Flux and Fate of Sediment from Small Mountainous Rivers to the Continental Margin: The Gulf of Alaska Example

从小山河流到大陆边缘的沉积物通量和归宿：阿拉斯加湾的例子

• 批准号: 9222503
• 负责人: Susan Henrichs
• 金额: $ 21万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-04-15 至 1998-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9222503&HistoricalAwards=false
• 关键词: Flux; Fate; Sediment; Small; Mountainous

Abstract: ATM-9223114, PI-Henrichs, University of Alaska, "Flux and Fate of Sediment and Water from Small, Mountainous Rivers to the Continental Margin: The Gulf of Alaska Example": Small rivers charging directly from mountains into the ocean carry greater sediment loads than commonly envisioned, a relatively great percentage of which may escape to deeper waters during high stands of sea level. This award supports a study of the flux of Holocene fluvial sediment into the Gulf of Alaska, whose generally small tributary rivers are collectively the largest supplier of sediment from North America. Alaskan rivers are relatively uninfluenced by human activities, although glacial activity has resulted in higher sediment yields than noted for other rivers with similar drainage areas. The investigation will employ high-resolution seismic profiling for the identification of sediment accumulation and discharge patterns on the shelf and slope, and to trace individual sediment layers derived from episodic (flood) events. Sedimentological data will help define the escape routes/processes, and a variety of radiometric datings will show frequency of occurrence and rates of accumulation. Measurements of total organic carbon and total nitrogen, del13C, del15N, and lignin will be used to determine the amount and source of organic matter accumulating in the sediments. Contemporaneous oceanographic processes controlling strata formation will also be evaluated. This information should help in the interpretation of the older strata observed by seismic profiling and coring.

摘要：ATM-9223114， PI-Henrichs，阿拉斯加大学，“从山地小河流到大陆边缘的泥沙和水的通量和命运：阿拉斯加湾的例子”：直接从山区流入海洋的小河流携带的泥沙比通常想象的要多，其中相当大的比例可能在海平面高的时候流入更深的水域。该奖项支持对全新世河流沉积物流入阿拉斯加湾的研究，阿拉斯加湾的小支流通常是北美最大的沉积物供应者。阿拉斯加河流相对不受人类活动的影响，尽管冰川活动导致的沉积物产生量高于其他具有类似流域的河流。调查将采用高分辨率地震剖面来识别大陆架和斜坡上的沉积物堆积和排放模式，并追踪由偶发性（洪水）事件产生的单个沉积层。沉积学数据将有助于确定逃逸路线/过程，各种放射性定年法将显示出发生的频率和积累的速度。总有机碳和总氮、del13C、del15N和木质素的测量将用于确定沉积物中积累的有机质的数量和来源。同时还将评价控制地层形成的同期海洋过程。这些信息将有助于解释地震剖面和取心所观察到的较老地层。