RAPID: Tsunami deposits and coastal uplift near Concepcion, Chile before and after the major earthquake of February 27, 2010

RAPID：2010 年 2 月 27 日大地震前后智利康塞普西翁附近的海啸沉积和海岸隆起

• 批准号: 1036057
• 负责人: Lisa Ely
• 金额: $ 2.6万
• 依托单位: Central Washington University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2012-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1036057&HistoricalAwards=false
• 关键词: RAPID; Tsunami; deposits; coastal; uplift

On February 27, 2010 a catastrophic magnitude 9 earthquake and accompanying tsunami struck the coast of central Chile. The effects of this event were particularly devastating in the area surrounding Concepción, the second largest city in Chile. This project will precisely document the geomorphic and tectonic signatures of this earthquake and tsunami at several previously described study sites in the Concepción region. In 2009 and early 2010 the author and Chilean collaborators described and surveyed tsunami deposits and uplifted coastal marine platforms at 10 sites between 36.5°S to 38.5°S. Lat. The objectives of this project are twofold: 1) Investigate deposits and impacts of the 2010 tsunami at existing study sites containing geological and historical evidence of previous tsunamis in the Concepción area; and 2) Assess co-seismic and post-seismic land-level changes at existing study sites that underwent significant uplift in previous earthquakes. Field work will be conducted in two separate field excursions between May, 2010 and January, 2011. Field investigations will include mapping and surveying the erosional and depositional effects of the 2010 tsunami at the previously documented sites to compare the deposits from the 2010 tsunami with those from previous events; calibrate the sedimentary deposits with the observational data; assess the preservation potential of tsunami deposits in this environment; and use the 2010 deposits to guide the search for additional repositories where stratigraphic records of multiple paleotsunami deposits are likely to be preserved. At the locations of land-level changes the field objectives will be to resurvey heights of marine platforms that were uplifted during previous earthquakes and surveyed by our team in January, 2010; determine the amount of additional uplift in the 2010 earthquake; establish a baseline elevation for subsequent monitoring of post-seismic land-level changes; and compare locations and amount of uplift in the 2010 earthquake with that measured after the 1835 earthquake. This research has the potential to advance knowledge of the impacts, recurrence, and geological signatures of catastrophic events on the scale of the 2010 Chilean earthquake, which could lead to better preparation, education and decreased loss of life in similar coastal areas. The project will occasion U.S.-Chile collaboration that fosters mutual exchanges of knowledge and expertise. An accurate measurement of the effects of the recent tsunami and coastal uplift from the earthquake, together with the prior measurements, will enable a complete documentation of recurrence intervals of these events and the areas that are most affected. These data will be of great value in the rebuilding process for the communities devastated by the most recent event, and the investigation will have a sustainable presence where it will be most needed and useful.

2010 年 2 月 27 日，一场灾难性的 9 级地震和随之而来的海啸袭击了智利中部海岸。这一事件对智利第二大城市康塞普西翁周边地区的影响尤其具有破坏性。该项目将在康塞普西翁地区几个先前描述的研究地点精确记录这次地震和海啸的地貌和构造特征。 2009 年和 2010 年初，作者和智利合作者描述并调查了南纬 36.5° 至 38.5° 之间 10 个地点的海啸沉积物和隆起的沿海海洋平台。纬度。 该项目有双重目标： 1) 在现有研究地点调查 2010 年海啸的沉积物和影响，这些研究地点包含康塞普西翁地区先前海啸的地质和历史证据； 2) 评估在以往地震中经历过显着抬升的现有研究地点的同震和震后土地平面变化。实地工作将在 2010 年 5 月至 2011 年 1 月期间分两次单独的实地考察进行。实地调查将包括在先前记录的地点绘制和测量 2010 年海啸的侵蚀和沉积影响，以将 2010 年海啸的沉积物与之前事件的沉积物进行比较；用观测数据校准沉积物；评估该环境中海啸沉积物的保存潜力；并利用 2010 年沉积物来指导寻找可能保存多个古海啸沉积物地层记录的其他储存库。在陆地平面变化的位置，现场目标将是重新测量在之前的地震中抬升的海洋平台的高度，并由我们的团队于 2010 年 1 月进行了测量；确定2010年地震中的额外抬升量；建立基线高程，以便随后监测震后土地平面变化；并将 2010 年地震中的抬升位置和抬升量与 1835 年地震后测量的抬升量进行比较。这项研究有可能增进对 2010 年智利地震规模的灾难性事件的影响、复发和地质特征的了解，这可能会导致类似沿海地区更好的准备、教育和减少生命损失。该项目将促进美国与智利之间的合作，促进知识和专业知识的相互交流。准确测量近期海啸和地震造成的海岸隆起的影响，再加上之前的测量，将能够完整记录这些事件的复发间隔和受影响最严重的地区。这些数据对于遭受最近事件破坏的社区的重建过程将具有巨大价值，并且调查将在最需要和最有用的地方持续存在。