FIELD SURVEY ABOUT FORMATION OF CORAL CAYS AND TRANSPORT OF CORAL GRAVELON BALLAST ISLAND

• SANUKI Hiroshi

  五洋建設（株）技術研究所

• TAJIMA Yoshimitsu

  東京大学大学院工学系研究科

• KOTOURA Tsuyoshi

  五洋建設（株）技術研究所

• MAEDA Yuuji

  五洋建設（株）技術研究所

• KAYANNE Hajime

  東京大学大学院理学系研究科

Bibliographic Information

Other Title

• 州島の形成とサンゴ砂礫の移動に関する現地調査

Abstract

 Coral cays formation mechanism has various field surveys, experiment, and numerical simulations, but observation data for transport feature of coral gravel and topographic change is almost less. In this study, we conducted field survey in ballast island on northern reef of Iriomote Island which is formed by only coral gravels. Then, we discuss about external force and transport feature of coral gravel in the reef. As a result, we understand that external force of coral gravel transport is caused by the waves than the flow on the reef and Shields number is around 0.03, these results correspond with the past study. The movement of colored coral gravel showed that wave from east and south gathered coral gravel in the reef to ballast island. Then, we measured the amount of gravel which trapped in the sediment-trap on lower end of the reef slope. Thus, coral cays are formed and maintained by transport of gravel to island and flow out to reef slope.

Journal

• Journal of Japan Society of Civil Engineers, Ser. B3 (Ocean Engineering)

  Journal of Japan Society of Civil Engineers, Ser. B3 (Ocean Engineering) 72 (2), I_43-I_48, 2016

  Japan Society of Civil Engineers

Keywords

• coral reef
• ballast island
• wave observation
• steep slope reef
• gravel transport

Details

• CRID: 1390282680329532288
• NII Article ID: 130005263365
• DOI: 10.2208/jscejoe.72.i_43
• ISSN: 21854688
• Web Site: https://www.jstage.jst.go.jp/article/jscejoe/72/2/72_I_43/_pdf
• Text Lang: ja
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed