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, 2019-10-25 (Released:2019-11-15)

参考文献数

63

被引用文献数

4 4

---

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 MW 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.

著者

竹之内 耕

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.125, no.6, pp.795-812, 2016-12-25 (Released:2017-01-25)

参考文献数

51

被引用文献数

4 4

---

Education on geopark activities is regarded to be a fundamental element for promoting sustainable development in local communities of the region. Implementation of school and social education on the Geopark Concept has progressed since the Global Geopark designation in 2009. In school education, a new education plan called the Unified Education Policy for Children Aged 0 through 18 was set up to promote geopark studies among schools in cooperation with the City Board of Education and the City Government. Having recognized the important role of Geoparks in school education, the City Board of Education has included geopark studies as a program within the compulsory education curriculum of subjects such as science, geography, and integrated studies. By following the education plan, the City Board of Education has continued to provide support to school teachers with the following results: outdoor and indoor training programs have been held by teachers' organizations and Itoigawa Geopark Council, showing educators how geoparks can be used in classroom education. Supplementary textbooks for grades 3 through 9 have been published and distributed, providing invaluable resources for the study of earth science and history, as well as regional culture. Citywide Geopark Studies Conferences have been held to give students opportunities to share what they have learned. An exchange program has been begun for elementary and junior high school students with Itoigawa's sister geopark in Hong Kong. In social education, new educational activities such as the Geopark Certification Exam for citizens, Geopark Guide Training Program, and Geopark Master Program linking businesses to the geopark have been set up by the Geopark Council. These educational systems have become popular among citizens, fostering pride in their hometowns and geoheritages, and related resources of global value. Based on that sense of pride, local residents have begun to promote regional development using geopark resources.

著者

遠藤 匡俊

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.611-634, 2020-10-25 (Released:2020-11-13)

参考文献数

63

被引用文献数

2

---

Natural phenomena such as volcanic eruptions, earthquakes, and tsunami, have long been regarded by many people around the world as indicating the wills of deities. Such superstitions have been replaced gradually by modern scientific thinking. The Ainu people believed that evil deities caused volcanic eruptions, so they prayed to benevolent deities in order to avert them. As such, the Ainu people had superstitious beliefs on the causes of volcanic eruptions and how they could be prevented. In spite of their superstitious beliefs, the Ainu people actually had scientifically accurate ideas on the process of a volcanic eruption, the origins of material ejected from a crater, and the process of lava dome formation. This was long before scientific conception of volcanology and the geomorphology of volcanoes emerged in Japan. Modern science was introduced to Japanese volcanology and the geomorphology of volcanoes in the 1890s. Around the 1791, the Ainu people, who were neither scientists nor specialists, surmised that a volcanic eruption was actually caused by burning material under ground rising up from a crater through a fire well to the surface. The Ainu people's deductions on the process of a volcanic eruption were similar to the latest theories on magma eruptions in volcanology. The Ainu people's course of action of seeking refuge when Mt. Usu erupted was not based on superstition but on their memories of past eruptions. These memories informed them that a series of earthquakes heralded an eruption, as well as the facts that damage to areas by eruptions and their personal sufferings were actually due to pyroclastic flows and surges from past eruptions of Mt. Usu.

著者

寺床 幸雄 梶田 真

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.125, no.4, pp.607-626, 2016

被引用文献数

2

---

 Minamata city is well known as the company town of Chisso Corporation, as the site of Minamata disease and, in recent times, as a city with environmentally friendly policies. The postwar experiences of Minamata city are often compared to a microcosm of Japanese modernization. A few decades earlier, the city faced and tackled several problems that most non-metropolitan cities currently face, such as an aging population and economic decline. There are meaningful lessons and suggestions we can adopt from Minamata city for sustainable development policies suited to non-metropolitan cities. This paper focuses on the economic history of Minamata (which includes not only Chisso but also other manufacturing companies and industries) and the dynamic relations between its local economy and politics. In Minamata, social tensions, such as those between the perpetrators and the victims of Minamata disease and between Chisso's labor and management, gradually disappeared due to reconciliation efforts and generational change. Minamata city office changed its vision of future development from being an industrial city to an environmentally friendly one, bearing in mind not only the experiences of Minamata disease victims but also the city's varied environmental resources. The residents of Minamata offered their support for these policies in recent mayor elections. Nevertheless, new problems began to emerge in the city. Jobs for the young had been limited for a long time, especially for men and those who were highly educated. One of the reasons for this is that Chisso prioritized retaining employees and restricted new hiring. Besides, the economic dominance of Chisso prevented local leaders and enterprises from growing. As a result, although Minamata's town planning, with its emphasis on environmentally friendly policies, received much attention and support, those policies could not be effectively implemented due to a lack of local human and institutional resources. Recently, however, young residents have begun to construct new social networks. It is worth noting that they share environmentally friendly visions. We can regard these kinds of movement as the results of continued efforts by Minamata city office and citizens. The economic and social dynamics of Minamata and the problems mentioned here are likely to be common to many non-metropolitan cities. Those cities must not be nearsighted about depopulation problems, but should investigate and try to maintain the conditions needed for long-term social and economic sustainability.

著者

大森 房吉

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.32, no.3, pp.116-124, 1920-03-15 (Released:2010-10-13)

著者

山本 純之 磯﨑 行雄

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.122, no.5, pp.791-806, 2013

---

&emsp;Ever since the term stromatolith was first coined by Kalkowsky in 1908, research studies on stromatolites have continued for more than a century. This article reviews the study history of living and fossil stromatotelites. The history is divided into two parts by the discovery in 1961 by Logan of living stromatolites in Shark Bay, Western Australia, because this determined the subsequent main trend of studies on both living and fossil stromatolites. Major contributions during the last three decades include documentation of (1) a worldwide bloom of stromatolites in Proterozoic low-middle lateral shallow seas, and (2) oxygen-producing cyanobacterial activity related to stromatolites from the 1990s, resulting in various new aspects being clarified, which include <i>in-vitro</i> cultivation gradually revealing cyanobacterial calcification and dome-formation. Future studies will be directed towards reconciling morphological disparities and formation mechanisms among fossil, living, and cultured stromatolites.

著者

山口 寿之

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.86, no.5, pp.285-304, 1977-10-25 (Released:2009-11-12)

参考文献数

50

---

The phylogeny of Cirripedia has been studied by DARWIN (1851 a, b, 1854 a), BROCH (1922), WITHERS (1928, 1935, 1953) and others. Their discussion on the phylogeny has mainly concentrated upon an order Thoracica which has abundant fossil records. There is a consensus of opinion that three suborders of order Thoracica, Verrucomorpha, Brachylepadomorpha and Balanomorpha, independently derived from the Scalpellidae of suborder Lepadomorpha. In the phylogeny of Lepadomorpha, however, two different opinions have been proposed on evaluation of primitiveness of the Scalpellidae (s. lat.) and the Lepadidae (s. lat.). DARWIN, WITHERS and others interpreted that the Scalpellidae is more primitive than the Lepadidae. While BROCH considered that the Scalpellidae is as primitive as the Lepadidae. For this twenty years many new data on ontogeny, nervous system, sexuality, shell structure, ecology and Paleozoic fossil records were accumulated for interpretation of the phylogeny of lepadomorph cirripeds. NEWMAN, ZULLO and WITHERS (1969) have proposed a new interpretation on the phylogeny of Cirripedia based on these data. In this report these works are reviewed and evaluated.

著者

寺床 幸雄 梶田 真

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.125, no.4, pp.607-626, 2016-08-25 (Released:2016-09-12)

参考文献数

21

被引用文献数

3 2

---

Minamata city is well known as the company town of Chisso Corporation, as the site of Minamata disease and, in recent times, as a city with environmentally friendly policies. The postwar experiences of Minamata city are often compared to a microcosm of Japanese modernization. A few decades earlier, the city faced and tackled several problems that most non-metropolitan cities currently face, such as an aging population and economic decline. There are meaningful lessons and suggestions we can adopt from Minamata city for sustainable development policies suited to non-metropolitan cities. This paper focuses on the economic history of Minamata (which includes not only Chisso but also other manufacturing companies and industries) and the dynamic relations between its local economy and politics. In Minamata, social tensions, such as those between the perpetrators and the victims of Minamata disease and between Chisso's labor and management, gradually disappeared due to reconciliation efforts and generational change. Minamata city office changed its vision of future development from being an industrial city to an environmentally friendly one, bearing in mind not only the experiences of Minamata disease victims but also the city's varied environmental resources. The residents of Minamata offered their support for these policies in recent mayor elections. Nevertheless, new problems began to emerge in the city. Jobs for the young had been limited for a long time, especially for men and those who were highly educated. One of the reasons for this is that Chisso prioritized retaining employees and restricted new hiring. Besides, the economic dominance of Chisso prevented local leaders and enterprises from growing. As a result, although Minamata's town planning, with its emphasis on environmentally friendly policies, received much attention and support, those policies could not be effectively implemented due to a lack of local human and institutional resources. Recently, however, young residents have begun to construct new social networks. It is worth noting that they share environmentally friendly visions. We can regard these kinds of movement as the results of continued efforts by Minamata city office and citizens. The economic and social dynamics of Minamata and the problems mentioned here are likely to be common to many non-metropolitan cities. Those cities must not be nearsighted about depopulation problems, but should investigate and try to maintain the conditions needed for long-term social and economic sustainability.

著者

片岡 龍峰

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.119, no.3, pp.519-526, 2010-06-25 (Released:2010-08-30)

参考文献数

16

被引用文献数

1 1

---

Possible influences of cosmic rays on terrestrial climate have been studied by many researchers since a good correlation between neutron monitor counts and global cloud amount was reported by Svensmark and Friis-Christensen in 1997. The cosmic ray-cloud relationship may be best tested during Forbush decrease events, in which cosmic rays largely decrease for several days associated with coronal mass ejections. Some cloud parameters are likely to respond to the transient decrease of cosmic rays with a typical time delay of several days, although we do not know the physics behind the cosmic-ray cloud relationship.

著者

早坂 一郎

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.38, no.2, pp.55-65_1, 1926-02-15 (Released:2010-10-13)

被引用文献数

2

著者

今岡 照喜 秋田 幸穂 永嶌 真理子

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.130, no.3, pp.369-378, 2021-06-25 (Released:2021-07-20)

参考文献数

34

被引用文献数

3

---

愛媛県岩城島の白亜紀エジリンアルビタイトより稀なK–Zr珪酸塩鉱物であるデーリー石とLi–Na–Zr珪酸塩鉱物であるゼッツェル石が見いだされた。デーリー石とゼッツェル石のEPMA分析結果からそれぞれ(K1.93Ba0.01)Σ1.94(Zr0.99Hf0.02)Σ1.01Si5.98O15およびNa1.03(Zr0.96Hf0.02Y0.01Sc0.01)Σ1.00Li1.02(Si5.95Al0.04)Σ5.99O15の実験式が得られる。多孔質ジルコン,デーリー石,および不安定なジルコンを被覆するゼッツェル石の産状から,このアルビタイトは熱水活動時期におけるNa,K,Liに富んだ流体によるジルコニウム鉱物の分解と沈殿による交代反応の記録をよく保存している。これは日本列島におけるデーリー石とゼッツェル石産出の最初の報告である。

著者

松岡 憲知 池田 敦

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.2, pp.269-305, 2012-04-25 (Released:2012-05-29)

参考文献数

283

被引用文献数

6 4

---

Periglacial process studies, which began in the mid-20th century, have greatly advanced in recent years following several breakthroughs. This paper reviews the latest breakthroughs supported by new technologies, themes, and international projects. New technologies have enabled small, high-resolution data loggers to monitor rock and soil movements, and thermal and hydrological properties in polar and alpine areas; enabled geophysical instruments to visualize two- and three- dimensional subsurface structures below periglacial features; and, enabled numerical simulations to predict future landform evolution. In particular, dramatic progress has been achieved in understanding bedrock shattering and falls, soil movements induced by freeze-thaw oscillations, controls on rock glacier creep, critical conditions for ice-wedge cracking, and biogeophysical impacts on non-sorted circles. Two key words, global warming and Mars, are appearing often in periglacial research. High mountains and polar lowlands face the fate of potential natural hazards associated with rock slides, debris flows and thermokarst subsidence, possibly originating from permafrost thawing. High-resolution orbital images and on-site explorations on Mars provide detailed information on small-scale, potential periglacial features, which are the morphologically equivalent of terrestrial counterparts. International collaboration is expected to further promote modeling various periglacial features on a global scale, improve the resolutions of periglacial climate indicators, and increase understanding of past and present Martian environments.

著者

高橋 成実 小平 秀一 佐藤 壮 山下 幹也 海宝 由佳 三浦 誠一 野 徹雄 瀧澤 薫 野口 直人 下村 典夫 金田 義行

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.124, no.5, pp.813-827, 2015-10-25 (Released:2015-11-04)

参考文献数

52

被引用文献数

6 8

---

Japan Agency for Marine-Earth Science and Technology carried out seismic surveys using ocean bottom seismographs (OBSs) and a multi-channel reflection survey system from 2004 to understand the structural characteristics and the continuity of the Izu–Ogasawara Arc crust. The Izu–Ogasawara Arc developed from the oceanic crust and produced andesitic middle crusts. The velocity is similar to that identified in the continental crust, and the initial continental crust might have been produced during development of the arc crust. To investigate the process of the Izu–Ogasawara Arc crust, many 2-D velocity structures are compared using unified specifications of data acquisition and analysis, and structural commonalities and differences are evaluated. The specification was confirmed previously through simulation studies using the structure obtained. These arc crustal structures have common characteristics, which are an upper crust with a Vp of 4.5–6.0 km/s, a middle crust with a Vp of 6.0–6.5 km/s, and a lower crust with a Vp of 6.5–7.5 km/s. The lower crust is composed of two layers; the upper part has a Vp of 6.5–6.8 km/s and the lower part has a Vp of 6.8–7.5 km/s. The uppermost mantle has a Vp of less than 8.0 km/s. Development of the arc crust results in crustal thickening accompanied by rifting. Back arc opening after rifting plays the role of crustal thinning. The Shikoku Basin, which is the older backarc basin, has a relatively thin crust with a thickness of approximately 10 km, and the eastern part has a high velocity lower crust with a Vp of over 7 km/s. In addition, the upper crust of the eastern part of the Shikoku Basin has some intrusive materials and strike slip faults with few vertical displacements. Such a high-velocity lower crust is not distributed in the Parece Vela basin. The Ogasawara Ridge has different characteristics from the above arc crust, which are a crustal thickness of approximately 20 km but a complicated structure including a narrow and thin crust in the N–S direction. Here, we introduce the structural characteristics of the entire Izu–Ogasawara Arc crusts based on unified seismic surveys and data analysis methods.

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.15, no.1, pp.95a-95a, 1903

著者

増田 富士雄

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.114, no.3, pp.419-433, 2005-12-25 (Released:2009-11-12)

参考文献数

67

---

A new research field is introduced for strata science in geology. The new stratigraphy is that a layer, a bed and/or a band of “a year, a month, a day, and several hours” we actually experience everyday, are defined from strata. In this paper we introduce the following four case studies of high-resolution determination for 1) annual beds, 2) historical river-flooding beds, 3) tidal bands, and 4) cross-beds. We also describe new information obtained from the results of these high-resolution stratigraphic studies, which include : discovery of millennial oscillations of solar cycle from the 500 Ka lake varves (annual beds) date determination of every fluvial-flooding beds from the intercalated human wastes and, 600-million-year history of Earth's rotation detected from an annual band in fossils and tidal beds in strata.

著者

町田 尚久

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.123, no.3, pp.363-377, 2014-06-25 (Released:2014-07-03)

参考文献数

31

被引用文献数

1

---

To clarify the cause of heavy rains and weather related to a famous disaster that occurred in 1742, the weather sequence and its spatial distribution were investigated on the basis of local historical documents obtained from various areas of central Japan. As a result, the eastward movement of a typhoon was reconstructed in the sea off the south coast of central Japan. It was accompanied by an inflow of moist air around the eastern fringe of the typhoon, which brought about a rain zone extending from Kinki to Kanto from 27th Jul. to 1st Aug., according to the lunar calendar used at that time. The typhoon abruptly turned north when it reached southern Kanto and proceeded north across Honshu. It was accompanied by heavy rains and strong winds on 1st and 2nd Aug., which were recorded in central and western Kanto and areas further north. The abrupt change of direction seems to have been caused by a strong anticyclone that is thought to have extended to the east coast of Kanto. Although this situation around an anticyclone occurs frequently in late Summer, not enough evidence has been obtained yet on the situation at that time. The heavy rains and induced landslides caused floods particularly in the Ara, Tone, and Chikuma river basins. This is a matter of concern from the viewpoint of a fluvial geomorphic system analysis.

著者

小山 真人

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.104, no.1, pp.45-68, 1995-02-25 (Released:2010-11-18)

参考文献数

84

被引用文献数

3 5

---

A multi-disciplinary synthesis was made on the tectonics and seismotectonics in the northwestern Sagami Bay and adjacent areas, where the plate boundary between the Izu-Bonin and Northeast Japan arcs passes and historical M7-8 inter-and intraplate earthquakes frequentlyhave occurred.In a convergent boundary between plates, a displacement between plates is usually accommodatedalong a broad belt of active imbricated thrusts and folds, which develop in a wedge ofan overriding plate. In such a situation, we can easily identify two kinds of plate boundaries: a deformation front and a subduction entrance. The deformation front is a line connecting thethrusts or folds nearest to a trench/trough axis. The subduction entrance is a line connecting theedges of trench/trough filling coarse deposits, which cover a surface of a subducting plate. In Sagami Bay, the deformation front in the overriding Northeast Japan arc is estimated to belocated along the northern and eastern edges of the Sagami Basin, while the subductionentrance of the subducting Izu-Bonin arc is estimated to be located along the southern edge of the Basin.Many geomorphological, geological, geophysical observations need and support the existenceof the West Sagami Bay Fracture (WSBF), an intraplate propagating fracture between the Izu-Bonin outer and inner arcs, proposed by Ishibashi (1988), whereas these observations require slightmodification of the estimated geometry around the WSBF. Frequent dike intrusions in theHigashi Izu monogenetic volcano field cause spreading of the upper crust and probably move the Manazuru “microplate”(MNZ) to the NNE direction against the Izu block. The Tanna-Hirayama tectonic line is proposed as a transform fault, which accomodates the relativemovement between the MNZ and the Izu block. In the MNZ hypothesis, the Kozu-Matsuda fault, located to the northeast of the Izu Peninsula, is interpreted as a deformation front between theoverriding Northeast Japan arc and the MNZ, which is buoyantly subducting beneath the Oiso Hilland Tanzawa Mountains. The proposed new geometry around the WSBF and the hypothesis of the MNZ can explain (1) the crustal structure and tectonic features around the Kozu-Matsudafault, (2) tectonic implication of the “Oiso-type” earthquakes, which are expected to displacethe Kozu-Matsuda fault periodically, and (3) the rapid upheaval of the Tanzawa Mountains since 1Ma.

著者

山崎 直方

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.17, no.1, pp.5-20_2, 1905-01-15 (Released:2010-10-13)

著者

佐藤 昌人 八反地 剛 松岡 憲知

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.125, no.1, pp.133-153, 2016-02-25 (Released:2016-03-22)

参考文献数

168

被引用文献数

4 3

---

Weathering processes on Martian surface are among the essential issues for both understanding landform evolution and exploring water availability on Martian surface. Studies are reviewed on various weathering processes on Martian surface based on images, data collected by rovers, and laboratory approaches. Recent explorations by the Mars Exploration Rovers reveal that chemical weathering occurs on the surface of basaltic regolith. Dissolution of olivine and oxidation of Fe produces weathering rinds on basaltic surface regolith. Rock interiors also show vugs and veins filled with light-toned efflorescence indicative of chemical weathering. In particular, in high-latitude areas the two Viking landers and the Mars Pathfinder observed honeycomb weathering, angular rock fragments, and polygonal cracks in bedrock. Most of these features are also observed in the Antarctica and other cold deserts on Earth, and are generally attributed to physical weathering such as salt crystallization, thermal weathering, and/or frost weathering. Some studies successfully estimate periods and rates of weathering on the Martian surface, which promote a further understanding of environmental changes and landform evolution.

著者

矢島 道子

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.114, no.4, pp.609-613, 2005-12-25 (Released:2009-11-12)

参考文献数

6