The Strombolian Conduit: What Happens in the Last 250 m?

Strombolian 导管：最后 250 m 会发生什么？

• 批准号: 0738106
• 负责人: Andrew J. Harris
• 金额: $ 24.95万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-06-15 至 2012-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0738106&HistoricalAwards=false
• 关键词: Strombolian; Conduit; What; Happens; Last

The type of volcanic explosive activity known as Strombolian is characterized by repeated, low energy, explosions and is named after the volcano where such activity has persisted for around 2000 years, i.e., Stromboli in the Aeolian Islands (Italy). Because activity is guaranteed, Stromboli represents an excellent laboratory where measurements of the explosions can be made from safe, but close, distances. This allows us to understand what causes the volcanic explosion and then how the erupted cloud of bombs, ash and gas moves. Measuring these properties alone would be an advance itself, but it will also allow us to further understand how and why a volcano erupts and how its potentially hazardous explosive products are dispersed. This project will be coordinated with other scientists from the University of Florence and in collaboration with the Italian agencies responsible for monitoring this volcano. It is expected that the results can feed back to help improve the understanding of the explosive behavior of US volcanoes, where a new vent opening on Kilauea that required the shut-down of a section of the Hawaii Volcanoes National Park, is degassing in a very similar manner to Stromboli's open vents. The team will also directly feed results from this research into the education and training of our University of Hawaii students who will work with, and learn from, the collected data.To achieve our aims it is planned to combine a number of new technologies, such as hand-held thermal infrared cameras. These allow us to take thermal images of the plume at frame rates of up to 40 frames per second as it ascends from the vent. In addition, they will use a new, portable, generation of sulfur dioxide gas sensors that enables tracking of the variation in gas emission during each explosion. Simple numbers such as the velocity, volume and density of the explosion cloud are extremely hard to measure but are pivotal in predicting how a cloud will rise and drift. These new technologies will provide essential data regarding these key properties. Another key piece of evidence in determining what causes the explosions is locked in the scoriae that are thrown out during the explosion. Their textures (in terms of bubbles and crystals) contain precious information about the conduit dynamics that led to the explosion. At the same time the explosion produces a sound, as well as earth tremor, that also tells us about the source properties of the explosion. Thus, it is also planned to sample these scoriae, and combine their information with sonic, seismic, thermal and gas sensor data to understand how the explosion is generated, how the cloud ascends the conduit and, then, how it exits the vent.

被称为斯特龙博利火山的火山爆炸活动的特点是反复、低能量的爆炸，并以这种活动持续了大约2000年的火山命名，即意大利埃奥利亚群岛的斯特龙博利火山。由于活动是有保证的，斯特龙博利代表了一个优秀的实验室，在这里可以从安全但近距离测量爆炸。这使我们能够了解是什么导致了火山爆炸，然后喷发出的炸弹、火山灰和气体云是如何移动的。仅测量这些特性本身就是一种进步，但它也将使我们能够进一步了解火山喷发的方式和原因，以及其潜在危险的爆炸产品是如何分散的。该项目将与佛罗伦萨大学的其他科学家协调，并与负责监测这座火山的意大利机构合作。预计结果可以反馈到有助于提高对美国火山爆炸行为的了解，基拉韦厄火山上的一个新喷口需要关闭夏威夷火山国家公园的一段，正在以非常类似于斯特龙博利打开的喷口的方式进行除气。该团队还将把这项研究的结果直接输入到夏威夷大学学生的教育和培训中，他们将利用收集的数据进行合作和学习。为了实现我们的目标，计划结合一些新技术，如手持热红外相机。这使我们能够在羽流从喷口上升时以高达每秒40帧的帧速率拍摄热像。此外，他们将使用新一代便携式二氧化硫气体传感器，能够跟踪每次爆炸期间气体排放的变化。简单的数字，如爆炸云的速度、体积和密度，极难测量，但在预测云如何上升和漂移方面至关重要。这些新技术将提供有关这些关键特性的基本数据。确定爆炸原因的另一个关键证据是锁定在爆炸过程中抛出的蝎子中。它们的纹理(就气泡和晶体而言)包含了有关导致爆炸的管道动力学的宝贵信息。与此同时，爆炸产生的声音和地震一样，也告诉我们爆炸的震源特性。因此，还计划对这些蝎子进行采样，并将它们的信息与声波、地震、温度和气体传感器数据结合起来，以了解爆炸是如何产生的，云是如何沿着管道上升的，然后是如何离开喷口的。