SGER: Search for a Indian Ocean Paleotsunami Record Along the Andaman Coast, Thailand

正如2004年12月的海啸痛苦地表明的那样，印度洋没有海啸预警系统。在这一事件之前没有建立预警系统的动力，因为印度洋这一地区以前发生海啸的已知历史或地质记录很少，因此没有对这类事件发生频率的估计。在陆地上，2004年的海啸在各种沼泽环境中沉积了沙子，鉴于苏门答腊海沟靠近西部，似乎很有可能是史前大海啸影响了这一区域，并留下了类似的沉积记录。2004年海啸沉积物的存在为寻找这样的海啸记录提供了一个独特的机会。投资促进局将开展一个项目，在普吉岛安达曼海岸寻找合适的沉积圈闭并取心，这些圈闭本应捕捉到苏门答腊海沟地震引发的海啸的长期记录。然而，他们确定的沿海遗址都位于快速发展的旅游区，这些地区的度假胜地在海啸后加速发展，现在有可能摧毁最有希望的古海啸遗址。度假村的开发使机票便宜，通常也使人们更容易到达(道路、基础设施等)--但在这种情况下，它也威胁到研究地点本身。该项目正在2004年洪水淹没带内确定合适的、主要是泥泞的沉积环境，在那里最有可能保存海啸沉积物。每个地点的地表地质和地形都是使用差分GPS绘制的。从这些地点采集的岩心是使用Livingstone活塞式取样器收集的，该取样器能够捕获长达5米的岩心。使用各种沉积、化学和物理标准对岩心进行分析，以识别任何古太阳海啸沉积，并记录该地区的全新世历史。从岩心中提取关键样品进行14C测年。该项目将验证普吉岛沿海沼泽中是否存在古太阳海啸沉积，并提供安达曼地区全新世沉积年代学的初步资料。2004年海啸对泰国的影响是毁灭性的。了解未来海啸危险的努力取决于对史前海啸年表的了解。特别是，以前海啸的记录将有助于消除这是一次性事件的神话，并为人口稠密和迅速发展的安达曼海岸的海啸灾害准备工作提供动力。除了适当的国际同行评议期刊外，私人投资机构还将在泰国当地出版物上发表结果，并在泰国的会议上公布结果。至少有一名CSUF学生将参与核心分析。泰国学生(由朱拉隆功大学资助)也将参与实地工作。这将是一个与泰国科学家合作的项目，他们将在全新世沉积物采样和分析方面获得新的专业知识，而这是他们目前缺乏的专业知识。国际善意、理解和合作的继续将对CSUF和泰国的这一项目产生重大影响。

As the December 2004 tsunami made painfully clear, there is no tsunami warning system in the Indian Ocean. There has been no impetus for a warning system prior to this event because there are very few known historical or geologic records of previous tsunamis in this part of the Indian Ocean, and therefore no estimates on the frequency of such events. Onshore, the 2004 tsunami deposited sand in a variety of marshy environments, and, given the proximity of the Sumatran trench to the West, it seems highly likely that large pre-historic tsunamis affected this region and left behind similar sedimentary records. The existence of the 2004 tsunami deposit provides a unique opportunity to find such a record of these tsunamis. The PIs will carry out a project to locate and core suitable sedimentary traps along the Andaman coast of Phuket Island - traps that should have captured a long term record of tsunamis derived from earthquakes along the Sumatran Trench. However, the coastal sites they have identified all lie within rapidly developing tourist areas where resort development has accelerated in the post-tsunami period, and now threatens to destroy the most promising paleotsunami sites. Resort development makes airfares cheap and usually makes for easier access (roads, infrastructure, etc.) - but in this case, it also threatens the study sites themselves.This project is identifying suitable, primarily muddy, sedimentary environments within the 2004 inundation zone where preservation of tsunami deposits is most likely. The surficial geology and topography at each site is mapped using differential GPS. Cores from these sites are collected using a Livingstone piston corer capable of capturing cores up to 5 m long. Cores are analyzed using a variety of sedimentary, chemical and physical criteria to identify any paleotsunami deposits, and to document the Holocene history of the region. Key samples are extracted from the cores for 14C dating. This project will verify the existence of paleotsunami deposits in coastal marshes of Phuket and provide a preliminary Holocene depositional chronology for the Andaman region. The impact of the 2004 tsunami was devastating to Thailand. Efforts to understand the future tsunami hazard depend on knowledge of the prehistoric tsunami chronology. In particular, the documentation of previous tsunamis will help dispel the myth that this was a one-time-ever event, and lend momentum to tsunami hazard preparation along the densely populated and rapidly developing Andaman coast. In addition to the appropriate international peer-reviewed journals, the PIs will publish results in local Thai publications, and present the results at conferences in Thailand. At least one CSUF student will be involved in the core analyses. Thai students (funded by Chulalongkorn University) will also participate in the field work.This will be a collaborative project with Thai scientists who will gain new expertise in the sampling and analysis of Holocene sediment, an expertise they currently lack. The continuation of international goodwill, understanding and cooperation will be a significant impact of this project both at CSUF and in Thailand.