Complex Episodic Explosive Volcanism: Eruption Dynamics of the 1959 Kilauea Iki Eruption, Hawaii

1959年的基拉韦厄火山喷发是有记录以来最有记录的玄武岩喷发之一。在这次喷发期间，观察到了该火山有记录以来最高的熔岩喷泉，在37天内发生了16个阶段的爆炸活动。然而，这些喷火事件的长度和间距是不规律的，并伴随着熔岩从邻近的基拉韦厄Iki陨石坑新形成的熔岩湖中排出和排入。理解这一经典喷发的一个新的合乎逻辑的步骤是进入喷发内部，将单个喷发阶段或事件视为离散的实体。该项目的主要目标是完成对这一复杂的火源喷发的火山碎屑产物的记录，确定喷发间歇性的根本原因，以及喷发产物中网状浮石和渣油飞溅的对比丰富和扩散情况。研究人员计划首先完善观察到的锥体生长速度和性质的数据库，以与喷泉高度随时间变化的记录相匹配。其次，他们将绘制广泛分布的珊瑚-浮石岩层中的各个床层，并将它们分配到个别喷发时期，并限制它们的扩散。最后，他们将量化喷发碎屑中气泡和微晶石群的大小分布，以限制攀升、喷发和冷却的对比历史。就更广泛的影响而言，更清楚地了解夏威夷玄武岩喷发的触发机制对于评估未来玄武岩火山爆发事件的危险并增进对这些火山行为范围的了解至关重要。更具体地说，2002年夏威夷火山国家公园(HVNP)的230万游客中，几乎所有人都参观了基拉韦厄火山1959年的矿藏。它计划与HVNP建立合作伙伴关系，利用独立资金开发一系列产品和解释活动，使这次喷发成为游客的展示窗口。这次喷发已经成为研究生四个实地讲习班的基础，并成为活火山研究中心开办的年度课程的专题。结果将通过由夏威夷火山国家公园、夏威夷火山观测站和夏威夷大学主办的链接网站通过互联网广泛传播。

The 1959 eruption of Kilauea Iki was one of the best-documented basaltic explosive eruptions ever recorded. The highest lava fountains yet recorded for that volcano were observed during this eruption and 16 phases of explosive activity took place over 37 days. However, these fire-fountaining episodes were of irregular length and spacing and accompanied by drainage of lava from and into a newly formed lava lake in the adjacent Kilauea Iki crater. A new logical step in understanding this classical eruption is to move inside the eruption to treat individual eruptive phases or episodes as discrete entities. The primary goal of this project is to complete the documentation of the pyroclastic products of this complex fire-fountaining eruption identifying underlying causes of the episodic nature of the eruption, and the contrasting abundance and dispersal of reticulite-pumice and scoria-spatter in the eruption products. The investigators plan to first refine the database of observations of the rates and nature of cone growth to match to the record of fountain height with time. Secondly, they will map individual beds in the widespread scoria-pumice blanket and assign them to individual eruptive episodes and constrain their dispersal. Finally they will quantify size distributions of bubble and microlite populations in the erupted clasts to constrain contrasting histories of ascent, eruption, and cooling. In terms of broader impacts, a clearer understanding of the triggering mechanisms of Hawaiian basaltic eruptions is of fundamental importance in order to assess hazards of future explosive events at basaltic volcanoes, and to improve understanding of the range of behaviors of these volcanoes. More specifically, the Kilauea Iki 1959 deposits are visited by almost all of the 2.3 million visitors to Hawaii Volcanoes National Park (HVNP) in 2002. It is planned to form a partnership with HVNP using independent funding to develop a range of products and interpretative activities to make this eruption a showcase for visitors. The eruption has already formed the basis for four field workshops for graduate students and features in the annual courses run by the Center for the Study of Active Volcanoes. The results will be widely disseminated via the Internet using linked web sites hosted by Hawaii Volcanoes National Park, Hawaiian Volcano Observatory and University of Hawaii.