出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.15, no.8, pp.643a-644, 1903

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.4, no.8, pp.387a-387a, 1892

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.108, no.4, pp.Plate1-Plate2, 1999

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.20, no.1, pp.59a-60, 1908

著者

山田 周二

出版者

Tokyo Geographical Society

雑誌

地學雜誌 (ISSN:0022135X)

巻号頁・発行日

vol.110, no.1, pp.79-93, 2001-02-25

被引用文献数

1 1

---

This study classified Japanese mountains based on mountain ordering using 1 : 500000 topographic maps, and examined the relationships of relief, relative relief and perimeter fractal dimension for the classified mountains. Mountain order was defined in terms of closed contour lines on the topographic map. A set of closed, concentric contour lines defines a first-order mountain. Higher-order mountains can be defined as a set of closed contour lines that contain lower-order mountains and that have only one closed contour line for each elevation. Relief, relative relief and fractal dimension were measured for ordered mountains using personal computer, and were defined as follows : relief <I>E = H/A</I><SUP>1/2</SUP>, where <I>H</I> and <I>A</I> are the height and area of each ordered mountain, respectively; relative relief <I>R</I>= ∑ <I>h<SUB>i</SUB>/H</I>, where <I>h<SUB>i</SUB></I> is the height of the enclosed, lower-order mountains, and represents the degree of vertical roughness of the ordered mountain; fractal dimension was measured for perimeter contour line by the pixel dilation method, and represents the degree of horizontal roughness of the ordered mountain. Japanese mountains were classified into 74 third order mountains and 11 fourth order mountains. The area of a third order mountain varies from 50 to 4712 km<SUP>2</SUP>, and that of a fourth order mountain is 2498 to 15563 km<SUP>2</SUP>. A significant relationship was found among relief <I>E</I>, relative relief <I>R</I>, and fractal dimension <I>D</I> for the ordered mountains (r=0.91, n=85), and can be defined by the expression : <BR>Log<I>E</I>=-a<I>D</I>-bLog<I>R</I>-c<BR>This relationship shows that Japanese mountains have the following morphological characteristics : a high relief mountain has low vertical and horizontal roughness, and a low relief mountain has high vertical and horizontal roughness. These characteristics suggest that slope angle of Japanese mountains converges within a certain range.

著者

Y C

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.33, no.4, pp.230a-231, 1921

著者

岩崎 重三

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.21, no.5, pp.353-356, 1909

著者

大森 房吉

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.32, no.4, pp.172-180, 1920

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.36, no.9, pp.558a-558a, 1924

著者

ホッペ グンナー 岩田 修二

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.90, no.2, pp.85-92, 1981

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せまい地域から地球的規模までの自然の理解や環境悪化の監視のための重要な方法であるリモートセンシング技術の最近の発展はたいへんめざましい。この技術がもっとも有効に利用されているのは低緯度地域においてであるが, 高緯度地域においても有効な技術であることはいうまでもない。<BR>米・ソの二大国が主導的な位置をしめるリモートセンシングの技術開発のなかにあって, スウェーデンは, ハッセルブラッドのカメラシステムとAGA赤外テレビシステムの開発という2つの重要な貢献をしている。<BR>スウェーデンにおける空中写真の利用は80年前に始まり, 氷河調査, 地形図・土地利用図の作製, 森林管理, 地形・地質の調査などに役立つてきた。空中写真利用の最近の興味深い例には, 北西スウェーデン山岳地域の開発計画のための組織的な空中写真判読作業や, 赤外カラー写真を利用した沿岸地域における海底地形図の作製, 森林帯における樹木の活性度の判定がある。空中写真の情報を数値化する試みも古くからおこなわれ, いくつかの映像読みとりシステムが開発された。また, 可視光と近赤外以外の波長域をカバーする装置も開発された。1973年には, リモートセンシング5力年計画として以下のものがとりあげられた。各種のセンサーを用いる全天候型のオイルもれ検知システム, 各国との協力で多様な方法を用いる海氷探知計画, マルチスペクトルスキャナーを用いた完全自動植生図化作業, レーザーを用いたばい煙検知システム。<BR>スウェーデンは人工衛星によるリモートセンシングにも古くから関心をもっていた。気象衛星の利用, ランドサットの映像の地質調査への応用などに始まって, 最近ではマルチスペクトルデーターを森林管理のために利用するためのコンピューターシステムが開発された。さらに, 土地利用地図のための自動図化装置の開発, バルチック海の生態系の解明のための技術開発などがおこなわれている。最近の重要な前進は, スウェーデン北部に衛星受信基地の建設が決定されたことである。あらたに始まろうとしている第二次5力年計画では, 将来打ちあげられる人工衛星からの情報の高度な利用が計画されている。なかでも, 1984年にフランスから打ちあげられる予定の衛星に対しては, スウェーデンも費用を負担しており, 高度な利用が期待されている。

著者

丸山 浩明 仁平 尊明

出版者

Tokyo Geographical Society

雑誌

地學雜誌 (ISSN:0022135X)

巻号頁・発行日

vol.114, no.1, pp.68-77, 2005-02-25

被引用文献数

1 1

著者

渡辺 満久 齋藤 勝

出版者

Tokyo Geographical Society

雑誌

地學雜誌 (ISSN:0022135X)

巻号頁・発行日

vol.115, no.6, pp.727-736, 2006-12-25

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The eastern margin of Echigo Plain, central Japan, is characterized by NNE-SSW trending active faults. The Anchi fault is made up of two segments : the Anchi-nishi fault and the Anchi-higashi fault. Each fault trace is approximately 2-km long. They may be short subsidiary faults on the hanging wall of the master fault in this region (the Tsukioka fault). Trench investigations across the Anchi fault reveal its rupture history as follows : 1) the Anchi-nishi fault and the Anchi-higashi fault are west-dipping reverse faults; 2) the Anchi-nishi fault shows a vertical offset of 1.3-1.9 m after ca. 30 ka; and, 3) the vertical displacement of 3.5 m is associated with two faulting events along the Anchi-higashi fault, one between ca. 30 and 60 ka and the other younger than ca. 30 ka. Geomorphic features indicate that a reverse fault branches into these two faults at a certain depth. Thus, the total vertical offset for the last ca. 30 ky is between 3.1 to 3.7 m. This value is one third of that along the master active fault. If the source fault consists of these active faults, we should evaluate the activity of the master fault taking account of the activity of the Anchi fault. It is very important to know the nature of subsidiary faults, even if they display very short traces.

著者

河角 広

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.79, no.3, pp.115-138, 1970

被引用文献数

13

---

In earlier days most Japanese wanted eagerly to have means of earthquake prediction in order to escape earthquake disaster taking refuge in advance in open spaces since they were almost powerless in encountering the menaces. We are now enabled to long for the mitigation of the disaster by the advancement of science and technology, although we have not yet succeeded to predict the coming of a disastrous earthquake. Our safety thus depend entirely on our effort for the countermeasures against the calamity. But we have only limited allowances for such preparations economically and in time available. It is therefore inevitable to start the preparation from the most important and imminent localities in a country, from the national point of view.<BR>In Japan, according to the writer's witness on the imminence of Southern Kwanto District at the Diet in July, 1964, such preparation work for Tokyo Metropolis was started the next month by a new Earthquake Division of the Disaster Prevention Council of the Metropolis, and several important hazard possibilities of the imminent earthquake have been revealed with the result that similar committees have also been made in other prefectures and cities in the same area as well as in the Central Government of the country.<BR>In this paper the writer intended to give the ground for his assertion of the imminence of a disastrous earthquake giving proofs of the periodicity of such calamities on the statistical and historical analyses, and made some comments on the possible consequences and major problems in the countermeasures to cope with the conceived disaster as revealed by the studies made on the national and metropolitan levels.<BR>In view of the importance, interest and the space allowance, only the proofs of the periodicity in the recurrence of destructive earthquakes in the district concerned are summarised in this abstract.<BR>Historical earthquakes in and around Kwanto District as shown in the map (Fig. 2.1) were examined and those which were destructive at Kamakura or presumable as such from the standard intensity-distance-magnitude curve were selected and listed in Table 1.1. Periodicities of these earthquakes were analysed statistically. Similar analyses were also applied to the earthquakes experienced in Tokyo which are listed in Table 2.2. A definite period τ of 69 years (besides a few integral multiples of this period) was clearly found. The methods used in the above analyses were by means of (1) Fourier transforms (Fig. 1.1), (2) autocorrelation functions (Figs. 1.3 and 1.4) and (3) historical examinations of the number of cases when no destructive earthquakes took place within the standard deviation +√ ξ<SUP>2</SUP> from the year t<SUB>p</SUB> when a destructive earthquake was expected to occur from the periodicity. Test of persistence of the period was also made by means of the theory of random walks consisting of Fourier amplitudes in successive periods (Figs. 1.5 a and b). Rayleigh-Schuster's criterion (Formula 1.3) that is the probability of obtaining the actual Fourier amplitude on the assumption of no periodicity or the resultant distance of above mentioned random walks gave the values of the probability equal to 0.06% and 0.03% for Kamakura and Tokyo respectively. In comparison to usual value of 5 or 10% for recognizing periodicity in geophysical phenomena, the smallness of the above values is more than enough to disprove the non-existence of the periodicity of 69 years in the recurrence of destructive earthquakes in the districts under consideration.

著者

立見 辰雄 菊池 徹 久野 久

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.66, no.1, pp.17-33, 1957

著者

大森 房吉

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.13, no.1, pp.18-24, 1901

著者

糸魚川 淳二

出版者

Tokyo Geographical Society

雑誌

地學雜誌 (ISSN:0022135X)

巻号頁・発行日

vol.118, no.4, pp.726-731, 2009-08-25

著者

松本 至巨 尾方 隆幸 内川 啓

出版者

Tokyo Geographical Society

雑誌

地學雜誌 (ISSN:0022135X)

巻号頁・発行日

vol.115, no.2, pp.221-235, 2006-04-25

被引用文献数

1 1

---

The Northern Japanese Alps (Chubusangaku National Park) has experienced a dramatic increase in the number of visitors since the boom referred to as "the Japanese hundred mountains". The Ushiro-Tateyama Range, located in the northernmost area of the Japanese Alps, provides various alpine landscapes such as cirques, asymmetrical ridges, patterned ground, perennial snow patches and alpine plant communities. Data from 6922 trekkers indicate that the distribution of mountain huts and accessibility to trails control their trekking courses, and that the trekkers concentrate in three mountain areas : Shirouma-mountain area, Goryu-mountain area and Kashima-mountain area. These areas are divided by a landform called kiretto, where a col with steep rockwalls lies along a main ridge, operating as a natural obstacle. Such a concentration suggests that human impacts on mountain geoecosystem occur locally, but intensively.

著者

小野 有五

出版者

Tokyo Geographical Society

雑誌

地學雜誌 (ISSN:0022135X)

巻号頁・発行日

vol.121, no.2, pp.187-214, 2012-04-25

被引用文献数

1 4 2

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Fifty years of studies on glacial landforms in Japan between 1960 and 2010 are reviewed from the personal perspective of a researcher who devoted a major part of his life to these studies. The 1960s was a period in which there was a paradigm shift in the history of glacial landform studies in Japan. This resulted from a series of studies by Tomoya Iozawa using aerial photograph interpretation. He was the first researcher to observe and identify all of the glacial landforms in Japan using aerial photographs, and divided them into two groups: the older and more widespread (Yokoo Stage) and the younger and much less widespread (Karasawa Stage). Following his methodology and staging, extensive research was done in the 1970s, and tephrochronological studies revealed that the older and younger stages correspond to MIS 4 and 2 respectively, although MIS 3 glaciation was recognized later in the Hidaka Range, Hokkaido. A researchers union of glacial and periglacial landforms called <i>Kanrei-chikei Danwakai</i> was established in 1972, Proposed and organized by Isozawa and other young students including the author, it stimulated research. In the 1980s, a reconstruction of the mass balance and flows of past glaciers from glacial landforms was attempted by the author and other researchers. This led to the estimation of the Equilibrium Line Altitude (ELA) of former glaciers in Japan. Inventory work and monitoring of perennial snow patches in the Japanese Alps were also begun in the 1980s, and they encouraged studies on the transformation from perennial snow patch to glacier. In addition, the discovery of an ice body at the bottom of Kuranosuke Cirque, Mt. Tateyama, Northern Japanese Alps gave an important hint to estimating the present (topographical) snowline altitude, which could be much lower than the former evaluation determined only from free air temperature. Both the study of perennial snow patches and mapping of the former ELA clarified the importance of precipitation when determining snowline altitude, and the present ELA was estimated at 2970 m just below the peak of Mt. Tateyama (3003 m). Since the 1990s, glacial landform studies became more closely related to global climatic change within the framework of IGBP-PAGES. Glacial fluctuations in Japan in the last glacial period were mainly controlled by monsoon changes and migration of westerlies, which caused a southern migration of the polar frontal zone. Although the glaciers in Japan were small, even in the glacial period, it is now believed that they are an important indicator of climatic changes because they are very sensitive to monsoon and westerly changes.

著者

米地 文夫

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.97, no.4, pp.317-325, 1988

被引用文献数

5 2

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.21, no.10, pp.723b-724, 1909