著者

Ritsuro MIYAWAKI

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.131, no.2, pp.125-128, 2022-04-25 (Released:2022-05-13)

参考文献数

11

著者

上野 勝美 Tamara I. NEMYROVSKA

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.5, pp.919-932, 2008-10-25 (Released:2010-04-27)

参考文献数

22

被引用文献数

7 8

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To better understand and update knowledge of the stratigraphy and foraminiferal and conodont faunal successions of Bashkirian-Moscovian (Pennsylvanian/Upper Carboniferous) boundary intervals in the Donets Basin of Ukraine, we studied the C21 to C26 suites (Limestones F to L) of the following eight stratigraphic sections located in the eastern part of the basin. These are the Karaguz, Volnukhino, Kriven'ky Yar, Rudnya, Zolotaya, and Malonikolaevka sections in Lugansk county and the Soroch'ya and Kholodnaya sections in Donetsk county. Among them, the Malonikolaevka section, which is located about 35km southwest of Lugansk and is documented for the first time in this study, provides important data on the faunal successions of the Bashkirian-Moscovian boundary interval, ranging from Limestones I2 to K3. Both the conodont and fusuline faunas record the appearances in the basal part of the C25 (K) Suite of several new taxa that are more characteristic of the early Moscovian. These forms include Declinognathodus donetzianus at the top of K1 in conodonts and Eofusulina triangula, E. trianguliformis, and a large Neostaffella species (N. vozhgalica) at K2 in fusulines. Thus, the K1-K2 interval is very promising as the potential position of the formal Bashkirian-Moscovian boundary in the Donets Basin. The data from the Malonikolaevka section, together with those from other sections in the present study, would be significant for future investigations of the Task Group to establish a GSSP close to the existing Bashkirian-Moscovian Boundary organized in IUGS Subcommission on Carboniferous Stratigraphy (SCCS).

著者

柴田 賢

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.94, no.7, pp.682-686, 1986-01-25 (Released:2009-11-12)

参考文献数

10

著者

日野 文雄

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.50, no.2, pp.77-90, 1938-02-15 (Released:2010-10-13)

参考文献数

20

著者

日野 文雄

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.50, no.1, pp.19-30, 1938-01-15 (Released:2010-10-13)

著者

金田 楢太郎

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.5, no.4, pp.189-194, 1893-04-25 (Released:2010-10-13)

著者

David Simon

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.65, no.2, pp.100-105, 1956-06-30 (Released:2009-11-12)

参考文献数

1

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ソヴィエットの樺太および千島列島占領は, 以前の日本語の地名のあらゆる痕跡を拭い去つてしまつた。こんにちでは, 日本語の影響をほのめかす地名は, 一つとて存在しない。残されている地名はたゞアイズ語に起源をもつ, 若干のものであり, それらでさえも, ロシア当局によつて, 入念に篩にかけられた。ここに挙げたものは日本語の照合名, 地理的経緯度および地名起源の簡単な説明を加えた, 100の選択されたロシア語の地名である。

著者

湯田 ミノリ 伊藤 悟 内田 均 木津 吉永 伊東 純也

出版者

Tokyo Geographical Society

雑誌

地學雜誌 (ISSN:0022135X)

巻号頁・発行日

vol.117, no.2, pp.341-353, 2008-04-25

参考文献数

21

被引用文献数

2 4

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The use of GIS in education in Japan has not yet been widely diffused, although the computer and network environments of schools have been improved, and teachers have already recognized the characteristics and advantages of this tool in education.<br> Nowadays, GIS has been intergraded into many aspects of our lives. Mobile phones are also basic tools in our daily lives. A GIS application that runs on cellular phones would be helpful in school education.<br> From this point of view, the authors have developed a system called Cellular Phone GIS including a GIS application for mobile phone (hereinafter Cell Phone GIS Application) and its web-based GIS viewer application for PC using Google maps (hereinafter PC viewer), and carried out fieldwork at an upper secondary school using these tools. Data can be input and edited outdoors with the Cell Phone GIS Application. These data can be viewed on both cellular phones and personal computers via the Internet. Students carried out a land use survey in the area around the school with the Cell Phone GIS Application, and examined and presented the results using the PC viewer in class.<br> Students participated actively in the fieldwork with the cellular phone. Through experience of the survey with the tool, they found many new things and learned to adopt multi-dimensional points of view and ways of thinking. Also, this project generated more interest among students in geography classes.<br> The Cell Phone GIS Application provided high school students with a feeling of accomplishment from the fieldwork. Meanwhile, this tool and PC viewer minimized work after fieldwork because users do not have to input and aggregate data again. Therefore, teachers and students can use course hours efficiently. The Cellular Phone GIS can provide an environment in which students are able to receive educational effects from fieldwork.

著者

山本 真也 中村 高志 芹澤 如比古 中村 誠司 安田 泰輔 内山 高

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.129, no.5, pp.665-676, 2020-10-25 (Released:2020-11-13)

参考文献数

40

被引用文献数

3 5

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Lake bottom springs play an important role in maintaining water quality in the Fuji Five Lakes. However, the sources of these springs and the hydrological delivery mechanisms have yet to be identified. To determine the sources of spring water of Lake Kawaguchi, samples were collected directly from lake bottom springs, and oxygen and hydrogen stable isotope ratios were obtained, along with vanadium concentrations. Visual observations and water-quality analyses of the samples reveal that cold and oxygen-rich water is discharged from the lake floor, which is covered by gravel with diameters of 10-50 cm over an area of approximately 9 m (east–west) by about 13 m (north–south). The water temperature of the springs remained relatively constant at around 11.3°C during the stratified period in 2016; however, the temperature fluctuated significantly in 2017, even during the stratified period, suggesting a temporary decrease or stoppage of water being discharged from springs into the lake. Oxygen and hydrogen stable isotopic ratios of lake bottom springs were determined to be higher than those of groundwater in the southern part of Lake Kawaguchi; however, they displayed values close to those of groundwater in the northern part of Lake Kawaguchi, suggesting that spring water primarily originated from groundwater in the Misaka Mountains.

著者

高野 修 西村 瑞恵 藤井 哲哉 佐伯 龍男

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.118, no.5, pp.776-792, 2009-10-25 (Released:2010-03-19)

参考文献数

28

被引用文献数

21 18

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Since previous research revealed that most of the methane hydrates in the eastern Nankai Trough area occur in matrix pores of turbidite sandstones, the facies distribution of turbidite sandstones may be one of the important keys to evaluate the distributions and actual volume of methane hydrates in the eastern Nankai Trough area. This paper attempts to reconstruct depositional processes of submarine-fan turbidites, and examines the relationship between turbidite facies distributions and bottom simulating reflector (BSR) occurrence as a proxy of methane hydrate using sedimentologic and sequence stratigraphic methodology. First, 2D/3D seismic survey data and well data including cores and logs were used to identify turbidite facies, seismic facies, and depositional sequences. The targeted Plio-Pleistocene Kakegawa and Ogasa Groups can be divided into 17 depositional sequences, and include six seismic facies indicating submarine-fan elements and surrounding slope to basin-floor environments. Next, facies maps for each depositional sequence unit were created by plotting all information on seismic facies, 3D seismic geomorphology, and well facies data. The obtained facies maps reveal that 11 major submarine canyons functioned as positionally fixed sediment supply systems from main land Japan, along which submarine fans were formed in the forearc basins. Submarine-fan depositional styles changed through Plio-Pleistocene from a braided channel type, through small radial fan, trough-fill fan, and muddy sheet fan types, to a channel-levee system type. Finally, the facies maps of each depositional sequence were overlaid with the BSR distribution. The overlaid maps indicate that the BSRs occur on feeder channels, distributary channels, and proximal lobes of submarine fans, suggesting that methane hydrates selectively occur in coarser grained portions of a submarine fan. Because the lower part of the Kakegawa Group is mainly composed of braided channel-type submarine fan turbidites, the lower Kakegawa horizon serves one of the major horizons bearing methane hydrates in the eastern Nankai Trough area.

著者

池原 研

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.110, no.4, pp.471-478, 2001-08-25 (Released:2009-11-12)

参考文献数

23

被引用文献数

12 14

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Deep-sea turbidite has potential for paleoseismicity analysis. Many deep-sea turbidites were intercalated in two sediment cores collected from two slope basins off Tokai area along the eastern Nankai Trough. Geological and topographic setting of the basins suggests that these turbidites were of earthquake origin. Depositional age of each turbidite layer was determined by radiocarbon dating using planktonic foraminifera in hemipelagic mud. The results indicated that large earthquakes along the eastern Nankai Trough might have occur periodically every 100-150 years during the last 3000 years.

著者

小熊 宏之 井手 玲子 雨谷 教弘 浜田 崇

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.128, no.1, pp.93-104, 2019-02-25 (Released:2019-04-03)

参考文献数

18

被引用文献数

5 5

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The vulnerability of alpine ecosystems to climate change, as pointed out by the Intergovernmental Panel on Climate Change (IPCC), and the necessity to monitor alpine zones have been recognized globally. The Japanese alpine zone is characterized by extreme snowfall, and snowmelt time is a key factor in the growth of alpine vegetation. Therefore, in 2011, the National Institute for Environmental Studies (NIES), Japan, initiated long-term monitoring of snowmelt time and ecosystems in the Japanese alpine zone using automated digital time-lapse cameras. Twenty-nine monitoring sites are currently in operation. In this study, images from the cameras installed at mountain lodges in Nagano Prefecture and around Mt. Rishiri in Hokkaido are used. In addition, live camera images are obtained from cameras already operated by local governments in the Tohoku area and near Mt. Fuji. Red, green, and blue (RGB) digital numbers are derived from each pixel within the images. Snow-cover and snow-free pixels are classified automatically using a statistical discriminate analysis. Snowmelt time shows site-specific characteristics and yearly variations. It also reflects the local microtopography and differs among the habitats of various functional types of vegetation. The vegetation phenology is quantified using a vegetation index (green ratio) calculated from the RGB digital numbers. By analyzing temporal variations of the green ratio, local distributions of start and end dates and length of growing period are illustrated on a pixel base. The start of the green leaf period corresponds strongly to the snowmelt gradient, and the end of the green leaf period to vegetation type and elevation. The results suggest that the length of the green leaf period mainly corresponds to the snowmelt gradient in relation to local microtopography.

著者

宮本 真二

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.107, no.4, pp.535-541, 1998-08-25 (Released:2014-02-26)

著者

尾野 作次郎

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.51, no.12, pp.551-560, 1939-12-15 (Released:2010-10-13)

著者

小原 一成

出版者

公益社団法人 東京地学協会

雑誌

地學雜誌 (ISSN:0022135X)

巻号頁・発行日

vol.112, no.6, pp.837-849, 2003

被引用文献数

5 14

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Non-volcanic deep low-frequency tremors detected in southwest Japan are distributed in the forearc side along the strike of the descending Philippine Sea plate. The source depth of the tremor corresponds to the slab interface or the Moho discontinuity. The time sequence of the tremor activity is characterized by long durations from hours to weeks. The mobility and the successive occurrence of the tremor are thought to be related to the existence of fluid liberated from the slab by a dehydration process. The spatial distribution of the tremors is not homogeneous in a narrow belt but is spatially clustered. The major activity of the tremors with relatively long time durations is also clustered periodically, with a period of 2-3 months in the east and middle of Shikoku area and about 6 months in the west of Shikoku. On the other hand, tremors are sometimes triggered by local earthquakes or teleseismic waves. The periodicity of the tremor activity may represent a stable accumulation of fluid with a stable subduction process and the triggering phenomenon implies the unstable condition of the occurrence of tremors.

著者

鷺谷 威 大坪 誠

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.128, no.5, pp.689-705, 2019

被引用文献数

4

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<p> Geodetic estimates of crustal strain rates in the Japan islands were an order of magnitude larger than geological/geomorphological estimates, which has been an unresolved problem called the strain rate paradox. Ikeda (1996) postulated that geodetic strain mainly reflects elastic strain accumulation due to interactions at plate boundaries. This hypothesis was proven to be correct by the occurrence of the 2011 <i>M</i>_W 9.0 Tohoku-oki earthquake. Confusion between elastic strain and inelastic strain was the cause of the paradox. Significant postseismic deformation observed after the Tohoku-oki earthquake made it possible to distinguish the inelastic contribution from the geodetically observed crustal strain through a comparison with the pre-seismic strain rate pattern, which promoted a better understanding of inelastic deformation in the Japan islands. On the other hand, migration of localized deformation and temporal changes of strain rate are identified over a geological time scale, implying that it is essential to carefully review the methods and the uncertainties of geological/geomorphological strain rates. An integrated understanding of crustal deformation in the Japan islands is being advanced through detailed investigations of crustal strain rates on variable temporal and spatial scales.</p>

著者

星埜 由尚

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.129, no.2, pp.155-160, 2020

被引用文献数

3

著者

野間 三郎 門村 浩 中村 和郎 野沢 秀樹 堀 信行

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.83, no.2, pp.103-124, 1974-04-25 (Released:2010-02-25)

参考文献数

157

著者

野間 三郎 門村 浩 中村 和郎 野沢 秀樹 堀 信行

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.83, no.1, pp.19-37, 1974-02-25 (Released:2009-11-12)

被引用文献数

1

著者

奈須 紀幸

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.102, no.6, pp.645-663, 1993-12-05 (Released:2010-11-18)

参考文献数

19