RUI: Dynamics of Plinian Eruptions - Physical Volcanology of the 1600 Eruption of Volcan Huaynaputina, Southern Peru

RUI：普林尼式喷发的动力学 - 1600 年秘鲁南部 Huaynaputina 火山喷发的物理火山学

• 批准号: 0087181
• 负责人: Shanaka de Silva
• 金额: $ 15.38万
• 依托单位: Indiana State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-01-15 至 2002-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0087181&HistoricalAwards=false
• 关键词: RUI; Dynamics; Plinian; Eruptions; Physical

0087181DeSilvaIn attempting to better understand the human, societal, and environmental impacts of volcanic eruptions, scientists are increasingly aware that the fundamental underpinning to this endeavour is knowledge about the physical volcanology of volcanic eruptions. Since plinian eruptions are amongst the most devastating, considerable effort is focused on these phenomena. However, few such eruptions have been observed and documented and our understanding relies heavily on data from eruptions that have occurred in the recent past. Such studies have proved to be the source of much of our insight into the dynamics of plinian eruptions and their local and global effects. A completed study of the 1600 eruption of Huaynaputina, conducted under the auspices of a previous NSF grant, reveals that this eruption is one of the most significant eruptions of historic times. Over 25km3 of tephra was erupted, 90% of which was ejected during a ~20 hour sustained plinian eruption during the first stage of the eruption. Two coeval but distinct deposits formed; a regionally extensive and well-preserved plinian pumice fall deposit, and a much more extensive plinian ash deposit. No caldera collapse occurred despite the large volume erupted allowing the rare preservation of ultraproximal sections and vents. This project will build on the general model of the eruption that we have elucidated to focus on the ultraproximal sections and the proximal pumice fall deposit to increase our understanding of the 1600 Stage I plinian eruption in particular and the dynamics of plinian eruptions in general. Two interrelated objectives are to be addressed. The first is better constrain the evolution of the ~20 hour long plinian eruption, and the second is to better understand the origin and significance of the extremely coarse fall deposits in the ultraproximal sections. These objectives will be addressed through extensive fieldwork to log sections, identify and map key horizons, and map their dispersal. These data will be coupled with existing detailed grainsize and componentry of these horizons throughout the fall deposit to develop a more detailed understanding of the Stage I plinian eruption that breaks down the ~20 hour eruption into several stages. The involvement of graduate and undergraduate students as key players in the team maximises the educational impact of this project.

0087181DeSilva 在试图更好地了解火山喷发对人类、社会和环境的影响时，科学家们越来越意识到，这一努力的根本基础是有关火山喷发的物理火山学的知识。由于普林尼式喷发是最具破坏性的喷发之一，因此人们对这些现象投入了大量的精力。然而，很少有这样的喷发被观察到和记录，我们的理解在很大程度上依赖于最近发生的喷发的数据。事实证明，此类研究是我们深入了解普林尼式喷发动态及其局部和全球影响的根源。在美国国家科学基金会之前的资助下，对 1600 年华纳普蒂纳火山喷发进行的完整研究表明，这次喷发是历史上最严重的喷发之一。超过 25 平方公里的火山灰喷发，其中 90% 在喷发第一阶段持续约 20 小时的普林尼式喷发中喷出。形成了两个同时代但不同的矿床；区域广泛且保存完好的普林尼浮石沉积物，以及更广泛的普林尼灰沉积物。尽管喷发量较大，但并未发生破火山口塌陷，从而使得极近端部分和喷口得以罕见保存。该项目将建立在我们已经阐明的喷发一般模型的基础上，重点关注超近端部分和近端浮石沉积物，以增加我们对 1600 年第一阶段普林尼式喷发的了解，特别是普林尼式喷发的动力学。有两个相互关联的目标需要解决。第一个是更好地限制约20小时长的普林尼式喷发的演化，第二个是更好地理解超近端部分极其粗大的坠落沉积物的起源和意义。这些目标将通过广泛的实地工作来实现，以记录剖面、识别和绘制关键视野，并绘制其分布图。这些数据将与整个秋季沉积物中现有的详细颗粒尺寸和这些层位的组成相结合，以更详细地了解第一阶段普林尼式喷发，将大约 20 小时的喷发分为几个阶段。研究生和本科生作为团队关键成员的参与最大限度地提高了该项目的教育影响。