsting on this level has been rejuvenated by the lowering of the corrasion basis, due to general rejuvenation of the area.
    The degree of dissection of the Highland Rim plateau is controled by the nature of the limestone. Karsting predominates along its eastern margin where the pure limestone comes to the surface. There the dissection of the surface has been greatly retarded by the absence of surface streams (Fig. 4 and Fig. 5). However, in its western portion, and especially in areas of structural domes, where the impure limestone happens to appear on the plateau surface, the dissection is in a more. advanced. stage compared with adjacent areas (Fig. 6).
    Along the course of the Cumberland river are found erosion levels about 80 to 100 feet below the Highland Rim surface, separated only by slopes of gentle gradient from the latter (Fig. 4).
  • 尾崎 乕四郎
    1933 年 9 巻 1 号 p. 37-49
    発行日: 1933/01/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 松澤 勲
    1933 年 9 巻 1 号 p. 50-69
    発行日: 1933/01/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 1933 年 9 巻 1 号 p. 70-72,87
    発行日: 1933/01/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 西田 正夫
    1933 年 9 巻 1 号 p. 73-76
    発行日: 1933/01/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 山崎 禎一
    1933 年 9 巻 1 号 p. 76-82
    発行日: 1933/01/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 能 登志雄
    1933 年 9 巻 1 号 p. 82-83
    発行日: 1933/01/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 岡田 修
    1933 年 9 巻 1 号 p. 83-86
    発行日: 1933/01/01
    公開日: 2008/12/24
    ジャーナル フリー
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