SGER: Character and preservation of hurricane Rita storm surge sedimentation in Louisiana coastal marshes.

项目摘要(1)技术描述：建议研究路易斯安那州沿海沼泽中飓风丽塔的风暴潮沉积，以帮助回答两个具有重大社会意义的问题：对长期的海岸沼泽沉积有多大意义，但飓风风暴潮的大量输入？风暴潮沉积与沿海沼泽地的海啸沉积有区别吗？为了解决第一个问题，建议在沉积后几周内对风暴潮沉积物进行采样和表征，而沉积物将位于沼泽表面，可以清楚地识别，并且相对不受侵蚀和生物扰动的干扰。同样的沉积物将在1.5年后重新测量，以确定有多少沉积物被并入沼泽，并对沼泽的长期沉积做出贡献。这一贡献的重要性将通过将风暴潮沉积与通过铯-137测年获得的底层沼泽的长期平均沉积速率进行比较来确定。第二个问题将通过确定风暴潮沉积中的内部沉积结构是否支持这样的假设来解决，即海啸沉积可以通过与海啸波列一致的多脉冲含沙水的内部证据来识别。这种结构在海啸沉积中很常见，但在风暴潮沉积中显然是不存在的。(2)非技术描述：飓风引发的风暴潮沉积可能是海岸沼泽生长的一个重要但知之甚少的机制。这项研究的数据将提高我们对这一机制的理解，以及我们准确和现实地预测沼泽生长的能力。更好地了解沼泽沉积对于研究全球变暖导致的易受海平面上升影响的沿海沼泽的命运将是重要的。更好地了解风暴潮沉积对长期沼泽沉积的潜在影响将导致对沼泽长期增长的更可靠和现实的预测。这种预测能力对于有效保护和管理这些具有生态和商业意义的重要栖息地将是重要的。为有效估计地震复发间隔时间和进行海啸减灾研究，需要可靠地确定海啸沉积物。该项目还将用于整合研究和教育，因为一名研究生研究助理将参与实地工作和实验室工作，并将该项目作为硕士论文的基础。将广泛传播这一项目的成果，以各种方式增进对科学和技术的了解，让科学研究人员、政策制定者和广大公众了解。预计该项目将导致几次会议发言和同行评议的期刊文章。

Character and preservation of Hurricane Rita storm surge sedimentation in Louisiana coastal marshes.Project Abstract(1) technical description:It is proposed to study storm surge deposits of Hurricane Rita in Louisiana coastal marshes to help answer two questions of significant societal importance: how significant to long-term coastal marsh sedimentation are episodic, but large inputs of sediment from hurricane storm surges? and, are storm surge deposits distinguishable from tsunami deposits in coastal marshes? To address the first question it is proposed to sample and characterize the storm surge deposits within weeks of deposition, while the sediments will be at the surface of the marsh, clearly identifiable and relatively undisturbed by erosion and bioturbation. The same deposits will resurveyed after 1.5 years to determine how much of the deposit is incorporated into the marsh and contributes to long-term marsh sedimentation. The significance of this contribution will be determined by comparing the storm surge sedimentation to long-term average sedimentation rates of the underlying marsh gained from cesium-137 dating. The second question will be addressed by determining if internal sedimentary structures within the storm surge deposits support the hypothesis that tsunami deposits can be identified by internal evidence of multiple pulses of sediment-laden water, consistent with a tsunami wave train. Such structures are common in tsunami deposits, but are apparently absent in storm surge deposits.(2) nontechnical description:Hurricane-derived storm surge sedimentation may be an important, but poorly understood mechanism of coastal marsh growth. Data from this study will improve our understanding of this mechanism and our ability to accurately and realistically predict marsh growth. Better understanding of marsh sedimentation will be important for studies of the fate of coastal marshes vulnerable to sea level rise caused by global warming.Better understanding of the potential impact of storm surge deposits on long-term marsh sedimentation will result in more reliable and realistic predictions of long-term marsh growth. This predictive capability will be important for the effective protection and management of these ecologically and commercially important habitats. Reliable identification of tsunami deposits is required for effective estimation of earthquake recurrence intervals and for tsunami hazard mitigation research. This project will also serve to integrate research and education, because a graduate research assistant will participate in fieldwork and laboratory work and will use the project as the basis for a master's thesis. The results of this project will be broadly disseminated to enhance scientific and technical understanding in a variety of ways, reaching scientific researchers, policy-makers and the public-at-large. It is anticipated that this project will result in several conference presentations and peer-reviewed journal articles.