Topographic Controls on the Generation of Elutriated Ash Clouds: II. Nature and Dynamics of Pyroclastic Density Currents

地形对淘析灰云生成的控制：II。

• 批准号: 9725361
• 负责人: Marcus Bursik
• 金额: $ 18.64万
• 依托单位: CUBRC, INC.
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-02-01 至 2002-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9725361&HistoricalAwards=false
• 关键词: Topographic; Controls; Generation; Elutriated; Ash

9725361 Bursik Pyroclastic flows or nuees ardentes are perhaps the most destructive, yet most poorly understood of volcanic phenomena. Because of their destructiveness, they are virtually impossible to observe directly; yet they leave deposits that have proven extremely difficult to interpret. The primary objective of the proposed research is to determine in specific, well-constrained situations the link between active flow conditions in pyroclastic flows and the resulting deposits. Because we may be able to determine what is happening within the flows, the results could have important ramifications for the simulation of flows in hazards analysis, and for volcanic hazards assessment. The proposed work will procede with experimental, theoretical and fieldwork phases. The work will begin by carefully making deposits in the laboratory under well-constrained flow conditions, using special facilities designed only for the purpose of these studies. Theoretical modeling will extend the range of applicability of the experiments by generalizing the observed flow mechanics. Laboratory and theoretical results will be tested by careful sedimentological analysis of certain diagnostic portions of pyroclastic flow deposits, especially modern deposits for which there is some information on active flow conditions.

9725361 bursik pyroclastic Flow或Nuees Ardentes可能是对火山现象的最具破坏性，但最知名的。 由于它们的破坏性，它们几乎不可能直接观察。然而，他们留下了被证明很难解释的存款。 拟议研究的主要目标是在特定的，受良好约束的情况下确定火山碎屑流中的主动流条件与所得沉积物之间的联系。 因为我们可能能够确定流量内发生的情况，因此结果可能会在危害分析和火山危害评估中对流量进行模拟有重要的影响。 拟议的工作将使用实验，理论和现场工作阶段进行。 这项工作将首先使用仅用于这些研究目的的特殊设施在受良好的流动条件下仔细地存入实验室的沉积物。 理论建模将通过概括观察到的流动力学来扩展实验的适用性范围。 实验室和理论结果将通过对某些诊断部分的诊断部分的沉积学分析来测试，尤其是现代沉积物，其中有一些有关活动流动条件的信息。