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著者 浅田 伸彦|
発行日 2002-09
出版物タイトル 岡山実験動物研究会報
19巻
資料タイプ 学術雑誌論文
著者 高橋 純夫| 本多 淳一| 真鍋 芳江| 松村 龍成| 竹内 栄|
発行日 2003-09
出版物タイトル 岡山実験動物研究会報
20巻
資料タイプ 学術雑誌論文
著者 高橋 純夫| 松村 龍成| 竹内 栄|
発行日 2004-09
出版物タイトル 岡山実験動物研究会報
21巻
資料タイプ 学術雑誌論文
著者 Department of Earth Sciences, Faculty of Science, Okayama University|
発行日 2009-12-25
出版物タイトル Okayama University Earth Science Report
16巻
1号
資料タイプ その他
JaLCDOI 10.18926/ESR/19850
タイトル(別表記) 岡山県に分布する白亜紀前期羽山層砕屑物質の供給源:砕屑粒の鉱物化学組成とモード組成から導かれる制約
フルテキストURL 016_029_042.pdf
著者 アシード ダニエル| 鈴木 茂之| 柴田 次夫|
抄録 Petrographic and phase chemistry studies of detrital grains were carried out on sandstones from the Lower Cretaceous Hayama Formation, Inner Zone of Southwest Japan, to determine their provenance and the tectonic setting during the early Cretaceous. The results of the modal mineralogy suggest that the Hayama Formation has magmatic arc provenance and that deposition of the sediments took place in the back-arc areas with detritus mostly derived from the magmatic arc and rifted continental margins. The chemical compositions of chromian spinel, chlorite and sphene indicate that significant proportions of the detrital grains were derived from mafic and/or ultramafic sources. The source areas are the mafic and ophiolitic rocks in the Sangun-Renge and Akiyoshi terranes and the felsic volcanic rocks probably from either the Akiyoshi terrane or a source not presently exposed in southwest Japan. However, minor amounts of the detritus were derived from the basement rocks; i.e., carbonates and siliciclastic rocks of the Akiyoshi terrane and the metamorphosed mafic rocks of the Chizu terrane.
キーワード modal analysis sandstone mineral chemistry provenance Hayama Formation
出版物タイトル Okayama University Earth Science Report
発行日 2009-12-25
16巻
1号
開始ページ 29
終了ページ 42
ISSN 1340-7414
言語 英語
著作権者 岡山大学地球科学研究報告編集委員会
論文のバージョン publisher
NAID 120002309000
JaLCDOI 10.18926/ESR/19849
タイトル(別表記) ガーナ,アシャンティ火山帯南部に分布する古原生代変火山岩類のSr-Nd 同位体組成
フルテキストURL 016_009_028.pdf
著者 ダムパリ サムエル| 柴田 次夫| アシード ダニエル| 岡野 修| マーヌ ジョンソン| サチ パトリック|
抄録 Neodymium (Nd) and strontium (Sr) isotopic data are presented for Paleoproterozoic metavolcanic rocks in the southern part of the Ashanti volcanic belt of Ghana. The metavolcanic rocks are predominantly basalts/basaltic andesites and andesites with minor dacites. Two types of basalts/basaltic andesites (B/A), Type I and Type II, have been identified. The Type I B/A are stratigraphically overlain by the Type II B/A, followed by the andesites and the dacites. The analyzed volcanic rocks commonly have low initial (87)Sr/(86)Sr ratios consistent with previous studies on Paleoproterozoic rocks from the West African craton. The LREE-depleted, tholeiitic Type I B/A exhibit back-arc basin geochemical signatures and show high positive epsilon Nd (i.e., ε(Nd) (2.1 Ga) = +3.89 to +7.21), which suggest a long term depleted source and also indicate that they were produced in an entirely oceanic environment devoid of influence of continental crust. The isotope signatures are thus consistent with the previously published trace element data of the Type I basalts/basaltic andesites in suggesting that their parent magma was generated from a depleted mantle. The Type I B/A have Nd model ages (T(DM2)) of 1.83–2.09 Ga similar to their formation ages, suggesting that they were juvenile at their time of formation. The andesites and the Type II B/A andesites show LREE-enriched patterns and exhibit characteristics of subduction zone-related magmas, and show initial ε(Nd) (2.1Ga) values of –1.15 to + 1.35 and Nd model ages (T(DM2)) of 2.32–2.58 Ga. The LREE-enriched dacitic porphyry also exhibits characteristics of subduction zone-related magmas, and have initial ε(Nd) (2.1Ga) value of –2.24 and Nd model ages (T(DM2)) of 2.64 Ga. The Nd isotopic data confirms the juvenile character of the Birimian crust, but also suggests some contributions of a pre-Birimian crustal material (or Archean?) in the genesis of some of the metavolcanic rocks. Our isotopic result is consistent with the island arc complex model which views Paleoproteozoic terranes of West Africa in the context of subduction–accretion processes.
キーワード Sr–Nd isotopes petrogenesis tectonic setting Birimian metavolcanics Ashanti volcanic belt
出版物タイトル Okayama University Earth Science Report
発行日 2009-12-25
16巻
1号
開始ページ 9
終了ページ 28
ISSN 1340-7414
言語 英語
著作権者 岡山大学地球科学研究報告編集委員会
論文のバージョン publisher
NAID 120002308985
JaLCDOI 10.18926/ESR/19848
タイトル(別表記) The first Japanese word "chishitsu-gaku" for the "geology" was proposed by Genpo Mitsukuri (1799-1863)
フルテキストURL 016_001_007.pdf
著者 岡田 博有| 鈴木 茂之|
抄録 The first Japanese word "chishitsu-gaku" for the "geology" was proposed by Genpo Mitsukuri, a scientific contributor in the Tokugawa regime in the 19th century, who was born in 1799 in Tsuyama in Western Honshu, Japan and had worked for scientific activities of the Tokugawa government from 1839 to 1863. His major works for the first making of the "chishitsu-gaku" for the "geology" have been presented in this paper, also showing his contribution to Japanese sciences.
キーワード Genpo Mitsukuri "chishitsu-gaku" 19th century
出版物タイトル Okayama University Earth Science Report
発行日 2009-12-25
16巻
1号
開始ページ 1
終了ページ 7
ISSN 1340-7414
言語 日本語
著作権者 岡山大学地球科学研究報告編集委員会
論文のバージョン publisher
NAID 120002309076
著者 Department of Earth Sciences, Faculty of Science, Okayama University|
発行日 2009-12-25
出版物タイトル Okayama University Earth Science Report
16巻
1号
資料タイプ その他
著者 Department of Earth Sciences, Faculty of Science, Okayama University|
発行日 2009-12-25
出版物タイトル Okayama University Earth Science Report
16巻
1号
資料タイプ その他
JaLCDOI 10.18926/ESR/15034
タイトル(別表記) 中国寧夏地域における日照時間から日積算日射量の推定
フルテキストURL 015_079_086.pdf
著者 楊 勤| 塚本 修|
抄録 For the estimation of daily solar radiation from sunshine duration, observation data of Yinchuan station in Ningxia, China was used. Using a linear relationship between solar radiation and extraterrestrial radiation including relative sunshine duration and daylength, we obtained local coefficients s a =0.18, s b =0.62 from past five years data(1981-1985). Using the same method, coefficients for Guyuan region were confirmed too as a representative of south part of Ningxia province. Applying the local coefficients and calculation formula of solar radiation, we validated daily solar radiation of two years(1986-1987) of Yinchuan station and four years(1991-1994) of Guyuan station. The results showed high correlation coefficients of R2=0.94 in Yinchuan and R2=0.85 in Guyuan. Error analysis was applied using mean bias error(MBE), mean absolute bias error(MABE), root mean square error(RMSE),mean absolute percentage error(MAPE) on solar radiation of Yinchuan(1973-2006) and Guyuan(1986-2006) stations. Results showed that mean absolute bias error(MABE) was less than 13% and 17% in Yinchuan station and Guyuan station respectively. Then we have applied this method to the estimation of daily solar radiation at ‘Yongning’ station(near Yinchan) with the sunshine duration data at ‘Yongning’. The estimated values were compared with observed daily solar radiation at Yinchuan as past twelve years data(1989-2000). The results showed good linear relationship with high correlation coefficient of R2= 0.88.
キーワード Daily solar radiation Extraterrestrial radiation Relative sunshine duration Local coefficient
出版物タイトル Okayama University Earth Science Report
発行日 2009-03-31
15巻
1号
開始ページ 79
終了ページ 86
ISSN 1340-7414
言語 英語
著作権者 岡山大学地球科学研究報告編集委員会
論文のバージョン publisher
NAID 120002307142
JaLCDOI 10.18926/ESR/15033
タイトル(別表記) Climatological study on large-scale situation associated with the cool summer around the Northeastern Japan in 1990s (in comparison with that in 1970s)
フルテキストURL 015_067_077.pdf
著者 妹尾 ゆかり| 加藤 内藏進|
抄録 It is pointed out by the previous studies that the Baiu front tends to stagnate around the Japan Islands even in midsummer season in 1990s, although the global warming is going on. The present study examined the climatological features of the appearance of daily fronts on the surface weather maps and the large-scale factors associated with the activity of the polar frontal zone to the north of the Baiu frontal zone based on the observational data in the summer of 1971-2000. It was found that the midsummer when the Baiu front tends to stagnate around the Japan Islands appeared rather frequently in 1970s as in 1990s. However, the baroclinicity around the Eurasian polar frontal zone was stronger in 1970s than in 1990s. Thus while the fronts around the Japan Islands in midsummer were greatly due to the southward invasion of cold front associated with the disturbances on the polar frontal zone in 1970s, the Okhotsk High tends to stagnates to the northeast of the fronts around the Japan Islands in 1990s.
キーワード Abnormal weather in summer Climate system in East Asia Cool summer Climate variation
出版物タイトル Okayama University Earth Science Report
発行日 2009-03-31
15巻
1号
開始ページ 67
終了ページ 77
ISSN 1340-7414
言語 日本語
著作権者 岡山大学地球科学研究報告編集委員会
論文のバージョン publisher
NAID 120002307910
JaLCDOI 10.18926/ESR/15025
タイトル(別表記) Morphology and Anatomy of Holocene Raised Coral Reef Terraces in Kodakara Island, Tokara Islands, northwestern Pacific, Japan
フルテキストURL 015_033_065.pdf
著者 濱中 望| 菅 浩伸| 中島 洋典| 堀 信行| 岡本 健裕| 大橋 倫也| 安達 寛|
抄録 Well-developed Holocene raised coral reef terraces are formed in Kodakara Island (29°13'N 129°19'E), Tokara Islands, northwestern Pacific, Japan. Detailed morphology and sedimentary structure of the raised reef terraces are observed by field survey through the terraces surface and core drillings. The Holocene raised reef in Kodakara Island are divided into three terraces (TI to III). The surface geo-biological facies and paleo-morphology such as spur and groove system or reef mounds are well preserved on these terraces. The raised coral reefs in Kodakara Island consist of reef flats and reef slopes. No lagoon formed in these terraces. On the raised reef surface, we observed five distinct reefal facies (S-f1-5). The platy and encrusting Acropora facies is the major constituent of the terrace surfaces. We obtained seven drilling cores (B1 to 7) from Terraces I and II along a transect in the southern part of the island. The thickness of the Holocene reef is more than 14m which is approximately equivalent to the Holocene reefs in the middle and southern Ryukyu Islands. Sedimentary structure consists of seven facies (C-f1-7: five reefal and two non-reefal facies). The drilling cores indicating the shallowing sequence at the upward of the cores which characterized by platy-encrusting Acropora facies overlying massive Porites, favid and/or encrusting-foliaceous coral facies. It may indicate the environmental change such as wave-energy gradients and turbidity during the reef development.
キーワード Holocene coral reef terrace drilling sedimentary structure Tokara Islands northwestern Pacific
出版物タイトル Okayama University Earth Science Report
発行日 2009-03-31
15巻
1号
開始ページ 33
終了ページ 65
ISSN 1340-7414
言語 日本語
著作権者 岡山大学地球科学研究報告編集委員会
論文のバージョン publisher
NAID 120002308005
JaLCDOI 10.18926/ESR/15024
タイトル(別表記) Microscopic observations of the recent soils: a step for understanding the paleosols
フルテキストURL 015_009_032.pdf
著者 福地 亮| 鈴木 茂之|
抄録 The microscopic observations of the recent soil horizons were conducted in Okayama, Japan (moderate climate). The several soil horizons, including two surface (epipedon) and three subsurface horizons, were recognized in the forest, poorly vegetated hill, and riverside around the Okayama University. The umbric epipedon can be segregated from the organic-rich subsurface horizons by the scattered organic materials in thin sections. The ochrich epipedon shows the sandy matrix without any cements and the illuviation of clay minerals. The subsurface horizons identified in the study area are as follows: albic, argillic, and cambic horizons. Each subsurface horizon shows the specific structures in thin sections. The albic horizon is characterized by the absence of the illuviation. The argillic horizon definitely shows the clayey matrix and the illuviation of clay minerals. The primary structures may be retained in the cambic horizon. The microscopic examination of the Miocene paleosols from the Ukan-cho, Okayama, was attempted. By comparing the recent soils, the cambic horizon and spodic horizon, which is characterized by the concentration of sesquioxides, are identified in the paleosols. This attempt suggests that the microscopic observations of the recent soils is a useful guide to understanding the paleosols
キーワード soil paleosol soil horizon soil structure microscopic observation
出版物タイトル Okayama University Earth Science Report
発行日 2009-03-31
15巻
1号
開始ページ 9
終了ページ 32
ISSN 1340-7414
言語 日本語
著作権者 岡山大学地球科学研究報告編集委員会
論文のバージョン publisher
NAID 120002307964
JaLCDOI 10.18926/ESR/15022
タイトル(別表記) Permian and Triassic molluscan fossils from the Maizuru Zone,Okayama City, Southwest Japan
フルテキストURL 015_001_008.pdf
著者 中澤 圭二| Roger Lyman Batten| 鈴木 茂之| 宇和田 英人|
抄録 Permian and Triassic molluscan fossils are found from Mitsu-area, Okayama City, Southwest Japan. Permian bivalve and gastropod fossils are collected from mudstones of the Upper Formation of the Maizuru Group. 4 species of bivalves (Nuculopsis? sp. ind., Leptodesma sp. ind., Streblopteria cf. eichwaldi, Posidonia sp. ind.) and 5 species of gastropods (Worthenia cf. corrugata, Callitomaria n. sp. cf. stanislavi, Apachella n. sp. ind., ??Eunemopsis like trochid, ??Yunnania sp.) are identified. Lower Triassic bivalve fossils are collected from sandstones of the Oono Formation. Neoschizodus cf. laevigatus and Bakevellia (Maizuria) kambei are identified.
キーワード Permian Triassic bivalve and gastropod fossils the Maizuru Zone Mitsu area
出版物タイトル Okayama University Earth Science Report
発行日 2009-03-31
15巻
1号
開始ページ 1
終了ページ 8
ISSN 1340-7414
言語 日本語
著作権者 岡山大学地球科学研究報告編集委員会
論文のバージョン publisher
NAID 120002307247
著者 樋口 慶郎| 井上 亜希子| 玉之内 啓満| 服部 隆康| 本水 昌二|
発行日 1999
出版物タイトル 分析化学
48巻
5号
資料タイプ 学術雑誌論文
著者 山本 幸市| 本水 昌二|
発行日 2001
出版物タイトル 分析化学
50巻
1号
資料タイプ 学術雑誌論文
著者 二宮 崇彦| 李 啓熒| 大島 光子| 本水 昌二|
発行日 2000
出版物タイトル 分析化学
49巻
7号
資料タイプ 学術雑誌論文
著者 二宮 崇彦| 大下 浩司| 大島 光子| 本水 昌二|
発行日 2004
出版物タイトル 分析化学
52巻
9号
資料タイプ 学術雑誌論文
著者 李 貞海| 大島 光子| 本水 昌二|
発行日 2004
出版物タイトル 分析化学
53巻
4号
資料タイプ 学術雑誌論文
著者 小西 明伸| 高柳 俊夫| 大島 光子| 本水 昌二|
発行日 2004
出版物タイトル 分析化学
53巻
1号
資料タイプ 学術雑誌論文