International Research Fellowship Program: Determining Bedrock Incision Rates using Cosmogenic Isotope \3He\ Analysis to Chronologically Constrain the Wetland Development Cycle in

国际研究奖学金计划：使用宇宙成因同位素 3He 分析确定基岩切割率，以按时间顺序限制湿地发展周期

• 批准号: 0754345
• 负责人: Amanda Keen-Zebert
• 金额: $ 21.54万
• 依托单位: Keen-Zebert Amanda K
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-05-01 至 2010-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0754345&HistoricalAwards=false
• 关键词: International; Research; Fellowship; Program; Determining

0754345Keen-ZebertThe International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.This award will support a twenty-four month research fellowship by Dr. Amanda Keen-Zebert to work with Dr. Stephen Tooth at the University of Wales, Aberystwyth in the UK.Wetlands are a focus of conservation efforts worldwide. However, geomorphological wetland research has been limited. In the Highveld of South Africa, the relationship between alluvial and bedrock river processes has consequences on the stability of wetlands that are an important water resource in a subhumid to semiarid area. The researchers in this project are investigating the long term development and sedimentological factors that effect wetland development and stability in South Africa. The researchers are adding a chronological element to a conceptual model of wetland development in the region that suggests that the progression from exhumation to breeching of dolerite intrusions into less resistant sedimentary rock controls the cycle of wetland development. By determining the bedrock incision rates through the dolerite intrusions using cosmogenic isotope analysis (CIA) and the timing of floodplain development through optically stimulated luminescence (OSL), it is possible to add long term chronological constraint to the conceptual model of wetland development. The improvement of the model will increase the understanding of river development in southern Africa, as well as the understanding of alluvial bedrock rivers and the interaction between alluvial and bedrock processes. Current wetland rehabilitation efforts in southern Africa are directed at human causes of degradation. If the degradation of these wetlands is structurally geomorphic in nature, then management strategies need adjustment. The information gained in this study will benefit wetland conservation and rehabilitation programs in South Africa.

[0754345]国际研究奖学金计划使美国科学家和工程师能够到国外进行9至24个月的研究。该计划的奖励为联合研究提供了机会，并利用独特或互补的设施、专业知识和国外的实验条件。该奖项将支持Amanda Keen-Zebert博士与英国阿伯里斯特威斯威尔士大学的Stephen Tooth博士进行为期24个月的研究。湿地是世界范围内保护工作的重点。然而，对地貌湿地的研究却十分有限。在南非高原，冲积和基岩河流过程之间的关系对湿地的稳定性产生影响，湿地是半湿润至半干旱地区的重要水资源。该项目的研究人员正在研究影响南非湿地发展和稳定的长期发展和沉积学因素。研究人员在该地区湿地发展的概念模型中加入了时间因素，该模型表明，从挖掘到侵入的白云岩进入抵抗力较弱的沉积岩的过程控制着湿地发展的周期。通过宇宙成因同位素分析（CIA）和光激发光技术（OSL）确定斑岩侵入岩的基岩切割速率，为湿地发育的概念模型增加长期的时间限制。该模型的改进将增加对南部非洲河流发展的认识，以及对冲积基岩河流和冲积基岩过程之间相互作用的认识。南部非洲目前的湿地恢复工作针对的是造成退化的人为原因。如果这些湿地的退化本质上是结构性的地貌性的，那么管理策略需要调整。本研究获得的信息将有利于南非的湿地保护和恢复计划。