著者

新井 智一

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.4, pp.676-691, 2011-08-25 (Released:2011-11-10)

参考文献数

22

被引用文献数

3 2

---

This paper discusses locational conflicts surrounding a new waste disposal facility in Koganei City from the viewpoint of “the politics of scale”. Since 1957, Koganei, Chofu, and Fuchu cities have disposed of their waste at Nimaibashi Waste Disposal Facility. In 2007, Koganei City officials proposed the construction of a new facility by 2017 at the site of the Nimaibashi Waste Disposal Facility, which was located at the periphery of Koganei City, or at the site of a former Janome sewing machine factory, which was located at the center of the city. Although people residing near both sites protested against the construction of the new facility, the Koganei City officials decided to construct the new facility at the site of the Nimaibashi Waste Disposal Facility. The reason for this decision is summarized as follows: (1) Most of the citizens of Koganei City appeared to be indifferent to this locational conflict; (2) The Koganei City officials were adamant about constructing an incineration facility; (3) The actions of the people residing near the former Janome sewing factory, unlike those of the people residing near Nimaibashi Waste Disposal Facility, were successful in protesting given the scale of Koganei City.

著者

遠藤毅

出版者

東京地学協会

雑誌

地学雑誌

巻号頁・発行日

vol.113, no.6, 2004

著者

渡辺 武男

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.73, no.2, pp.125-128, 1964-04-30 (Released:2009-11-12)

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.6, no.9, pp.520b-520b, 1894

著者

野口 里奈 栗田 敬

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.35-48, 2016-02-25 (Released:2016-03-22)

参考文献数

71

被引用文献数

3 6

---

Cone morphologies with a variety of origins and sizes have been widely identified on Mars using remote sensing data such as ultra-high resolution visible images. Currently, small cones of less than 100 m in bottom diameter can be identified. These Martian cones are located in young surface regions, suggesting they were produced in an environment that existed in recent geological history. They had volcanic, periglacial, and other origins. This paper first introduces a classification of terrestrial cone morphology: volcanic (spatter cones, scoria/pumice cones, maars, tuff rings, tuff cones, and rootless cones), periglacial (pingos), and others (mud volcanoes). Then, it reviews the characteristics of cone morphology on Mars focusing on morphology, morphometry, and distribution. Previous cone studies show the existence of explosive basaltic eruptions on recent Mars, while young lava flows were pervasive. The prevalence of rootless cones suggests the presence of water/ice during their formation at many places on Mars. These discoveries contribute to clarifying the recent surface environment and thermal state of Mars. To further apply terrestrial knowledge to Martian cones, it is necessary to understand the relationship between the morphology and the formation process of cone morphologies on Earth from a wide perspective.

著者

遠藤 匡俊

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.113, no.3, pp.421-424, 2004-04-25 (Released:2009-11-12)

著者

松田 博貴

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.2, pp.297-308, 2009-04-25 (Released:2010-04-01)

参考文献数

34

被引用文献数

3 4

---

Dolomite (dolostone) is a common carbonate rock in the geological records and is also a very important carbonate reservoir rock, which stock about 40% of global oil reserves. Most of the dolomites in the geological record are considered to be of replacement origin, although some were precipitated directly from pore-fluids. A variety of dolomitization models in different diagenetic environments are currently proposed for interpreting ancient dolomites: (1) evaporative dolomitization including sabkha and seepage-reflux models, (2) mixed-water dolomitization, (3) marine dolomitization, (4) burial dolomitization, (5) hydrothermal dolomitization. The dolomites formed by each dolomitization model have different geological, petrographical, mineralogical and geochemical features. Based on these features, we can, therefore, identify dolomitization models and diagenetic environments of ancient dolomites. A dolomite reservoir is often of as good quality as a limestone reservoir. Dolomitization affects carbonate reservoir characteristics, such as porosity and permeability, and, as a result, reservoir characteristics are significantly changed from those of primary carbonate rocks. The important factors associated with dolomitization and controlling the characteristics of carbonate reservoir rocks are: (1) increasing crystal size (2) decreasing porosity due to a net addition of dolomite, (3) developing moldic pores, (4) increasing resistance to compaction, and (5) increasing fractures. Dolomitization and diagenetic history of individual carbonate reservoirs differ from each other and result in the complexity of reservoir characteristics. It is, therefore, indispensable to understand the processes that formed each dolomite reservoir.

著者

鳴海 一成 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.128, no.4, pp.649-665, 2019-08-25 (Released:2019-09-20)

参考文献数

104

被引用文献数

2 3

---

Natural ionizing radiation, which potentially affects biota inhabiting the Earth, can be broadly divided into two types according to origin: cosmic radiation and subsurface radiation. Cosmic radiation contains galactic cosmic rays and solar energetic particles. Subsurface radiation is derived from radionuclides such as uranium, thorium, and radon. The levels of these forms of natural radiation were not constant temporally and spatially, and underwent a lot of changes in the early Earth environment. However, the ground level radiation dose rate of secondary muons derived from a supernova event that causes the most severe biological effects among forms of cosmic radiation is estimated to be 1 sievert (Sv) per year at most, which is too low to have lethal and mutagenic effects on terrestrial microbes. On the other hand, a nuclear fission chain reaction occurred in Oklo uranium ore deposit in Gabon about 2 billion years ago and continued intermittently for 105-106 years. The average total radiation dose rate of a typical natural fission reactor in Oklo is estimated to be 47.4 Sv per hour. This value is high enough to serve as a physical mutagen for subsurface microbes inhabiting areas near the reactor, and a million years is long enough to generate a new species of microbes. The observed growth-inhibitory critical dose rate for Escherichia coli is estimated to be 36 to 67 Gy per hour. On the other hand, the radioresistant bacterium Deinococcus radiodurans is shown to be cultivated without any growth delay at up to 126 to 180 Gy per hour of gamma rays. Recent EXAFS and isotopic analyses indicate that biogenic processes are more important for uranium ore genesis than previously understood. D. radiodurans and its closely related species Thermus thermophilus are shown to have the ability to reduce U(VI) to U(IV) under anaerobic conditions. These lines of evidence suggest that a common ancestor of Deinococcus and Thermus might be involved in the formation process of Oklo uranium ore deposit. Therefore, the radiation dose rate at Oklo-type natural nuclear reactors would be suitable for affecting the growth of microbes and generating genome evolution through accumulated mutations.

著者

柏木 洋彦

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.126, no.4, pp.513-531, 2017-08-20 (Released:2017-09-27)

参考文献数

86

被引用文献数

2 2

---

Weathering is deeply related to global climate change. In the carbon cycle, silicate weathering, especially volcanic rock weathering, transfers carbon in the atmosphere (as CO2) to the lithosphere, and oxidative weathering of organic matter releases carbon (as CO2) from the biosphere to the atmosphere. Moreover, as an indirect effect of weathering on climate change, negative feedback in the climate system, which results from the dependence of weathering rate on temperature and evolution of terrestrial plants, is crucial. It has stabilized the long-term global climate throughout the Phanerozoic. Weathering rate is controlled by several geochemical external factors: tectonic forces such as lithology, continental uplift, and continental drift (paleogeography); climate forces such as temperature, runoff, and glaciations; and, biological forces such as terrestrial plant evolution. Regarding biological forces, accelerated weathering assisted by ectomycorrhizal fungi (EM fungi) and arbuscular mycorrhizal fungi (AM fungi), as well as vascular plants of gymnosperms and angiosperm, are emphasized. Variations of global weathering in the geological past are estimated using experimental approaches, such as isotope analysis (e.g., 87Sr/86Sr, 187Os/186Os, δ7Li), and theoretical approaches, such as numerical simulations (e.g., carbon cycle model). Each is used differently according the purpose of a study. Based on these estimates, geological past climate changes in the Phanerozoic are found to be closely related to weathering. For example, on the order of magnitude of 107 years, changes in weathering patterns due to continental drift (paleogeography) have resulted in variations of atmospheric CO2, hence climate change. On the order of magnitude of 106 years, it is suggested that a decrease in atmospheric CO2 from the mid- to late Cretaceous was caused by enhanced weathering according to terrestrial plant evolution and that variations of atmospheric CO2 in the late Cenozoic were regulated by weathering directly or indirectly influenced by continental uplift. Additionally, contributions of weathering to global climate change involved in oceanic anoxic events in the Mesozoic have been investigated.

著者

高野 武男 関田山脈団体研究グループ

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.901-918, 2008-10-25 (Released:2010-04-27)

参考文献数

49

---

We studied the morphogenetic movements associated with the formation of the Sekita Mountains and Iiyama Basin situated at the boundary between the Niigata and Nagano prefectures in central Japan. As a result, we obtained following conclusions. (1) The morphogenetic movement of the Sekita Mountains is a semicylindrical upwarping originating from faulting at both sides of the mountains. The origin was an inclined thrust of a basal block. In addition, it is assumed that the upheaval of the mountains due to a change in isostasy caused by erosion resulted in the four-thousand meter thick strata that constitutes the mountains, and erosion originated from a fold in the strata occurring in the middle Pleistocene. (2) The morphogenetic movement constituting the Iiyama Basin is a reverse fault, which originated from tilting and drawing of the basal crust as a result of a semicylindrical upwarping of the Kato Mountains situated at the east side of the Iiyama Basin. The upwarping was caused by magma ascending from a deep part of the crust. Therefore, the Iiyama Basin was formed as a fault-angle basin. The mountain body of Kenasi Volcano tilted toward the west through the process of forming the Iiyama Basin. We think the Iiyama Basin continued to subside at the rate of about one millimeter a year in the Holocene, based on radiocarbon dating of drilling core samples collected from sediments in the alluvial lowlands.

著者

藤原 義弘

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.112, no.2, pp.302-308, 2003-04-25 (Released:2009-11-12)

参考文献数

23

被引用文献数

4 5

---

The bacterial endosymbionts of the solemyid clam Acharax johnsoni and the thyasirid clam Parathyasira kaireiae, collected from the Japan Trench, were characterized. Transmission electron microscopic observations showed numerous bacteria in the epithelial cells of the gill tissues of A. johnsoni. Numerous bacteria were also visible in the gill tissues of P. kaireiae, but were not located within the epithelial cells. Phylogenetic analysis based on the 16S ribosomal RNA gene sequences from the gill tissues of both clams indicated that the bacteria were related to sulfur-oxidizing endosymbionts from deep-sea chemosynthetic environments. The symbiont of A. johnsoni formed a monophyletic group with the thioautotrophic symbiont of Solemya reidi, which lives relatively deeper than other solemyid clams. The symbiont of P. kaireiae formed a monophyletic group with symbiont II in Maorithyas hadalis, which lives in the hadal zone of the Japan Trench. In addition, four vesicomyid species living relatively deeper than other vesicomyid clams also have a specific clade of thioautotrophic symbionts. Bacterial chemotrophic endosymbionts as well as the mode of symbiosis might influence host distributions in deep-sea chemosynthetic ecosystems.

著者

斎藤 成也

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.111, no.6, pp.832-839, 2002-12-25 (Released:2009-11-12)

参考文献数

12

被引用文献数

1

著者

脇水 鐵五郎 近藤 會次郎

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.6, no.8, pp.421-425_2, 1894-08-25 (Released:2010-10-13)

著者

榎本 祐嗣

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.433-439, 1999-08-25 (Released:2009-11-12)

参考文献数

22

---

One of the intriguing events accompanying large tsunamis, especially those that strike the Pacific coasts of Japan, is the luminous phenomenon; many historical Japanese documents have described how fire balls or pillars of fire seemed to come out from the sea when tsunami approached. Among 17 events of large tsunamis from 684 to 1946, where the surface wave magnitude was greater than 8 or the tsunami magnitude was greater than 3, nine tsunami events accompanied luminous phenomena. In spite the event's high probability, few explanations have been offered as to the source mechanism except luminescent planktonic organisms, which is hardly plausible because luminous tsunamis have been eye-witnessed even in the winter season when such planktonic organisms are less active, and even in the daytime when the intensity of light emitted from planktonic organisms is unlikely to exceed the day-time brightness.Most tsunami earthquakes are thought to be associated with sediments in the accretionary prism. One recent important finding is that large volumes of stable methane hydrate are present within ocean-floor sediments at water depths exceeding about 500m at lower temperatures. When the equilibrium conditions of coupled low temperature and moderate hydrostatic pressure are disturbed by an earthquake, the hydrate abruptly decomposes. Conversely, a breakdown of hydrate may cause a further mass movement, and a cascading chain of events may occur. Some eye-witness reports in historical documents strongly suggest that luminous phenomena associated with tsunami are attributable to methane hydrate disruption, not others causes such as luminescent planktonic organisms.

著者

松井 圭介

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.4, pp.451-471, 2014-08-25 (Released:2014-09-01)

参考文献数

51

被引用文献数

3 4

---

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. The five key findings of this study are: 1. A city design modeled on Heiankyou (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 chinju-sha 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 shingo (literally, a Shinto deity) title, “Tosho Daigongen,” and was enshrined angled towards the North Star (i.e. Nikko) 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. 2. Temples and shrines were under the control of the Tokugawa shogunate during the Edo Period, and the Honmatsu-seido (government-enforced main-branch temple system) was established through the enactment of jiinhatto (laws for temples). In addition, members of the public were forcibly linked to temples and shrines through their status as danka (temple supporters) under the Terauke seido (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. 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. 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 monzen-machi (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.(View PDF for the rest of the abstract.)

著者

武者 忠彦

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.125, no.4, pp.545-566, 2016-08-25 (Released:2016-09-12)

参考文献数

25

被引用文献数

2 3

---

In post-war Japan, many cityscapes have changed significantly with the development of high-speed transportation networks. Focusing on the process by which the normative way the city's future and its realization is imagined―that is, how the paradigm of city planning is accepted by the entities involved―the dynamics of how urban spaces resulting from this social processare reflected in space is investigated. The target area of this study, around JR Sakudaira Station, started campaigning for a bullet train in the 1970s. However, a centralist paradigm took hold due to developmental politics in the economic sector and the model of a modern city in the technological sector, and planning was relegated to the central government leadership. On the other hand, changes in the industrial structure and an aging farming population strengthened the development paradigm to promote a shift toward urban land use. The agricultural cooperative representing the interests of farmers in land use promoted land readjustment projects around Sakudaira Station. This project initially progressed through a government-led, design-centric approach. However, due to a lack of concrete planning ideas to counteract market principles, there was a push to change to a liberal paradigm that emphasizes the free market. Thus, the region's leading commercial cluster was formed with the focus on large-scale stores, contrary to the original plan.

著者

高田 亮

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.110, no.2, pp.245-256, 2001-04-25 (Released:2009-11-12)

参考文献数

39

被引用文献数

3 2

---

Basaltic volcanoes above oceanic crust or island-arc crusts develop calderas. Upon the formation of this caldera, the collapsed volume was generally far larger than erupted volume. Caldera width, its depth, and caldera horizontal width (CR) / volcano size (VR) depend on the physical properties of an oceanic crust. The CR/VR ratio decreases away from the ridge. At Fernandina volcano, Galapagos, the elongated caldera of 3.5 km × 2.5 km was formed in 1968 during a phase dominated by circumferential fissure eruptions after a phase dominated by radial fissure eruptions. At Kilauea volcano, Hawaii, during a phase dominated by central eruptions, several drain backs of lava lake ccurred from 1800, and, finally, a caldera of 1 km in diameter collapsed in 1924. Caldera collapse seems to be inevitable because accumulated crystals and solidified magma under a volcano increases gravitational instability. According to the gravitational collapse model proposed in this paper, it is difficult to determine when, how wide, and how deep a caldera collapse will occur. The magma plumbing system expands horizontally and vertically during long-term growth. Caldera collapse should contribute to vertical growth. Horizontal growth and vertical growth are governed by physical properties of the crust beneath the volcano; the former process is dominant in Hawaii, and the latter in Galapagos. In the case of Miyakejima volcano, the caldera collapse may be triggered by dike intrusions into a region with a low probability of intrusions or by an increase in the magma supply beneath the magma chamber. At the Miyakejima eruption in 2000, the caldera of 1.5 km in diameter formed in the shallow crust; ductile mass or dense magma with crystal mush may have moved downward or northwestward in the deep crust.

著者

三上 岳彦

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.114, no.1, pp.91-96, 2005-02-25 (Released:2009-11-12)

参考文献数

7

被引用文献数

1 1

著者

長久保 定雄

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.118, no.5, pp.758-775, 2009-10-25 (Released:2010-03-19)

参考文献数

112

被引用文献数

18 16

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Depending on imports for 98.6% for oil and natural gas requirements, it has been a long-cherished dream for Japan to have domestic hydrocarbon energy resources. Methane hydrate, an ice-like white solid composed of water and methane gas, is believed to be widely distributed in the sea area off Japan. Therefore, Japan's Methane Hydrate R & D Program was established by the Ministry of Economy, Trade and Industry in FY2001. The organization established to execute this program is the Research Consortium for Methane Hydrate Resources in Japan (MH21). This program is divided into three phases, extending over 18 years. Phase 1 ended in FY2008. The main results of Phase 1 are as follows: (1) World's first successful continuous production of methane gas from methane hydrate-bearing layers in onshore production tests, (2) For the first time in the world, methane hydrate concentrated zones, which have development potential, were identified in the eastern Nankai Trough area, (3) Experimental in-situ testing methods of artificial and natural core samples of methane hydrate-bearing sediments were established, (4) Probabilistic resource assessment method based on well and seismic data was established, and the amount of methane gas trapped in the eastern Nankai Trough area was estimated, (5) Japan's own simulator dedicated to evaluating the production behavior of methane gas from methane hydrate-bearing layers was developed. Besides the above-mentioned achievements, fundamental studies were conducted on the Environmental Impact Assessment and Methane Hydrate System. The following technological issues have been identified by a sensitivity analysis of the Economic Evaluation: (1) increasing gas production rate (2) improving recovery factor, (3) reducing rate of sand-induced problems, and (4) reducing cost of subsea system. Phase 2 began in April 2009 to resolve these issues. The most important issue in Phase 2 is to conduct two offshore production tests in the sea off Japan. This paper introduces detailed results of Phase 1 and issues to be tackled during and after Phase 2.

著者

大島 章一

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.109, no.3, pp.474-482, 2000-06-25 (Released:2010-10-13)

参考文献数

25