<紀要論文>
玄界灘沿岸に発達する礫浜の形成機構

作成者
本文言語
出版者
発行日
収録物名
開始ページ
終了ページ
出版タイプ
アクセス権
JaLC DOI
概要 A number of small gravel beaches are distributed on the Genkainada coast, North Kyushu. These gravels are monomictic, composed mainly of basaltic rocks. Such beaches provide a good example for the stu...dy of formation mechanisms of gravel beaches, which have been little understood. In this study, mechanisms of preservation of gravel as well as supplying systems and provenances of gravels were investigated at seven beaches of Tsuyazaki, Aino Island, Keya, Hime Island, Taka Island, Kashiwa Island and Nanatsu-gama, all located along the north coast of Kyushu. Amomg them, the Tsuyazaki and Keya coasts and Aino Island were chosen for detailed observations of the occurrence of gravels. Judging from lateral changes of the roundness, clast sizes and their sorting, most of gravels from these beaches were successfully traced to their source points, which are composed of talus deposits from Pliocene basaltic lavas. Gravels are, in general, finally buried at the distal points by sands. According to observations, boulders and large cobbles are moved over several meters only during very strong waves, measuring more than 2. 5m of wave height. Those strong waves with the trend of wave directions toward SE to E are observed predominantly in the winter season, which control the morphology of gravel beaches. Based on a 15 to 30 year-long time-lapse check on air-photographs, it seems to take much longer period than several tens of years for significant changes of the form of gravel beaches on the Genkainada coast.続きを見る
目次 I. はじめに
II. 玄界灘沿岸に分布する礫浜の概要
III. 調査方法
IV. 礫浜の調査結果
V. 考察
VI. まとめ

本文ファイル

pdf 1801_p085 pdf 1.64 MB 863  

詳細

PISSN
NCID
レコードID
登録日 2021.10.18
更新日 2022.10.25

この資料を見た人はこんな資料も見ています