Topographic Controls on the Generation of Elutriated Ash Clouds

9316656 Bursik 要测试的主要假设是淘析火山灰云（其中“coignimbrite”火山灰云是其中的一个子集）的生成方式在很大程度上取决于火山碎屑流和火山涌与火山周围地形的相互作用。 因此，我们的目标是了解灰云生成机制以及流动和喘振机制，特别是当它们受地形影响时。 拟议的研究将包括详细的沉积学测量、实验室实验和理论建模。 现场工作将包括一种新颖的采样策略，该策略应用于墨西哥埃尔奇雄火山 1982 年的沉积物，采样点位于平行流向的横断线上，间隔很近。 采样策略将产生可用于测试流动行为理论模型的定量数据。 实验室实验将与现场数据分析和理论模型的开发结合起来，为现场数据的解释和验证理论提供约束。 拟议的活动将加深人们对火山碎屑流和涌流淘洗火山灰云的机制的了解。

9316656 Bursik The primary hypothesis to be tested is that the manner in which elutriated ash clouds (of which 'coignimbrite' ash clouds are a subset) are generated is strongly dependent upon the interaction of pyroclastic flows and surges with the topography surrounding a volcano. Our objectives are therefore to understand ash cloud generating mechanisms and flow and surge mechanisms especially as they are affected by topography. The proposed research will consist of detailed sedimentological measurements, laboratory experiments and theoretical modeling. Field work will consist of a novel sampling strategy applied to the 1982 deposits of El Chichon volcano, Mexico, at closely spaced sites lying along traverse that traverse that parrallel flow directions. The sampling strategy will yield quantitative data that can be used to test theoretical models of flow behavior. Laboratory experiments will be conducted in conjunction with the analysis of the field data and the development of theoretical models to provide constraints on interpretations of field data and validation theory. The proposed activity will yield increased understanding of the mechanisms through which ash clouds are elutriated from pyroclastic flows and surges.