著者

西川 一雄 西堀 剛 小早川 隆 但馬 達雄 上嶋 正人 三村 弘二 片田 正人

出版者

Japan Association of Mineralogical Sciences

雑誌

岩石鉱物鉱床学会誌 (ISSN:00214825)

巻号頁・発行日

vol.78, no.2, pp.51-64, 1983-02-05 (Released:2008-08-07)

参考文献数

24

被引用文献数

3 4

---

The late Cretaceous Koto Rhyolite is divided into two groups according to the succession. Each group forms an igneous cycle. The older group consists of the Kaiwara Welded Tuff and the Hatasho Quartz Porphyry, and their relationship is transitional in the field showing their co-magmatic origin. The Kaiwara Welded Tuff erupted apparently first as vesiculated magma from the top of the magma_??_reservoir followed by the intrusive phase of the Hatasho Quartz Porphyry. There are enrichment of phenocrysts such as quartz and alkali feldspar in the Kaiwara Welded Tuff, whereas plagioclase phenocrysts are more commo in the Hatasho Quartz Porphyry. The K/Rb ratios of the whole rocks are larger in the Hatasho Quartz Porphyry than in the Kaiwara Welded Tuff. The younger group consisting of the Yatsuoyama Pyroclastic Rock and the Inugami Granite Porphyry is also considered to be of co-magmatic origin although obvious intimate relationship of the two units could not be observed in the field. The differences between them in the composition of phenocryst minerals and K/Rb ratio of the whole rocks are similar to and somewhat larger than those between the Kaiwara Welded Tuff and the Hatasho Quartz Porphyry. The Inugami Granite Porphyry of the last igneous activity intruded along the ring faults whose center subsided stepwise and resulted in a double ring dike about 30km across. Thus the Koto Cauldron was composed. Natural remanent magnetism through the Koto Rhyolite suggests a clock-wise movement of the area during its igneous activity.

著者

早川 文敏

出版者

京都大学フランス語学フランス文学研究会

雑誌

仏文研究 (ISSN:03851869)

巻号頁・発行日

vol.35, pp.105-136, 2004-09-15

著者

早川 知道 伊美 裕麻 伊藤 孝行

出版者

公益社団法人 日本経営工学会

雑誌

日本経営工学会論文誌 (ISSN:13422618)

巻号頁・発行日

vol.66, no.4, pp.317-326, 2016

---

日本のOpenStreetMap(OSM) は活発な活動により多くの成果物が作成されているが, 持続可能なコミュニティとなり多くの社会活動に成果物を活用するためには, 様々な課題がある. 本稿では, 日本のOSMの現状分析を行い, 今後の課題を明確にし, 日本のコミュニティに問題提起するための検証をした. 最初に, 成果物数と貢献者数について日本とOSM先進地域で比較調査分析し, 日本のOSMの現状と課題を明確にした. 次に, OSMの品質の要素である, 成果物の粒度について調査した. 調査の結果, 貢献者をいかに定着させるか, さらには, 新たな貢献者をいかに増やすのか, が日本のOSMコミュニティの課題となった.

著者

早川 由紀夫 井村 隆介

出版者

特定非営利活動法人日本火山学会

雑誌

火山 (ISSN:04534360)

巻号頁・発行日

vol.36, no.1, pp.p25-35, 1991-04

被引用文献数

4

---

The eruptive history of Aso volcano for the past 80,000 years is revealed by tephrochronology and loess-chronometry. Around the Aso caldera is a thick accumulation of loess, which is intercalated with numerous Aso tephra layers of limited dispersal as well as three widespread tephra layers of known age that are good marker horizons ; the Akahoya ash (6.3 ka), the Aira-Tn ash (22 ka), and the Aso-4 ignimbrite (70 ka). Loess-chronometry is based on the assumption that, in the Aso region, the accumulation rate of loess has been constant as 12 cm/ky from 80 ka to the present. Most of tephra layers after the caldera-forming Aso-4 eruption are composed of volcanic sand or scoria lapilli of basaltic andesite composition. However the 27 ka Kusasenri dacite (SiO_2 = 67%) pumice is a conspicuous exception. The large volume of 5.85 km^3 (bulk) and wide dispersal of this pumice suggests that it is a product of plinian eruption. From October 5 to the end of November 1989, the Nakadake crater of Aso volcano was in eruption. Ash was uninterruptedly emitted from a 500-1,000 m high eruption column coming out of the crater. The average discharge rate of ash was 5 × 10^7 kg/day. The total mass of ash discharged during the two months reached 3 × 10^9 kg. The penultimate eruption in recent history was June-August 1979, when 7.5 × 10^9 kg of ash was discharged. Outside the Aso caldera, the thickness of the 1989 ash is less than 1 cm. It is almost impossible to detect an old ash layer of thickness about 1 cm in a loess cross section, suggesting that sedimentary records 10 km away from a volcano are insufficient to reconstruct past eruptions smaller than 10^<10> kg. Eruptions smaller than 10^<10> kg can be determined only from proximal deposits. The history of eruptions of Aso volcano over the last few thousand years is tentatively determined from cross sections 2-4 km west of the Nakadake crater. After a 580-1,250 year dormant period, Aso volcano became active about 1,780 years ago. From then, small eruptions each with 10^9-10^<10> kg ash discharge have been repeated 48-88 times up to the present. The duration of each eruption was a few months, and the dormant interval between eruptions averaged 20-37 years.

著者

早川 由紀夫

出版者

特定非営利活動法人日本火山学会

雑誌

火山. 第2集 (ISSN:04534360)

巻号頁・発行日

vol.29, no.2, 1984-07-01

著者

早川 由紀夫

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.107, no.3, pp.Plate1-Plate2, 1998-06-25 (Released:2009-11-12)

著者

早川 由紀夫

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.115, no.2, pp.Plate3-Plate4, 2006-04-25 (Released:2009-11-12)

著者

早川 由紀夫

出版者

特定非営利活動法人日本火山学会

雑誌

火山. 第2集 (ISSN:04534360)

巻号頁・発行日

vol.25, no.4, pp.305-306, 1980-12-01

著者

荒牧 重雄 柵山 雅則 早川 由紀夫 中村 保夫 巽 好幸

出版者

特定非営利活動法人日本火山学会

雑誌

火山. 第2集 (ISSN:04534360)

巻号頁・発行日

vol.26, no.2, 1981-07-01

著者

白尾 元理 早川 由紀夫

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.104, no.4, pp.Plate1-Plate2, 1995-08-25 (Released:2009-11-12)

著者

早川 由紀夫

出版者

特定非営利活動法人日本火山学会

雑誌

火山. 第2集 (ISSN:04534360)

巻号頁・発行日

vol.27, no.2, pp.174-175, 1982-07-01

著者

早川 由紀夫

出版者

特定非営利活動法人日本火山学会

雑誌

火山. 第2集 (ISSN:04534360)

巻号頁・発行日

vol.31, no.4, pp.287-288, 1986-12-26

著者

早川 裕弌 松多 信尚 前門 晃 松倉 公憲

出版者

日本地形学連合

雑誌

地形 (ISSN:03891755)

巻号頁・発行日

vol.34, no.1, pp.21-36, 2013-01-25

---

Recession rates of four waterfalls formed by the surface deformation of the Chelungpu Fault at the time of Chi-Chi Earthquake on September 21, 1999 in central Taiwan were measured in the field and assessed with an empirical model of waterfall erosion. The model represents the balance between the erosive force of streams versus bedrock resistance with relevant environmental parameters of discharge (drainage area and precipitation), waterfall form and bedrock strength. The recession rates of three waterfalls increased from the first 6 years to the following 4 years. This increase in the recession rates basically corresponds to the changes in environmental factors including precipitation increase and waterfall width narrowing. The recession rate of another waterfall decreased, but this can be explained by artificial modification of riverbed. The recession rates are very high comparing with waterfalls in other places, probably due to large amount of hard gravels transported on the weak bedrock from the upstream areas.

著者

早川 典子

出版者

公益社団法人 高分子学会

雑誌

高分子 (ISSN:04541138)

巻号頁・発行日

vol.54, no.4, pp.240-241, 2005-04-01 (Released:2011-10-14)

参考文献数

3

著者

酒井 英男 小林 剛 岡田 敏美 芳野 赳夫 早川 正士 富沢 一郎 中山 武 太田 健次

出版者

独立行政法人防災科学技術研究所

雑誌

防災科学技術研究所研究資料 (ISSN:0917057X)

巻号頁・発行日

vol.157, pp.287-317, 1993-03-29

---

Electromagnetic properties were measured at the joint observation of the explosion seismic experiment at Ooyama, Toyama Prefecture on Oct. 17, 1991. The explosion was induced by 450 kg gun powder placed at a depth of 75 m. This paper represents the preliminary results of the experiments. (1) Electric self-potential : The measurement of the electric self-potential (S.P.) was made at two stations. One station was set up around the explosion point, and the other station about 1.5 km apart from the explosion point. At the station about 1.5 km apart from the explosion area, we observed no distinct change in S.P. before the arrival of seismic wave. At the station around the explosion point, four electrodes were arranged in the line of east-west direction crossing the explosion point. The distance of the each electrode from the explosion point ranges from 10 m to 100 m. The seismograph sensor was arranged at the distance of 130 m for the comparion with the change of the S.P. Up to 150 mV changes in S.P. were observed by the electrode couples before the arrival of seismic wave. The detailed analsis revealed that the induced changes in the S.P. consist of two portions : the fluctuation with shorter period (〜0.001 second) and with the frequency of the longer period (〜0.05 second). The propagation speed of the fluctuation with the shorter period was much higher than that of the fluctuation with the longer period. The fluctuation of the shorter period might have been related to the explosion process of gun powder. About the fluctuation with the frequency of the longer period, the following properties were elucidated. The amplitude of the fluctuation in S.P. is in proportion to the span length of the electrode couples. The fluctuation in S.P. arrived faster at the electrode couples situated nearer to the explosion point. (2) Magnetic field The magnetic field was measured by the fluxgate magnetometer at the site 35m north from the explosion point. The apparentchanges of magnetic vertical component and of horizontal component were observed at the time of 0.25 seconds after the explosion. Increase of total magnetic field of 2〜3nT after the explosion was found. This increment was confirmed by the total magnetic field survey around the fluxgate sensor. (3) VLF electromagnetic radiation No clear radiation of VLF electromagnetic wave was seen because of the possible contamination of the other natural radio noises. However, a possibility of VLF radiation connot be denied. Further study of the VLF data should be carried out.

著者

角田 信三 早川 善平 松場 喜六

出版者

財団法人 日本消化器病学会

雑誌

消化器病学 (ISSN:21851158)

巻号頁・発行日

vol.2, no.2, pp.325-329, 1937-03-10 (Released:2011-06-17)

著者

早川 ひろみ

出版者

宮城県特別支援教育センター

雑誌

特別支援教育長期研修員報告書

巻号頁・発行日

vol.2009, pp.中扉1枚,73-82, 2009

著者

堀 素夫 早川 宗八郎 鞆津 武 牧島 象二

出版者

社団法人 日本化学会

雑誌

工業化学雑誌 (ISSN:00232734)

巻号頁・発行日

vol.61, no.6, pp.638-641, 1958

---

本研究はセメント焼塊のような不定形の焼結物の焼結度を迅速かつ連続的に推定する目的で,これらの焼結粒子充填試料についてγ 線吸収ならびに超音波吸収の測定を行い, 従来の方法によるカサ密度, 見掛け密度, 気孔率ないし固結強度等の測定結果を比較検討したものである。まずγ 線吸収については,充填粒子の形状,粒度,密度等のいかんにかかわらず,同一組成の試料のγ 線吸収係数とカサ密度との間にはほぼ完全な比例関係が成立するので,γ 線吸収実験結果からただちにそのカサ密度を推定することができる。ただし充填試料自体の見掛け密度を推定するためには,充填粒子間の空隙部分を適当な媒質でおきかえる必要があり,置換媒液の浸透性等に問題が残る。次に超音波吸収の場合には,測定結果が試料の粒度によって著しく変動するため, γ 線吸収の場合のように簡単な関係はえられないが, 一般的な傾向として吸収係数は焼結度の増加とともに減少するといえる。

著者

早川 聞多

出版者

国際日本文化研究センター

雑誌

日本研究 : 国際日本文化研究センター紀要

巻号頁・発行日

vol.16, pp.125-159, 1997-09-30

---

本稿は鈴木春信作『今様妻鑑』の絵解きを通して、春信の見立絵の特色を論じようとするものである。『今様妻鑑』は上中下三冊からなる艶本で、各巻は春信作の春画十一図と作者未詳の艶笑小話二話から成る。本稿で取り上げるのは主に春画であるが、各図は平安時代に成つた『和漢朗詠集』の漢詩句を頭書し、それを基に春信独特の見立てを春画によつて試みたものである。その絵解きを通して、「外面の極端な相違と内面の意外な共鳴」といふ春信独特の見立絵の構造を明らかにする。

著者

早川 勇

出版者

愛知大学語学教育研究室

雑誌

言語と文化 (ISSN:13451642)

巻号頁・発行日

no.14, pp.1-20, 2006-01