テーマ
Great Barrier Reef environmental changes: the last deglacial sea level rise in the South Pacific: offshore drilling northeast Australia
航海期間
2010年2月11日~4月6日
掘削船
Mission Specific Platforms/ESO
(Greatship Maya)

掘削地点
Onshore Science Party (OSP) @ Bremen Core Repository
2010年7月2日~7月16日
J-DESC推薦の参加研究者
氏名(※はOffshoreにも参加) | 所属(参加時) | 役割 |
横山祐典※ | (東京大学大気海洋研究所) | Co-chief Scientist |
井上麻夕里 | (東京大学大気海洋研究所) | Paleoclimate Specialist |
井龍康文 | (名古屋大学) | Coral Specialist |
管 浩伸 | (岡山大学) | Sedimentologist |
鈴木 淳※ | (産業技術総合研究所) | Paleoclimate Specialist |
藤田和彦 | (琉球大学) | Micropaleontologist (Foraminifera) |
ESAT, Tezer | (東京大学大気海洋研究所) Asian Participation枠 |
Dating Specialist |
HUMBLET, Marc | (東京大学大気海洋研究所) | Coral Specialist |
航海の目的
The timing and course of sea-level rise during the last deglaciation is an essential component for understanding the dynamics of large ice sheets and their effects on Earth’s isostasy. Moreover, the disappearance of glacial ice sheets was responsible for dramatic changes in the freshwater fluxes to the oceans, which disturbed ocean thermohaline circulation and, hence, global climate. Coral reefs are excellent sea-level indicators, and their accurate dating by mass spectrometry is critical for constraining the timing, rate and amplitude of deglaciation events and thus for understanding of the mechanisms driving glacial?interglacial, millennial and centennial cycles.
Furthermore, scleractinian coral colonies can monitor seasonal sea-surface temperatures (SSTs) and record past SSTs. So far, the only published sea-level and climate record that encompasses the whole deglaciation is based on offshore drilling of Barbados fossil coral reefs which overlie an active subduction zone, implying that the apparent sea-level record may be biased by tectonic movements. Tahiti and the Australian Great Barrier Reef represent key locations to address these problems as they are in tectonically inactive areas far away from glaciated regions.
Submerged fossil coral reefs are common but poorly studied features along the shelf edge of the Great Barrier Reef. At several key sites along 5 transects in 3 regions it is proposed to drill offshore shallow penetration drill holes using a Mission Specific Platform. The drilling targets include the successive reef terraces, relict reefs and the slope, from ~40 to 200 m water depth.
The scientific aims of the project are to:
- Establish the course of sea-level rise during the last deglaciation (~20-10 ka).
- Reconstruct the nature and magnitude of seasonal-millennial scale climate variability (ie. sea surface temperature and sea surface salinity).
- Determine the biologic and geologic response of the Great Barrier Reef to abrupt sea-level and climate changes in the past as a possible template to improve predictions of ecosystem response to future global climate changes.
関連ページ
年 | 著者/タイトル | 出版物 |
2011 | Yokoyama, Y., Webster, J.M., Cotterill, C., Braga, J.C., Jovane, L., Mills, H., Morgan, S., Suzuki, A., and the IODP Expedition 325 Scientists
IODP Expedition 325: Great Barrier Reef Reveals Past Sea-Level, Climate and Environmental Changes Since the Last Ice Age |
Scientific Drilling |
2010 | Webster, J.M., Yokoyama, Y., Cotterill, C., and the Expedition 325 Scientists
Great Barrier Reef Environmental Changes |
Proceedings of the IODP |
Expedition 325 Scientists
Great Barrier Reef environmental changes: the last deglacial sea level rise in the South Pacific: offshore drilling northeast Australia |
IODP Preliminary Report | |
2009 | Webster, J.M., Yokoyama, Y., and Cotterill, C.
Great Barrier Reef environmental changes: the last deglacial sea level rise in the South Pacific: offshore drilling northeast Australia |
IODP Scientific Prospectus |
ESO発表(2010年7月19日)
7月2日から16日まで、統合国際深海掘削計画(IODP)の第325次研究航 海「オーストラリアグレートバリアリーフにおける環境変動研究調査」の陸上基礎分析研究フェーズとして、ブレーメン海洋コアセンターにおいて、9カ国28 名の科学者が化石サンゴコアの解析を行いました。第325次研究航海は、特定任務掘削船による沖合掘削フェーズ(2010年2月から4月にかけて実施)と 陸上施設における基礎分析研究フェーズ(OSP)の2期に分かれており、沖合掘削フェーズでは水深42mから167m の地点から、34地点を掘削し、総計225mのコア試料を採取しました。
第325次研究航海の国際研究チームを率いる共同首席研究員の横山祐典 准教授(東京大学)とJody Webster 准教授(シドニー大学)は、グレートバリアリーフからの掘削コアが示す、過去の海水準、気候変動、そしてサンゴ礁の環境応答の解明につながる発見の第一報 を発表しました。
>>リリース文全文(英文)
文部科学省発表
統合国際深海掘削計画(IODP)における研究航海の開始について
~オーストラリアグレートバリアリーフにおける環境変動研究調査~(2009年12月14日)
その他の発表
ECORDメディアリリース「Unlocking the Secrets of Sea- Level Change
– Great Barrier Reef Expedition starts -」(2010年2月11日発表)