| 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
|
| 巻 |
15巻
|
| 号 |
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
|
