地学雑誌
Online ISSN : 1884-0884
Print ISSN : 0022-135X
ISSN-L : 0022-135X
116 巻 , 2 号
選択された号の論文の9件中1~9を表示しています
  • 中井 達郎
    2007 年 116 巻 2 号 p. 223-242
    発行日: 2007/04/25
    公開日: 2009/11/12
    ジャーナル フリー
    The spatial structures of a 101-103 m scale on coral reefs were understood by reading aerial photographs and investigating the topography of the fringing reef at the eastern part of Yoron Island, Ryukyu Islands. This study set a new physiographic unit (PGU) at the coral reefs as well as studied zonation. PGU has the following characteristics. (1) In an aerial photo, a linear pattern comprising micro-landform arrangements is recognized on the reef flat; (2) Seawater flowing beyond the reef crest from the open sea and entering the moat before returning to the open sea through a breakout in the reef crest or a channel flowing parallel to the shoreline constitute a very common pattern in the research area; (3) The series of currents observed in the area constitute a water system resembling a drainage water system on land and 4 systems were arranged at the eastern part of Yoron Island ; (4) The movement of seawater is controlled by landforms such as reef crests, channels and lands (a cape), which might qualify as borders of PGUs ; (5) Movements controlled by such landforms are dominant, and tend to be longer in terms of time. In this study, a physiographic unit is defined as follows. (1) A unit that is distinguishable from other adjacent areas by its geomorphological borders ; (2) And, a unit that is distinguishable from other adjacent areas when referring to the movement systems of seawater and materials.
    The notion of spatial structures of coral reefs of a 101-103 meter scale was substantiated by this research using the overlapping zonation approach known here as PGU on reef flats. The spatial structure makes a frame of the coral reef ecosystem. Therefore, setting a PGU is thought to be effective for application to coral reef conservation.
  • 村田 昌則, 鈴木 毅彦, 中山 俊雄, 川島 眞一, 川合 将文
    2007 年 116 巻 2 号 p. 243-259
    発行日: 2007/04/25
    公開日: 2009/11/12
    ジャーナル フリー
    Four boring cores obtained by boring surveys conducted at Wadabori Park in Suginami Ward (core WDB), Kinuta Park (core KNT) in Setagaya Ward, Tamagawadai Park (core TMG) and Unoki (core UNK) in Ota Ward, southeast part of Musashino upland, Tokyo, were reexamined. Mineral assemblage, shapes of volcanic glass shard, refractive indices of volcanic glass, and heavy minerals and chemical composition of volcanic glass of several tephra layers from these cores were determined. As a result, it is revealed that six tephra layers are correlative with the key tephra layers in the Kazusa Group of the Boso Peninsula and Tama Hills in the Kanto district. The WDB-1 tephra from core WDB is identified as the Kd8 tephra in the upper part of the Kiwada Formation in the Kazusa Group. The KNT-4 tephra from core KNT, the TMG-7 tephra from core TMG and the UNK-1 tephra from core UNK are identified as the Kd16 tephra in the middle part of the Kiwada Formation. The TMG-18 tephra from core TMG and the UNK-8 tephra from core UNK are identified as the Kd18 tephra in the middle part of the Kiwada Formation. Based on the correlation among these tephras, the sediments of ca. 15 m above sea level (a.s.l.) at Wadabori Park is correlative with the upper part of the Kiwada Formation deposited at 1.21-1.27 Ma, and the sediments of ca.-2 m a.s.l. at the Kinuta Park, ca.-20 to-74 m a.s.l. at the Tamagawadai Park and ca.-9 to-44 m a.s.l. at Unoki are correlative with the Kiwada Formation in the Kazusa Group. The sedimentary ages of these sediments are between 1.27 and 1.45 Ma based on stratigraphic relations with the calcareous nannofossil datums.
  • ギギ モセス ムリミ
    2007 年 116 巻 2 号 p. 260-274
    発行日: 2007/04/25
    公開日: 2009/11/12
    ジャーナル フリー
    2003年にケニアでは130万人以上がHIV/AIDSに感染するとともに15万人上が死亡しており, HIV/AIDSの伝染は国全体に大きな社会的インパクトを与え続けている。監視疫学のデータによると, 1990年以降HIV/AIDSの伝染は地域的に異なっており, それはHIV/AIDS伝染と国全体の疫病拡散およびその強度に関する要因との地域格差として現れている。国家的レベルでみると都市部でより感染率が高くなっているが, 県別の感染率と都市人口率との相関は有意ではない。しかしながら, 出稼ぎ労働者が故郷と都市部を定期的に移動することにより, 農村部および都市部の両方で一定の感染率が保たれている。感染率の高いNyanza県では貧困の度合いが高く, 貧困がHIWAIDS伝染の一因であると言える。しかしながら同じような貧困の度合いを示すNorth Eastem県では感染率が低く, HIV/AIDS伝染の空間的なダイナミクスに関する要因は貧困の度合いだけではない。また感染率と民族構成との相関をみると, ニロート族のエスニックグループと強い正の相関関係がある一方で, 中部バントゥ族や西ハム族, 東ハム族のグループとは負の相関関係があった。このことから, 伝染の空間的パターンには別の要因, とくに文化的慣行が影響しているのではないかと推定できる。さらに, HIV/AIDS感染を緩和するためにHIV/AIDSの監視システムをより地域的レベルへ拡大することで, HIV/AIDSの空間的パターンを規定する要因を調査する際に必要な情報提供が期待できる。
  • 新井 智一
    2007 年 116 巻 2 号 p. 275-286
    発行日: 2007/04/25
    公開日: 2009/11/12
    ジャーナル フリー
    In Japan, several American air force bases have raised the problem of aircraft noise pollution. This paper considers how municipalities around American air force bases have dealt with this problem. The study clarifies the relationship between aircraft noise pollution and compensation received in the municipalities around Yokota Air Force Base, an American air force base located near Tokyo, and the political actions taken by the municipalities against such pollution.
    Yokota Air Force Base was established in 1945. The functions of this base had expanded by the 1960s, so aircraft noise pollution intensified. Only Akishima City Council adopted many resolutions against aircraft noise. Aircraft noise pollution was not eliminated. Some inhabitants of Akishima City went to court to require the United States of America not to fly at night.
    The aircraft noise pollution intensified in Akishima City and Mizuho Town, which are located in the area where the runway of the base was extended. The national government has granted the municipalities subsidies as compensation for aircraft noise pollution. Fussa City, Musashi-Murayama City, and Mizuho Town have received large national subsidies. These municipalities did not adopt many resolutions against aircraft noise.
    The national government has increased the subsidies since 1974 in exchange for the consolidation of American air force bases in the Kanto Region into Yokota Air Force Base. The public finances of Akishima City have depended on subsidies because of urbanization.
    The compensation provided by the national government has been based on territoriality, although the pollution is unterritoriality. The political actions of the municipalities around the base have been segmented so aircraft noise pollution has not been eliminated.
  • 星野 一男
    2007 年 116 巻 2 号 p. 287-293
    発行日: 2007/04/25
    公開日: 2009/11/12
    ジャーナル フリー
    Rock mechanics belong to basic fields of science and technology, and are related to mining, oil, and civil engineering, as well as geology, geophysics, tectonics, and seismology.
    A national project of the underground caverns for oil storage was conducted throughout the 1980s and 1990s to study suitable construction sites. In this study, data on rock mechanics such as obtained by the rock deformation laboratory of the Geological Survey of Japan proved to be very valuable. These data were obtained from more than 500 rock specimens collected on foot from geologically representative localities nationwide. Finally, three sites, two consisted of granite and one of pyroclastic rock, were selected for construction. Detailed microscopic study of the failure pattern of specimens after the experiment indicated distinguishing brittle and ductile deformation characteristics. Brittle rock such as granite is harder in strength, sometimes with increased permeability; on the other hand, ductile rock such as pyroclastic rock is less permeable.
  • 小出 仁
    2007 年 116 巻 2 号 p. 294-296
    発行日: 2007/04/25
    公開日: 2009/11/12
    ジャーナル フリー
  • 西澤 修, 笠原 順三, 山川 修治
    2007 年 116 巻 2 号 p. 297-304
    発行日: 2007/04/25
    公開日: 2009/11/12
    ジャーナル フリー
  • 白尾 元理
    2007 年 116 巻 2 号 p. Plate1-Plate2
    発行日: 2007/04/25
    公開日: 2009/11/12
    ジャーナル フリー
  • 笠原 順三
    2007 年 116 巻 2 号 p. Plate3-Plate6
    発行日: 2007/04/25
    公開日: 2009/11/12
    ジャーナル フリー
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