Field survey on the 1998 tsunami in the northwestern area of Papua New Guinea

1998年巴布亚新几内亚西北地区海啸实地调查

• 批准号: 10400010
• 负责人: KAWATA Yoshiaki
• 金额: --
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 无数据
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10400010/
• 关键词: Tsunami earthquake; Giant tsunami; Field survey; Numerical simulation; Energy concentration; Lagoon; Critical flow; Sand bank; 海底地滑り; 遡上; 越流; 余震観測; 国際協力

The first investigation on the tsunami caused by the earthquake offshore northwestern coast of Papua New Guinea (PNG) was carried out by the International Tsunami Survey Team (ITST) during the period of 31 July to 7 August 1998. On the evening of Friday 17 July a massive tsunami swept across the sand bar that forms the outer margin of Sissano Lagoon, west Sepik, PNG. Initial media reported that the tsunami struck west of the town of Aitape in the west Sepik province, hitting at least four villages. And the was 7 - 10 m and that up to 3,000 persons were killed or missing. This seemed to be an unusually damaging tsunami given the size of the earthquake (M=7). Members of the ITST decided that a field survey was necessary as soon as possible to try and determine the true value of the maximum run-up and to accurately map the run-up distribution along the coast. The survey to the damaged area confirmed the 7 - 10 m wave heights reported and found the place where the waves were larger up to 15 m and extreme overland flow velocities of 10 to 15 m/s. The severe damage and extreme wave heights were confined to a relatively short (30km) stretch of coast between Aitape and Sissano Villages and specially large along the sand bar the outer margin of Sissano Lagoon. These suggest that tsunami energy is concentrated in this narrow region. Although a tsunami is to be amplified in V-shaped bay, peninsula, island and ridge, the coastal line in Sissano is straight and the contour lines of water depth are almost parallel. Extremely large tsunami than estimated by an earthquake (M=7) might be caused by not a local bottom topography but a tsunami generation. Eyewitness of a loud bang, hot water, bubbles and foul smell suggest sea landslide or a gas explosion offshore triggered by the earthquake as a secondary mechanism of tsunami generation. Further field investigation and research on it are required to solve a riddle of the tsunami generation.

在1998年7月31日至8月7日，国际海啸调查团队（ITST）进行了首次对巴布亚新几内亚（PNG）地震西北海岸（PNG）造成的海啸调查。最初的媒体报道说，海啸袭击了西塞皮克省Aitape镇以西，至少袭击了四个村庄。这是7-10 m，最多3,000人被杀或失踪。考虑到地震的大小，这似乎是一种异常破坏的海啸（M = 7）。 ITST的成员决定，必须尽快进行现场调查，以尝试确定最大升级的真实价值，并准确地绘制沿海岸的升级分布。对受损区域的调查证实了报告的7-10 m波高度，并发现了波浪较大至15 m的位置，而极端的陆上流速为10至15 m/s。严重的损坏和极端波高的高度仅限于Aitape和Sissano村庄之间的相对较短（30公里）的海岸，沿Sissano Lagoon的外部边缘沿着沙杆特别大。这些表明海啸能量集中在这个狭窄的区域。尽管要在半岛，岛屿和山脊的V形海湾放大海啸，但西萨诺的沿海线是笔直的，水深的轮廓线几乎是平行的。地震（M = 7）估计的极大海啸可能不是由局部底部地形而是海啸产生引起的。大声的爆炸，热水，气泡和臭味的目击者表明，地震触发的海洋滑坡或瓦斯爆炸是海啸一代的次要机制。需要进一步的现场调查及其研究来解决海啸一代的谜语。

项目成果

Imamura、F: "The Sissano Tsunami caused by the earthquake in PNG and the riddle of its generation"Newsletter of Natural Hazards Society. Vol.3,issue4. (1999)

Imamura, F：“巴布亚新几内亚地震引发的西萨诺海啸及其一代之谜”自然灾害协会通讯，第 3 卷，第 4 期（1999 年）。

Kawata,K., B.Benson, J.Borrero, J.Borrero, H.Davies, W.P.deLange, F.Imamura, H.Letz, J.Nott: "Tsunami in Papua New Guinea was as intense as first thought"EOS, Transactions, AGU. Vol.80,No.9. 101,104-105 (1999)

Kawata,K.、B.Benson、J.Borrero、J.Borrero、H.Davies、W.P.deLange、F.Imamura、H.Letz、J.Nott：“巴布亚新几内亚的海啸与最初想象的一样强烈”EOS

Fujimasa, K., et al.: "Discussion on the tsunami source of the 1998 PNG"Coastal Engineering in Japan. Vol.46. 381-385 (1999)

Fujimasa, K. 等人：“1998 年巴布亚新几内亚海啸来源的讨论”日本海岸工程。

河田恵昭、高橋智幸、今村文彦、松冨英夫、藤間功司、都司嘉宣、松山昌史: "1998年パプアニューギニア地震津波の現地調査"海岸工学論文集. 第46巻. 391-395 (1999)

Yoshiaki Kawata、Tomoyuki Takahashi、Fumihiko Imamura、Hideo Matsutomi、Koji Fujima、Yoshinobu Tsuji、Masashi Matsuyama：“1998 年巴布亚新几内亚地震和海啸的实地调查”海岸工程论文第 46 卷。391-395（1999 年）

Matsutomi, H., et al.: "Survey of the 1998 PNG tsunami"Coastal Engineering in Japan. Vol.46. 376-380 (1999)

Matsutomi, H., et al.：“1998 年巴布亚新几内亚海啸调查”日本海岸工程。