文章基本信息

标题：GEOLOGICAL INVESTIGATION OF PALAEOTSUNAMIS IN THE SAMOAN ISLANDS: INTERIM REPORT AND RESEARCH DIRECTIONS
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作者：Shaun Williams ; James Goff ; Johnny Ah Kau 等
期刊名称：Science of Tsunami Hazards
印刷版ISSN：8755-6839
出版年度：2013
卷号：32
期号：3
页码：156-175
出版社：Tsunami Society International
摘要：The September 29, 2009 Samoa Tsunami provided the opportunity to sample the sediments deposited in the Samoan Islands landscape by the tsunami. Analysing the characteristics of the sediment deposits using an established suite of diagnostic criteria, and assessing how they differ from cyclone deposits enables the identification and dating of similar events in the geologic record. This helps to better understand the long-term frequency and likely magnitude of these events. Here we report on a pilot palaeotsunami field-sampling investigation carried out in 2010 at selected sites on Upolu and Savaii Islands in the Independent State of Samoa, and on Ta'u Island inAmerican Samoa. We present empirical stratigraphic data for the investigated sites, and we demonstrate the existence of high energy marine inundation deposits at some of these sites which were laid down by past tsunamis and/or cyclones. We review and discuss the analytical outcomes, as well as summarise the overarching directions of this research. We propose that there is a need for this study to continue and for such studies to be carried out in other islands in the Pacific. By doing this, we can build onthe sparse palaeotsunami database in the region, thereby helping to improve our understanding of the long-term frequency, impact distribution, and likely magnitude of these events. Further, we can start assessing their likely sources and the long-term risk these hazards pose to coastal cities and communities in the Pacific.