著者

鈴木 毅彦 村田 昌則 大石 雅之 山崎 晴雄 中山 俊雄 川島 眞一 川合 将文

出版者

日本第四紀学会

雑誌

第四紀研究 (ISSN:04182642)

巻号頁・発行日

vol.47, no.2, pp.103-199, 2008-04-01 (Released:2009-04-25)

参考文献数

36

被引用文献数

2 2

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立川断層の活動史を明らかにするため,4本のコアと狭山丘陵を調査した.狭山丘陵に産出するテフラSGOはMTB1・武蔵村山コア中のテフラに対比される可能性があり,同じくSYG(1.7 Ma)はMTB1・武蔵村山コア中のテフラに,箱根ヶ崎テフラ群(約2.0 Ma)は武蔵村山・MTB2コア中のテフラに対比された.また,Ebs-Fukuda(1.75 Ma)がMTB1コア中に,Kd44(1.968~1.781 Ma)が武蔵村山・瑞穂コア中に,Tmg-R4(2.0 Ma)がMTB2コア中に検出された.三ツ木地区においては,SYG層準が約126mの北東側隆起の変位を受けている.SYGと箱根ヶ崎テフラ群の変位量には累積はなく,立川断層は2.0~1.7 Maの間は活動していなかった.断層は南東・北西セグメントからなる.従来,地下でのみ認定された瑞穂断層は北西セグメント南東部であり,両セグメントは約1.5kmの区間を並走している.南東セグメント内では北西端部ほど累積変位量が小さいが,並走する北西セグメントの累積変位量を加味すれば,断層全体では南東セグメント北西端で累積変位量は急減しない.

著者

浅見 祐香 野村 和孝 嶋田 洋徳 大石 裕代 大石 雅之

出版者

公益社団法人 日本心理学会

雑誌

心理学研究 (ISSN:00215236)

巻号頁・発行日

pp.92.19053, (Released:2021-03-31)

参考文献数

30

被引用文献数

2

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The present study aimed to clarify the cognitive and behavioral features of the process from the onset of stealing to the development of kleptomania. We also analyzed the differences between kleptomania and shoplifting for personal gain. Semi-structured interviews were conducted with 25 participants (15 patients with kleptomania, 4 shoplifters, and 6 with other addictions). An analysis based on a modified grounded theory approach (M-GTA) revealed 24 concepts and 5 categories. We identified four stages of the process of kleptomania. The stages were “first theft,” “increasing frequency of stealing,” “pathological stealing” where the act of stealing was more beneficial than the stolen goods, followed by “automatic stealing” whenever they steal automatically in their favorite stores. We identified “breaking dependence on stealing” as the fifth category. In contrast, shoplifters for personal gain did not move into “pathological stealing.” Thus, it is assumed that the development of kleptomania involves a series of processes from starting to steal to addiction, then, it is assumed to enter a dependent stage from the stage of “pathological stealing.”

著者

大石 雅之 吉田 裕生 金 光男 柳沢 幸夫 杉山 了三

出版者

日本地質学会

雑誌

日本地質学会学術大会講演要旨

巻号頁・発行日

vol.101, 1994-09-20

著者

大野 希一 山川 修治 大石 雅之 高橋 康 上野 龍之 井田 貴史

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.50, no.6, pp.535-554, 2005-12-30

被引用文献数

1

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A cloud height generated by a volcanic eruption reflects the immensity and/or magnitude of the eruption; thus a measuring of the height's temporal variation during the event is very significant in judging whether the activity will become violent or decline. However, when a volcanic eruption occurs during bad weather, we must take information about the cloud's height by means of the pyroclastic deposits. In general, the total time taken for pyroclastic materials to be ejected and deposited at a given distance from the source vent can be divided into three parts as follows : the time for the eruption cloud to ascend and reach its neutral buoyancy level (T_1); the time for the pyroclastic materials to be transported laterally by the eruption cloud (T_2); and the time for pyroclastic materials to fall and be deposited on the ground (T_3). Since T_3 can be calculated from the settling velocity of pyroclastic materials, if the time that the pyroclastic materials fell at a given locality was observed and a given value for T_1 is assumed, the most suitable wind velocity to explain T_2 can be determined. Thus the height at which pyroclastic materials separate from the eruption cloud can be determined by using the vertical profile of wind velocity around the volcano. These ideas were applied to the eruption occurred at 19:44 (JST) on September 23, 2004, at the Asama volcano, which produced a pyroclastic fall deposit with a minimum weight of 7.2×10^6kg. Because this eruption occurred in bad weather, the pyroclastic materials fell as mud raindrops that were aggregate particles saturated by the rainwater. Based on the depositional mass, the number of impact marks of the mud raindrops in the unit area, and the apparent density and the equivalent diameter of these drops during their fall was estimated to be 2.2-3.1mm, which is consistent with the grain-size distribution of pyroclastic materials. According to some experienced accounts, mud raindrops several millimeters in diameter fell at 20:03 in the Kitakaruizawa area (about 9km north-northeast from the source). Assuming 2-5 minutes for T_1 and 11.5-12.0m/s of average lateral wind velocity, the height at which the mud raindrops separated from the eruption cloud can be estimated at 3,430-3,860m (3,610m on average). From this conclusion, the transportation and depositional process of the pyroclastic materials generated on September 23, 2004, at the Asama volcano can summarized as follows : the explosion occurred at 19:44 and the eruption cloud rose to 3,610m while blowing 2.49km downwind from the source. The cloud moved laterally for 4.51km with generating raindrops. At 19:54, mud raindrops separated from the cloud 7.0km north-northeast from the source, then fell to the ground at 20:03 after being blown 2.0km downwind by a lateral wind.

著者

大石 雅之

出版者

岩手県立博物館

雑誌

岩手県立博物館研究報告 (ISSN:02886308)

巻号頁・発行日

no.15, pp.1-10, 1997

著者

大石 雅之

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.6, pp.1237-1246, 2009-12-25 (Released:2010-03-23)

参考文献数

19

被引用文献数

1 4

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Azumaya Volcano is a stratovolcano located slightly at the back arc side of the volcanic front in central Japan. Previous studies led to the publication of a geologic map and the K-Ar age of some lavas, but the stratigraphic relationships of the volcanic products and their eruptive history are still unclear. Some tephras that possibly erupted from Azumaya Volcano have been found in the North Kanto region. But, there are relatively few descriptions of pyroclastic products. This study presents the lithological and petrographical characteristics of products from Azumaya Volcano, especially the refractive indices of phenocrysts, because these data are very important for identifying products and reconstructing eruptive history. This study examined the adequacy of the identification of tephras of the previous studies and whether the source of these tephras is Azumaya Volcano from the distribution of tephra and comparing mineral composition and refractive indices of orthopyroxene, plagioclase, hornblende, and cummingtonite phenocrysts in proximal products and distal tephras. Because the refractive indices of the phenocrysts in the products distributed in Azumaya Volcano have unique characteristics, refractive indices are useful for identifying and correlating products. Distal tephras correlated in previous studies have similar characteristics, increasing the probability that the source of the SgP.2 tephra bed is the Azumaya Volcano. In addition, the volume of the SgP.2 tephra bed was calculated to be 0.85 km3 dense-rock equivalents (DRE) using its distribution.

著者

山田 格 Chou Lien-Siang Chantrapornsyl Supot Adulyanukosol Kanjana Chakravarti Shyamal Kanti 大石 雅之 和田 志郎 Yao Chou-Ju 角田 恒雄 田島 木綿子 新井 上巳 梅谷 綾子 栗原 望

出版者

国立科学博物館

雑誌

国立科学博物館専報 (ISSN:00824755)

巻号頁・発行日

vol.44, pp.1-10, 2006

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台湾,タイ,インドの研究施設に保存されている中型ナガスクジラ属鯨類標本22点を調査し,骨格の形態学的特徴から,ミンククジラBalaenotera acutorostrata 4点,カツオクジラB. edeni 7点,ニタリクジラB. brydei 1点,ツノシマクジラB. omurai 10点を確認した.1970年代以来議論は提起されていたもののWada et al.(2003)が記載するまで不明瞭であったツノシマクジラの標本点数が相対的に多かったことは特筆に値する.本研究の結果は,これまで混乱が見られたいわゆる「ニタリクジラ類」の分類学的理解を解きほぐすものである.さらにこの混乱を完全に解決するためには,とくにカツオクジラのホロタイプ標本の分子遺伝学的調査が強く望まれる.