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

飓风丽塔在路易斯安那州沿海沼泽的风暴潮沉积特征和保存。项目摘要(1)技术描述：提出研究路易斯安那州沿海沼泽飓风丽塔的风暴潮沉积，以帮助回答两个具有重要社会意义的问题：飓风风暴潮对长期沿海沼泽沉积的影响有多大？还有，风暴潮沉积物和沿海沼泽的海啸沉积物有区别吗？为了解决第一个问题，建议对风暴潮沉积物在沉积后的几周内进行取样和表征，而沉积物将在沼泽表面，清晰可识别，相对不受侵蚀和生物扰动的干扰。同样的沉积物将在1年半后重新调查，以确定有多少沉积物被纳入沼泽，并有助于长期的沼泽沉积。这一贡献的重要性将通过将风暴潮沉降与从铯-137年代测定中获得的底层沼泽的长期平均沉降率进行比较来确定。第二个问题将通过确定风暴潮沉积物内部的沉积结构是否支持这样的假设来解决，即海啸沉积物可以通过与海啸波列相一致的富含沉积物的水的多次脉冲的内部证据来识别。这种结构在海啸沉积物中很常见，但在风暴潮沉积物中显然不存在。(2)非技术描述：飓风引发的风暴潮沉积可能是沿海沼泽生长的一个重要但鲜为人知的机制。这项研究的数据将提高我们对这一机制的理解，并提高我们准确、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易受全球变暖导致的海平面上升影响的沿海沼泽的命运将非常重要。更好地了解风暴潮沉积物对长期沼泽沉积的潜在影响将导致对长期沼泽生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生态和商业上重要的栖息地将是重要的。海啸沉积物的可靠识别是有效估计地震复发间隔和进行海啸减灾研究的必要条件。这个项目也将有助于整合研究和教育，因为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。该项目的成果将广泛传播，以各种方式增进对科学和技术的了解，使科学研究人员、决策者和广大公众都能接触到。预计该项目将在几次会议上发表演讲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.