出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.2, no.12, pp.654a-654a, 1890

著者

苅谷 愛彦 高岡 貞夫 佐藤 剛

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.122, no.4, pp.768-790, 2013-08-25 (Released:2013-09-11)

参考文献数

63

被引用文献数

12 13

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We studied the geomorphological and geological characteristics of four medium- to large-scale landslides that occurred in the alpine and subalpine zones of the northern Japanese Alps and assessed the relationship between landslide features and vegetation diversity in the landslide areas. To achieve this, we conducted field investigation and laboratory work including airphoto interpretation and radiometric dating of soils and fossil logs. Our field investigations indicate that, even in alpine and subalpine zones, landslide blocks (i.e., landslide deposition areas) display specific landforms such as scarplets, shallow depressions, and low mounds with linear or curved forms. Vegetation cover and aquatic areas such as peat bogs and moors also display linear or curved patterns that are superimposed on these small topographic features. We found that the highly diverse landscapes in landslide blocks were substantially different from those in present-day or fossil periglacial slopes near the main ridges, both of which displayed monotonous facies. The specific patterns of vegetation cover seen on landslide blocks probably formed under the influence of different slope environments, with variations of parameters such as inclination, soil properties, thermal-water regimes, and microclimate occurring as a result of landslide activities. Similarly, geomorphic changes such as channel migration and waterfall formation in and around areas of landsliding probably affected biological evolution and differentiation, and resulted in multiple modulations of the gene expression of aquatic organisms. Medium- to large-scale landslides are often reactivated by secondary movement. We suggest that subsequent variations of the landforms in the landslide blocks caused sudden or gradual changes in the surrounding natural environments, which had been forming since the initial mass movement. The biota present in a landslide block is the result of evolution and differentiation during geomorphic changes such as those described here; therefore, it is possible that secondary landsliding resulted in increased biological diversity and complexity.

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.41, no.2, pp.122a-123, 1929

著者

猪間 收三郎

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.52, no.7, pp.337-341, 1940-07-15 (Released:2010-10-13)

著者

松井 圭介

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.123, no.4, pp.451-471, 2014

被引用文献数

4

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The distribution and landscape of temples and shrines and their functions in the City of Edo are examined, and urban structures constructed based on mystical and religious aspects of spatial design are evaluated.<br> The five key findings of this study are:<br> 1. A city design modeled on <i>Heiankyou</i> (ancient Kyoto) was applied to the construction of the City of Edo, and was arranged according to four directions and their connections with gods. This model was meant to protect the City of Edo not only militarily, but also in magical and religious ways. In particular, large temples and <i>chinju-sha</i> shrines, which were strongly associated with the Tokugawa shogunate family, were placed to face northeast/southwest—directions regarded as being unlucky—as well as towards places of execution and the locations of red-light districts in areas bordering the city. This placement created an extraordinary atmosphere in the city. Tokugawa Ieyasu was awarded a posthumous <i>shingo</i> (literally, a Shinto deity) title, "Tosho Daigongen," and was enshrined angled towards the North Star (i.e. <i>Nikko</i>) to protect the City of Edo. The attempt to harness these magical factors to protect and safeguard the City of Edo is one of its characteristics.<br> 2. Temples and shrines were under the control of the Tokugawa shogunate during the Edo Period, and the <i>Honmatsu-seido</i> (government-enforced main-branch temple system) was established through the enactment of <i>jiinhatto</i> (laws for temples). In addition, members of the public were forcibly linked to temples and shrines through their status as <i>danka</i> (temple supporters) under the <i>Terauke seido</i> (a system that compelled the public to become Buddhists). Through this administration of religion, temples were integrated into a system for maintaining social order as a marginal role in the mechanism of the Tokugawa shogunate.<br> 3. The temple and shrine estates as a whole were almost the same size as the space allocated for the townspeople, and occupied a large proportion of the City of Edo in terms of land use. Shrines increased rapidly in number as the city's population increased. As a result, control measures were introduced to restrict the establishment of temples in the city's central area, where strong demand had led to a severe land shortage, and these temples were instead almost forcibly moved to the suburbs. This tendency became more evident in city planning after the Great Fire of Meireki in 1657; subsequently, new "towns of temples" were created in districts such as Asakusa, Shitata, and Mita.<br> 4. The rapid expansion of urban areas in the City of Edo led to religious facilities using their precincts as places to lease land and rent houses. As a result, new <i>monzen-machi</i> (temple towns) were created within the precincts of large temples, and some of these towns developed into entertainment districts, housing performing arts and drama facilities.<br>(View PDF for the rest of the abstract.)

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.21, no.1, pp.69a-69a, 1909

著者

中村 洋一 ハリー グリッケン

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.97, no.4, pp.309-316, 1988-08-25 (Released:2011-02-17)

参考文献数

24

被引用文献数

4 9

著者

渡辺了

出版者

東京地学協会

雑誌

地学雑誌

巻号頁・発行日

vol.114, no.6, 2005

著者

伯野 元彦

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.115, no.4, pp.466-469, 2006-08-25 (Released:2009-11-12)

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Recent earthquake damage in Japan has the following features. 1) Damage is not proportional to the recorded acceleration of earthquake. 2) Damage on the soft ground is severer. 3) Most of damage comes from the collapse of old wooden houses. 4) 40% of fires after earthquake are related to electricity.

著者

鈴木 毅彦

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.99, no.2, pp.182-197, 1990-04-25 (Released:2009-11-12)

参考文献数

35

被引用文献数

6 6

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Akagi volcano situated in the North Kanto district of central Japan is a Quaternary volcano. The eruptive history of this volcano during the last 200, 000 years is clarified by the tephrochronological study.The plinian pumice fall deposits derived from Akagi volcano are as follows in ascending order; the Moka Pumice (MoP), Akagi-Mizunuma Pumice-16. …-12, -10…-1 (MzP-16…-12, -10…-1), Namekawa Pumice-2, -1 (Nm-2, -1), Yunokuchi Pumice (UP) and Kanuma Pumice (KP) (Fig. 1). Stratigraphy, distributions and petrographic characteristics of these tephras are described (Figs. 5, 6, 8, 9 and Tables 1, 3).The MoP pumice fall deposit covering the most part of the eastern part of the North Kanto district, erupted in the penultimate glacial stage preceding the Last Interglacial Stage. Moreover, the stratigraphic relations of the MzP-10…-1, Nm-2, -1 and UP with the well dated widespread tephras, which are the K1P-7 (ca. 130 ka), DPm, On-Pm I (ca. 80 ka), K-Tz (ca. 75-80 ka), Aso-4 (ca.. 70 ka) and DKP (ca. 45-48 ka), are clarified (Fig. 7). These data can give the chronological framework for the eruptive history.The MzP series, Nm-2, Nm-1 and UP erupted during the stage called the younger stratovolcano (YS) of the Akagi volcano in previous work (Fig. 10). The total volume of the plinian pumice fall deposits from the MzP-10 to the UP amounts to 28 km3. This corresponds to the discharge rate of the pumice equivalent to 0.33 km3/1, 000 years and the frequency of the plinian eruption 0.15/1, 000 years.Before the formation of the central cone, it occurred the most eruptive episode of Akagi volcano. This is represented by the members : the KP pumice fall deposit (ca. 31-32 ka) and the Mizunuma lithic (chert lapilli) fall deposit (CLP). The volume of the KP deposit which amounts to 25 km3, is the largest volume of the plinian pumice fall deposits derived from Akagi volcano.

著者

小泉 尚嗣

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

pp.2012ap03, (Released:2012-12-05)

参考文献数

62

被引用文献数

7 6

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Research on coseismic and postseismic groundwater pressure changes is important for evaluating long-term groundwater stability in seismically active regions such as Japan. It is also important for preventing and reducing earthquake-induced geological disasters such as landslides. This study reviews literature and clarifies abrupt coseismic changes and subsequent postseismic gradual changes in groundwater pressure. Coseismic changes result from ground shaking and coseismic crustal deformation. Postseismic changes are gradual changes, which can be described by a diffusion equation with new initial values and boundary conditions due to ground shaking and coseismic crustal deformation. The effects of crustal deformation on groundwater pressure appear to be limited in the vicinity of the seismic source region, although that of ground shaking can remain in distant areas. Because a variety of factors and conditions affect earthquake-related groundwater pressure changes, each should be investigated to more accurately clarify the effects on coseismic and postseismic groundwater pressure changes. This research may contribute toward clarifying seismicity mechanisms triggered by distant earthquakes.

著者

三野 與吉

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.43, no.5, pp.256-267, 1931

被引用文献数

1

著者

小泉 武栄

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.120, no.5, pp.761-774, 2011-10-25 (Released:2012-01-17)

参考文献数

20

被引用文献数

4 6 6

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A geopark involves not only a geological heritage but also geographical and ecological elements. Therefore, subjects related to geotourism are not only landforms and geology, but also ecosystems, including vegetation and animal communities, and human landscapes, such as terraced rice paddies and grasslands created by human activity. Because geotourism covers a broad range of elements, from geo- and ecosystems to human activities, it is expected that the further development of related activities will be supported and approved by an increasing number of people. In this manuscript, I introduce some examples of geo-ecotourism as a special type of geotourism, including: vegetation at the summit area of Mount Hakusan, vegetation in a landslide scar on Mount Bandaisan, and the habitat of Dicentra peregrine on Mount Yatsugatake. These were all very popular with the participants of excursions I conducted. Geotours also promote regional development because they benefit residents economically by employing local workers and travel-related businesses, and encourage consumption of local services and products by visitors. A pressing issue concerning geotourism in Japan is the development of human resources such as tour guides. A geotour needs an excellent guide with a riveting interpretation. There are, however, few of such guides and there is a need to rapidly foster more. As a model for fostering guides, I introduce my “Intensive course on the natural history of mountains,” which interprets the natural history of mountains based on geo-ecology. In the long term, however, it is necessary to introduce natural history education into the school system and improve the quality of nature programs broadcast on TV. Many participants of geotours are middle aged and older, and tend to be energetic and slow to age. This may be because the tour participants are required to do physical activity and to use their common sense. Based on this perspective, a geopark approach must gain in importance within social and lifelong education.

著者

角田 寿喜 後藤 和彦 宮町 宏樹 平野 舟一郎 清水 力 岩切 一宏 中辻 剛 立山 清二

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.106, no.4, pp.476-485, 1997-08-25 (Released:2009-11-12)

参考文献数

26

被引用文献数

1

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A shallow earthquake of MJMA 6.7 on October 18, 1995, at about 50km southeast off Kikai-jima in the Ryukyu Islands caused slope landslides, subsidence of concrete slabs at fishing ports and collapses of walls piled up with coral ragged stones. Several fishing boats moored to wharves were damaged by tsunami; four boats were turned over at ports in Amami-Oshima.From May 19 to 30, 1995, earthquakes of MJMA≤4.1 had occurred in the focal area after a long seismic quiescence since the 1911 Kikai-jima Earthquake of M=8.0. Some of them were felt in JMA intensity 1 or 2 at Kikai-jima. Numerous felt shocks also struck the island immediately after the main shock; 62 and 125 shocks on October 18 and 19, respectively. Numbers of aftershocks decreased rapidly, though they lasted through the end of 1996.The damage distribution of the 1911 event being compared with that of the 1995 event, their focal areas were considered to overlap with each other. It was, however, possibly an interplate earthquake of a thrust fault type in contrast with the 1995 event of a normal fault type in the subducting plate, because the first motions of P wave at Naze and of tsunami wave at Kikai-jima were reversed between the two events.

著者

宇佐美 龍夫

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.94, no.7, pp.656-664, 1986-01-25 (Released:2009-11-12)

参考文献数

6

著者

長谷川 昭 中島 淳一 内田 直希 梁田 高広 岡田 知己 趙 大鵬 松澤 暢 海野 徳仁

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.121, no.1, pp.128-160, 2012-02-25 (Released:2012-03-05)

参考文献数

120

被引用文献数

6 12

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The mechanisms that generate the three main types of earthquake in subduction zones are discussed addressing their relations to geofluids. Studies on the spatial distribution of earthquakes and seismic velocity structure within the subducted slab provide evidence that strongly supports the dehydration embrittlement hypothesis for the generation of intermediate-depth intraslab earthquakes. Detailed imaging of the seismic velocity structure in and around plate boundary zones suggests that interplate coupling is mainly controlled by local fluid over-pressure. Seismic tomography studies show the existence of inclined sheet-like seismic low-velocity zones in the mantle wedge, not only in Tohoku but also in other areas in Japan, which perhaps correspond to the upwelling flow of the subduction-induced convection system. These upwelling flows reach the Moho directly beneath the volcanic areas, suggesting that those volcanic areas are formed by the upwelling flows. Aqueous fluids derived from the slab are probably transported up through the upwelling flows to the arc crust, where they might weaken the surrounding crustal rocks and finally cause shallow inland earthquakes. All of these observations suggest that geofluids expelled from the subducting slab play an important role in the generation of earthquakes in subduction zones.

著者

中谷 友樹 矢野 桂司

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.117, no.2, pp.506-521, 2008-04-25 (Released:2010-06-02)

参考文献数

37

被引用文献数

3 6

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To detect spatio-temporal pattern of crime clusters/hotspots, the possibilities of three-dimensional mapping methodologies for crime event data are explored using two approaches: three dimensional kernel-density mapping using a volume rendering technique and visualisation of cylindrical significant clusters that can be detected by space-time scan statistics. Both approaches are intended to visualise spatio-temporal domains with high densities of crime in a three-dimensional space composed of two geographical dimensions and one time dimension. The proposed three-dimensional mapping methodologies are evaluated through application to a dataset of snatch-and-run offences in Kyoto City during the period 2003-2004. The results are summarized as follows: (a) Three-dimensional crime mapping enables effective visualisation of the geographical extents and duration of crime hotspots simultaneously. This method is particularly useful to identify geographical diffusion and movements of crime clusters/hotspots compared to traditional dynamic analyses of crime mapping using cross-sectional maps with arbitrary time intervals.  (b) In practice, the roles of three-dimensional kernel mapping and space-time scan statistics should be complementary. Space-time scan statistics provide clear-cut domains of crime clusters/hotspots that can be used for secondary analyses, such as evaluation of socio-environmental and temporal characteristics focusing on detected domains. However, we should note that the method assumes cylindrical geometrical-constrains of space-time domains. Three-dimensional kernel density mapping provides fuzzy domains with high densities of crime and a useful basis to assess the validity of the assumption of spatial scan statistics and to investigate detailed space-time sequences of crime clusters/hotspots. (c) Empirical analyses of the snatch-and-run offence dataset in Kyoto City revealed constant clusters/hotspots during the study period in central Kyoto and around Kyoto Station as well as transient clusters/hotspots around several railway stations in the suburbs. Temporal differences of transient clusters show geographical movements of hotspots from the north to the south via the west. We also identified that outbreaks of snatch-and-run offences alternated between a pair of cluster areas. These results suggesting so-called displacement phenomena indicate the need to monitor crime events and effects of crime-preventive actions in a widespread space-time context.

著者

沢村 武雄

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.60, no.4, pp.190-194, 1951-12-30 (Released:2009-11-12)

参考文献数

10

被引用文献数

3 1

著者

古川 雅英

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.102, no.7, pp.Plate6-Plate6, 1993-12-25 (Released:2009-11-12)

著者

廣野 哲朗 小村 健太朗 藤本 光一郎 伊藤 久男 ジェームズ モリ ジロウ 佐藤 比呂志

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.122, no.2, pp.323-342, 2013-04-25 (Released:2013-05-31)

参考文献数

111

被引用文献数

2 2

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Several fault-drilling projects have been conducted with the common aim of seeking direct access to zones of active faulting and understanding the fundamental processes governing earthquakes and fault behavior, as well as the factors that control their natural variability. Here, we review recent scientific drilling projects related to the Nojima Fault which slipped during the 1995 Hyogo-ken Nanbu Earthquake, the Chelungpu Fault which slipped during the 1999 Taiwan Chi-Chi earthquake, the San Andreas Fault Observatory at Depth, and the Nankai Trough Seismogenic Zone Experiment. We also briefly introduce the ongoing drilling research by the Geophysical Observatory at the North Anatolian Fault Zone, the Deep Fault Drilling Project at the Alpine Fault, and the Japan Trench Fast Drilling Project. One of the main findings of fault-drilling research is a better understanding of the physico-chemical processes of the primary slip zone during an earthquake, which is closely related to the mechanism of dynamic fault weakening. In the case of the Chelungpu fault, integrated research with borehole experiments, core sample analyses, and numerical simulations were performed, and the results indicate that thermal pressurization occurred during the 1999 earthquake, explaining the peculiar seismic behavior during the earthquake. These fault-drilling projects related to active faults certainly improve our knowledge and understanding of earthquakes. In addition, we discuss new technical problems related to handling core samples, identifying the latest slip zone, and overprinting by ancient earthquake events.