Shear-wave splitting Tomography At Kilauea

基拉韦厄剪切波分裂断层扫描

• 批准号: NE/S009043/1
• 负责人: Jessica Johnson
• 金额: $ 6.68万
• 依托单位: University of East Anglia
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FS009043%2F1
• 关键词: Shear; wave; splitting; Tomography; Kilauea

Kilauea volcano, in Hawaii, is one of the most active volcanoes in the world. Since 2008, there has been an eruptive vent at the summit of the volcano, with a lava lake. Further down the volcano, there has been another vent erupting lava since 1985. In April 2018, magma supply stopped at these two places, and travelled under the ground to the residential region of Puna, where it erupted in 24 different fissures. Over 2000 people have been evacuated from their homes and up to 700 buildings have been destroyed by lava flows. The last time there was an eruption in this area was 1960.When magma pushes its way through the rock, it causes lots of small earthquakes. Earthquake waves can be polarised in a similar way to the way light is polarised. Rock polarises earthquake waves when it is under pressure and tiny cracks line up in one direction. This causes earthquake waves to travel faster in one direction (along the cracks) than the other (across the cracks). Therefore, we can use the polarisation of the earthquake waves to understand how the rock gets pressurised as the magma travels through it.This new eruptive activity at Kilauea means that we can investigate areas that we previously couldn't because there were not enough earthquakes. We will set up four new stations to measure the new earthquakes and use data from the existing monitoring network. We will use the new earthquakes to make images of the pressure in the rocks during this eruption and will be able to see what happens to the pressure when the eruption stops. This information will be useful to understand the eruptive behaviour of Kilauea, will help monitoring and forecasting changes in eruptive activity, and will also be applied to other volcanic systems around the world. To do this, we have made a team of excellent researchers from the University of East Anglia and the US Geological Survey.

位于夏威夷的基拉韦厄火山是世界上最活跃的火山之一。自2008年以来，火山顶部一直有一个喷发口，并有一个熔岩湖。在火山深处，自1985年以来一直有另一个火山口喷发熔岩。2018年4月，岩浆供应在这两个地方停止，并在地下移动到普纳的居民区，在那里爆发了24个不同的裂缝。超过2000人从家中撤离，多达700座建筑物被熔岩摧毁。这个地区上一次喷发是在1960年，当岩浆穿过岩石时，会引起许多小地震。地震波的偏振方式与光的偏振方式相似。岩石在压力下会极化地震波，微小的裂缝会朝一个方向排列。这导致地震波在一个方向（沿着裂缝）上的传播速度比在另一个方向（穿过裂缝）上的传播速度快。因此，我们可以利用地震波的偏振来了解岩浆在岩石中流动时岩石是如何被加压的。基拉韦厄的新喷发活动意味着我们可以调查以前因为地震不够而无法调查的地区。我们将建立四个新的监测站来测量新的地震，并使用现有监测网络的数据。我们将使用新的地震来制作火山爆发期间岩石中压力的图像，并将能够看到火山爆发停止时压力发生了什么变化。这些资料将有助于了解基拉韦厄火山的喷发行为，有助于监测和预测喷发活动的变化，并将应用于世界各地的其他火山系统。为此，我们组建了一支由东安格利亚大学和美国地质调查局的优秀研究人员组成的团队。

项目成果

Making the most of the Mogi model: Size matters

• DOI: 10.1016/j.jvolgeores.2021.107380
• 发表时间: 2021-11
• 期刊: Journal of Volcanology and Geothermal Research
• 影响因子: 2.9
• 作者: Nicola C. Taylor;Jessica H. Johnson;R. Herd

A Cautionary Tale of Topography and Tilt from Kilauea Caldera

基拉韦厄火山口地形和倾斜的警示故事

• DOI: 10.1029/2018gl081757
• 发表时间: 2019
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Johnson J