Acquisition of an Automated Laser Diffraction Particle Size Analyzer at the University of Massachusetts

该补助金支持购买带有自动样品制备和引入装置的激光衍射粒度分析仪。 该仪器将支持马萨诸塞州阿默斯特大学的教师和学生的研究，该研究需要确定沉积物和土壤中的细粒粒度分布。 粒度分析是支持沉积学、自然灾害、古气候学、地貌学和水文学研究的基本工具。 该收购将支持极端事件期间河流和河口的沉积物输运研究、北极古气候调查和断裂带材料力学特性。 学生将接受仪器程序培训，仪器将服务于新英格兰的区域机构。 此次收购还将支持教师的外联工作，使区域K-12和社区大学的学生参与社会相关的古环境研究。 这种支持与NSF的使命是一致的，即促进科学进步和促进国家健康，繁荣和福利，因为有针对性的研究旨在了解陆地和海洋沉积记录中记录的影响美国东北部的历史飓风记录，研究湖泊沉积物中记录的地球气候动态，以及收购对培训下一代科学工作者的影响。极端洪水期间流体和沉积物输运的基本机制。 为了填补这一知识空白，马萨诸塞州阿默斯特大学的沉积学实验室和弗吉尼亚理工大学的同事们目前正在使用历史洪水的沉积模式来验证和告知极端流量下沉积物动力学的数值模拟。 沉积物的粒度分布后障壁沼泽和池塘中的沉积物可变化3个数量级，从海岸的粗沙滩砂和砾石到向陆地延伸的细粒泥帘。 绘制这些沉积物的空间趋势有助于了解极端洪水事件期间沉积物运移的物理学。 激光粒度分析仪还将用于识别嵌入细粒湖泊和泻湖沉积物中的粗粒风暴沉积物，以进一步扩展我们对史前飓风事件的了解，从而更好地了解飓风灾害的可能性。 粒度分析仪还将通过检查湖泊沉积物粒度的古记录作为冰川前进和后退的代表，帮助研究高纬度冰川历史。

This grant supports acquisition of a laser diffraction particle size analyzer with automated sample preparation and introduction devices. The instrument will support faculty and student research at the University of Massachusetts Amherst that requires determination of fine grained particle size distributions in sediments and soils. Grain size analysis is a fundamental tool supporting research in sedimentology, natural hazards, paleoclimatology, geomorphology, and hydrology. Studies of sediment transport in rivers and estuaries during extreme events, Arctic paleoclimate investigations, and fault zone material mechanical properties will be supported by the acquisition. Students will be trained in instrumental procedures and the instrument will serve regional institutions in New England. The acquisition will also support faculty outreach efforts to engage regional K-12 and community college students in societally relevant paleoenvironmental research. This support is congruent with NSF's mission of promoting the progress of science and advancing the national health, prosperity and welfare given the relevance of targeted research aimed at understanding records of historical hurricanes affecting the U.S. Northeast as recorded in the terrestrial and marine sedimentary records, studies of Earth's climate dynamics as recorded in lake sediments and the impact of the acquisition on training the next generation scientific workforce.Significant uncertainty remains regarding the fundamental mechanisms of fluid and sediment transport during extreme flooding. To fill this knowledge gap, the sedimentology lab at the University of Massachusetts Amherst and colleagues at Virginia Tech are currently using patterns in deposition from historical floods to validate and inform numerical simulations of sediment dynamics under extreme flows. Grain size distribution of sediment?s in back barrier marshes and ponds can vary by 3 orders of magnitude, from coarse beach-derived sand and gravel at the coast to fine-grained mud drapes at their landward extents. Mapping spatial trends in these deposits assist in understanding the physics of sediment transport during extreme flood events. The laser particle size analyzer will also be used to identify coarse-grained storm deposits embedded within fine-grained lake and lagoon sediments to further extend our knowledge of pre-historic hurricane events and therefore better understand the probability of hurricane hazards. The particle size analyzer will also aid in studies of high latitude glacial history by examining the paleorecords of lake sediment grain size as a proxy of glacial advance and retreat.