著者
宮井 宏
出版者
Tokyo Geographical Society
雑誌
地学雑誌 (ISSN:0022135X)
巻号頁・発行日
vol.108, no.3, pp.231-247, 1999-06-25 (Released:2010-10-13)
参考文献数
11

Meteorological observations have been made since 1881 by a weather station in Kyoto, Japan. Therefore, some approach must be considered to know about tempe ratures before 1881. This paper gives quantitative estimates of the monthly mean of the lowest daily temperature in winter in Kyoto.A long record of dates Lake Suwa, in central Japan, 36°N138°E, 250km from Kyoto, was frozen has been found in the Suwa Shrine Documents by S. Fujiwara and collected by H. Arakawa.A long record of dates of snowfalls was extracted by the author from many old diaries kept in Kyoto.The dates Lake Suwa froze and the first and the last dates of snowfalls in Kyoto bet ween 1881 and 1953 are correlated with the monthly mean of the lowest daily temperature in winter observed in Kyoto. The correlations obtained are applied to estimate winter temperatures in Kyoto before 1881.As a result, two series of winter temperatures are obtained: one deduced from the freezing dates and the other from the dates of snowfalls. The former covers 430 years (1450-1880) and the latter 880 years (1001-1880).The two series give almost identical winter temperatures considering the error involved in the correlation used and the volume of available snowfalling data.The sequence of the 50-year means of temperature obtained from the dates the lake was frozen shows that the mean lowest daily winter (December-March) temperature has been rising incrementally from-0.7°C in 1551 to-0.2°C in 1880.The sequence of the 100-year means of temperature obtained from the dates of snowfalls shows that the mean of the lowest daily winter (December-March) temperature from the year 1101 to 1200 was higher by 0.8°C than one from the year 1001 to 1880.
著者
坂上 澄夫 八田 明夫
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.99, no.3, pp.230-246, 1990
被引用文献数
1

Recently we had chance to visit Palau Islands two times in 1986 and 1988. The aim of the present article is to introduce the geology including some new evidences investigated by us, and the human history of the islands is also briefly described.<BR>The Aimeliik volcaniclastic rocks, which have been recognized as in the Eocene Aimeliik (=Aimiriki) Formation by the former scientists, from the quarry at Ngeruluobel located at about 1km west of the Palau International Airport terminal at Airai in southern end of Babelthuap Island, are discussed in Cepter V. Many foraminifers, calcareous algae and some corals were found as individuals in the matrix or in the limestone gravels of the volcaniclastic rocks. Among the determinable species of foraminifers, <I>Biplanispira absurda, B, inflata, B. mirabilis, Pellatispira rutteni, Fabiania saipanensis</I> and <I>Discocyclina dispansa</I> were reported from the Matansa Limestone (Upper Eocene) of Saipan, and <I>Gypsina globulus, Eulepidina formosa</I> from the Tagpochau Limestone (Lower Miocene) of Saipan by HANZAWA (1957). It seems there are at least two groups of foraminiferal fauna showing different ages, namely, the Upper Eocene and Lower Miocene (Aquitanian to Burdegalian). Accordingly, the depositional age of the Aimeliik volcaniclastic rocks should be Late Miocene or later.<BR>In Chapter VI, we introduce our study (SAKAGAMI <I>et al</I>., 1987) on the environmental change in some period of the Miocene to Pliocene by the pollen and spore analyses of the Airai lignite-bearing beds in Babelthuap Island.<BR>Lastly the literatures on geological sciences are comprehensively compiled for the convenience to the future study.
著者
丸山 茂徳
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.6, pp.1090-1106, 2012-12-25 (Released:2013-01-07)
参考文献数
52

The geotectonic division of the Japanese islands has been proposed by Isozaki and Maruyama (1991) such that the eastern extension of the Dabie-Sulu 240-220 Ma collisional UHP-HP belt (DSB) passes through the Korean peninsula to Japan. The corresponding belt in Japan is the Higo-Unazuki-Hitachi-Takanuki belt (HUHTB), because the protoliths are a unique A-type (platform sediments) and the metamorphic facies series belongs to the intermediate-pressure type, in addition to 240-220 Ma of metamorphic ages. Ishiwatari and Tsujimori (2012) claim that Maruyama et al. (2011) did not evaluate a new proposal by Ishiwatri and Tsujimori (2003), who proposed that the DSB extends not to the HUHTB but to the Sangun belt in a complex manner because of the promontory nature of the continental margin. This is a Q-A report requested by Ishiwatari and Tsujimori (2012). In this paper the author first introduces a classification of orogenic belts based on protoliths and its great significance for understanding the history of complex orogenic belts, following the original article by Maruyama et al. (1996), in addition to current topics on the role of tectonic erosion. Preceding the final formation of the collisional orogen, the Pacific-type orogen must have been present structurally above the collisional orogen against the hanging wall of the continent or arc. If not, it suggests the presence of tectonic erosion. Moreover, the size of any of regional metamorphic belt, arc, and TTG belt could be an excellent indicator of the scale of tectonic erosion. The Triassic DSB continues not to Sangun belt, but to the HUHTB, for four reasons: first, the protolith of those belts, second; the nature of regional metamorphism along intermediate-pressure type; third, structural units above and below the HUHTB; and finally, paleogeographic reconstruction of the Triassic North and South China cratons. The tectonic juxtapositions of the four so-called Sangun BS belts —450 Ma, 340 Ma, 250-210 Ma, and 170-180 Ma— against the HUHTB in a narrow zone as klippes can best be interpreted by extensive tectonic erosion.
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.227-240, 2020
被引用文献数
4

<p> The map of Japan drafted by Inoh Tadataka is considered to be the earliest produced from a scientific survey. The descriptions of longitude and latitude are based on astronomical observations, and Inoh's nationwide survey has been considered to be the origin of modern surveys in Japan. However, he did not succeed in determining longitude. Although he had knowledge of a spherical earth, the results of his survey were projected on a plane, not on a spherical surface. The parallels of latitude drawn on his maps are based on an accurate astronomical survey he carried out, but the meridians on his maps are absolutely inconsistent. His survey method also combined traverse and intersection surveys without control points. Therefore, his nationwide survey cannot be considered to be representative of a survey carried out in the modern period. There are many open traverse lines on his maps. These lines generally extend to temples and shrines, although they are not effective for improving the accuracy of the survey. Because temples and shrines might have been important public facilities at that time, the Tokugawa shogunate government probably requested information concerning their locations. He carried out a nationwide survey ten times, but he could not survey the northern half of Ezo island (Hokkaido). It is said that Mamiya Rinzo, who studied survey technology under Inoh Tadataka, surveyed Ezo island and submitted his survey data to Inoh Tadataka, therefore, Inoh's map of Ezo island might be entirely based on Mamiya's data. Further studies are necessary because Mamiya's survey has not been clarified.</p>
著者
坂上 澄夫 八田 明夫
出版者
Tokyo Geographical Society
雑誌
地学雑誌 (ISSN:0022135X)
巻号頁・発行日
vol.99, no.3, pp.230-246, 1990-06-25 (Released:2009-11-12)
参考文献数
99

Recently we had chance to visit Palau Islands two times in 1986 and 1988. The aim of the present article is to introduce the geology including some new evidences investigated by us, and the human history of the islands is also briefly described.The Aimeliik volcaniclastic rocks, which have been recognized as in the Eocene Aimeliik (=Aimiriki) Formation by the former scientists, from the quarry at Ngeruluobel located at about 1km west of the Palau International Airport terminal at Airai in southern end of Babelthuap Island, are discussed in Cepter V. Many foraminifers, calcareous algae and some corals were found as individuals in the matrix or in the limestone gravels of the volcaniclastic rocks. Among the determinable species of foraminifers, Biplanispira absurda, B, inflata, B. mirabilis, Pellatispira rutteni, Fabiania saipanensis and Discocyclina dispansa were reported from the Matansa Limestone (Upper Eocene) of Saipan, and Gypsina globulus, Eulepidina formosa from the Tagpochau Limestone (Lower Miocene) of Saipan by HANZAWA (1957). It seems there are at least two groups of foraminiferal fauna showing different ages, namely, the Upper Eocene and Lower Miocene (Aquitanian to Burdegalian). Accordingly, the depositional age of the Aimeliik volcaniclastic rocks should be Late Miocene or later.In Chapter VI, we introduce our study (SAKAGAMI et al., 1987) on the environmental change in some period of the Miocene to Pliocene by the pollen and spore analyses of the Airai lignite-bearing beds in Babelthuap Island.Lastly the literatures on geological sciences are comprehensively compiled for the convenience to the future study.
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
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
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.