著者

吉田 明夫 青木 元

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.111, no.2, pp.212-221, 2002-04-25 (Released:2009-11-12)

参考文献数

26

被引用文献数

2

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We show that conspicuous seismic quiescence occurred in large areas along the coast of the Japan Sea before the 1891 Nobi, 1964 Niigata, 1983 Central Japan Sea, and 2000 Western Tottori Prefecture Earthquake. If we had noticed the quiescence that had appeared since the late 1980s along the northern coasts of Shimane, Tottori, and Hyogo Prefectures and had remembered the feature that a large earthquake in the coastal region of the Japan Sea is likely to be preceded by a widely extended seismic quiescence along the coast, we could have paid close attention to the focal region of the Western Tottori Prefecture Earthquake. We think the occurrence of seismic quiescence in a large area before a large earthquake implies that the preparatory process proceeds not only in the focal region, but in the circumferential areas as well.

著者

岩崎 暁生 青木 元彦 妹尾 吉晃

出版者

北日本病害虫研究会

雑誌

北日本病害虫研究会報 (ISSN:0368623X)

巻号頁・発行日

vol.2011, no.62, pp.194-198, 2011-12-27 (Released:2017-12-20)

参考文献数

10

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In the summer and autumn of 2010, a mass outbreak of the beet webworm Spoladea recurvalis in sugar beet occurred throughout the entire sugar beet cultivation area of Hokkaido, the northern island of Japan. Serious damage was incurred in mid-August in the southern area, in mid to late August in the central area and the Tokachi district of the eastern area, and after mid-September in the Okhotsk district of the eastern area. Through field research in the central area, the migration period of adult moths was estimated to be mid-July. The early and/or mass migration of moths in addition to the higher summer temperature suitable for the development of the pest from their immature stages might accelerate the unusual mass occurrence of the pest throughout the year. Several insecticides mainly belonging to organophosphates and synthetic pyrethroids were found to be less effective on middle-to-late instar larvae in both insect dipping and diet dipping experiments. Insect growth regulators, on the other hand, were found to be effective for the control of larvae of the pest on sugar beet fields even under such mass occurrence.

著者

中村 雅基 金沢 敏彦 佐藤 利典 塩原 肇 島村 英紀 仲西 理子 吉田 康宏 趙 大鵬 吉川 一光 高山 博之 青木 元 黒木 英州 山崎 貴之 笠原 順三

出版者

気象庁気象研究所

雑誌

気象研究所研究報告 (ISSN:0031126X)

巻号頁・発行日

vol.53, no.1, pp.1-28, 2002

被引用文献数

5

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中部日本におけるP波およびS波の3次元速度構造を地震波走時トモグラフィーを用いて求めた。その際、定常観測点で得られる自然地震を対象とした観測値だけでなく、人工地震や海域における臨時観測点等を用いた観測値を積極的に利用した。得られた成果は以下の通りである。沈み込むフィリピン海プレートと思われる高速度域が検出された。フィリピン海プレートは、少し高角度で沈み込み始め、その後なだらかになり、最後は高角に沈み込んでいる。35°N、136.5°E付近では、フィリピン海プレートが分かれている。将来発生が懸念されている東海地震の固着域の北西隣は、プレート間カップリングが弱い。35.6°Nから35.8°N、137.5°E、深さ100kmから200km付近で、非地震性のフィリピン海プレートが検出された。

著者

吉田 明夫 青木 元

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.111, no.2, pp.212-221, 2002-04-25

参考文献数

26

被引用文献数

1 2

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We show that conspicuous seismic quiescence occurred in large areas along the coast of the Japan Sea before the 1891 Nobi, 1964 Niigata, 1983 Central Japan Sea, and 2000 Western Tottori Prefecture Earthquake. If we had noticed the quiescence that had appeared since the late 1980s along the northern coasts of Shimane, Tottori, and Hyogo Prefectures and had remembered the feature that a large earthquake in the coastal region of the Japan Sea is likely to be preceded by a widely extended seismic quiescence along the coast, we could have paid close attention to the focal region of the Western Tottori Prefecture Earthquake. We think the occurrence of seismic quiescence in a large area before a large earthquake implies that the preparatory process proceeds not only in the focal region, but in the circumferential areas as well.

著者

海野 徳仁 河野 俊夫 岡田 知己 中島 淳一 松澤 暢 内田 直希 長谷川 昭 田村 良明 青木 元

出版者

公益社団法人 日本地震学会

雑誌

地震 第2輯 (ISSN:00371114)

巻号頁・発行日

vol.59, no.4, pp.325-337, 2007-03-25 (Released:2013-08-05)

参考文献数

21

被引用文献数

1 5

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Hypocenters of the main shocks and aftershocks of the 1933 Mjma 7.1, 1936 Mjma 7.4, 1937 Mjma 7.1, 1939 Mjma 6.9, 1978 Mjma 7.4, and 1981 Mjma 7.0 Miyagi-oki, NE Japan, earthquakes are relocated by using S-P times reported in the Seismological Bulletin of the Japan Meteorological Agency (JMA) and those re-read from original smoked-paper seismograms observed at Mizusawa station of National Astronomical Observatory of Japan (NAOJ) and at Mukaiyama station of Tohoku University. In order to avoid large errors caused by inaccuracies in the arrival times of P- and S-waves and the limited number of observation stations, we determined hypocenters by using a grid search method based on the assumption that these events occurred at the boundary between the subducting Pacific plate and the overriding plate. The main shock epicenters of the 1933, 1936, 1937, and 1978 earthquakes are determined close to each other, and distributions of their aftershocks show that aftershock areas of 1933, 1936, and 1937 events partly overlap with that of the 1978 event and occupy its easternmost, central, and westernmost portions, respectively. It is likely that the 1933, 1936, and 1937 events possibly ruptured a part of the source area of the 1978 event, that is the eastern, central, and western portions, respectively. Locations of the main shock and aftershock area of the 1939 event are adjacent to the eastern edge of the source area of 1978 event. After the 1978 event, the 1981 earthquake had occurred there following the slip on the asperities in the presumed Miyagi-oki earthquake source area.

著者

青木 元也 直井 保 竹本 博安 遠藤 久芳 橋爪 豊 安藤 文隆

出版者

独立行政法人 海上技術安全研究所

雑誌

船舶技術研究所研究発表会講演集 (ISSN:02857332)

巻号頁・発行日

no.23, pp.59-63, 1974-05-15

著者

青木 元也 遠藤 久芳

出版者

独立行政法人 海上技術安全研究所

雑誌

船舶技術研究所研究発表会講演集 (ISSN:02857332)

巻号頁・発行日

no.23, pp.64-67, 1974-05-15