GLACIAL LANDFORMS AND PLEISTOCENE GLACIATION IN THE OHTSUMETAZAWA VALLEY, SOUTHEASTERN PART OF THE MT. KASHIMAYARI, USHIRO-TATEYAMA MOUNTAIN RANGE, NORTHERN JAPANESE ALPS

DOI Web Site Web Site 7 Citations

Bibliographic Information

Other Title
  • 後立山連峰,鹿島槍ヶ岳,大冷沢流域における氷河地形と氷河前進期
  • 後立山連峰,鹿島槍ケ岳,大冷沢流域における氷河地形と氷河前進期
  • ウシロタテヤマ レンポウ カシマ ヤリ

Search this article

Abstract

The authors investigated in detail the glacial landforms in the Ohtsumetazawa Valley, south-eastern area of Mt. Kashima.yari (2, 889.7m) through field surveys and aerophoto-interpretation. In the estimation for the location of terminal moraines and corresponding outwash terraces (Fig. 5), and for the difference of dissection of glacial landforms, three glacial stades were recognized. They are named according to the old age, Ohtanihara, Kitamata and Nunobikisawa stades respectively. On the other hand, the existance of Ni-shimata stade is possibly recognized between the Ohtanihara and the Kitamata stades by the estimation of the distribution and the facis of the outwash terrace (Terrace III), though the terminal moraine in this stade is not discovered yet. Fig. 3 shows the glacier distribution at each stade.<br> By trenching the top ridge of the Ohtanihara terminal moraine, which was formed in the Ohtanihara stade, the authors discovered three marker-tephras: the DPm and EPm pumices of the Tateyama Volcano and the DKP pumice of the Daisen Volcano (Fig. 14). They were identified by the examination of their petrographic characteristics (Table 2). According to their inferred age (Machida and Arai, 1979; Machida, 1980; Machida et aL, 1985), the age of the Ohtanihara stade is, at least, before 100, 000 y. B. P. Therefore the authors interpreted the Ohtanihara stale as the penultimate glacial (Riss Glacial).<br> Along the middle to lower reaches of the Kashima River, the terraces developed. They are tephrochronologically classified into Terrace I to IV (Figs. 15 and 16). The topographical relation between the glacial landforms and these terraces indicate that the accumulation periods of several terrace gravel coincide with the glacial stades as follows: A) Ohtanihara stade : Terrace II, B) Nishimata stade : Terrace III, C) Kitamata stade: Terrace IV. The Terrace II is covered with the DPm, and the Terrace III is covered with the EPm, while the Terrace IV is not covered with any tephra. On the basis of the presumed age of these pumices, the ages of four glacial stades are estimated as follows: 1) Ohtanihara stade: older than 100, 000 y. B. P.; 2) Nishimata stade: older than 60, 000y. B. P.; 3) Kita-mata stade: about 20, 000y. B. P. and 4) Nunobikisawa stade: after 20, 000 y. B. P.

Journal

Citations (7)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top