| 项目编号: | 1551808
|
| 项目名称: | Investigating the relationships among subduction character, volatile cycling, and eruptive activity along the Aleutian Arc |
| 作者: | Tobias Fischer
|
| 承担单位: | University of New Mexico
|
| 批准年: | 2016
|
| 开始日期: | 2016-06-01
|
| 结束日期: | 2018-05-31
|
| 资助金额: | 57978
|
| 资助来源: | US-NSF
|
| 项目类别: | Standard Grant
|
| 国家: | US
|
| 语种: | 英语
|
| 特色学科分类: | Geosciences - Earth Sciences
|
| 英文关键词: | volatile
; aleutian arc
; volcanic activity
; arc
; aleutian volcanic arc
; magma
; western aleutian volcano
; eruptive activity
; central aleutian volcano
; volatile cycling
; subduction character
; western aleutian
|
| 英文摘要: | The Aleutian Volcanic Arc stretches about 4,000 km from mainland Alaska to Kamchatka, Russia, separating the Bearing Sea to the north and the Pacific Ocean to the south. The arc is home to about 145 volcanoes of which 52 have erupted in historic time. The eruptive activity of these volcanoes ranges from continuous small explosions to devastatingly large eruptions such as the one that occurred at Katmai in 1912. Volcanic activity in the Aleutian Arc is a result of subduction of the Pacific plate beneath the North American plate. During this process, volatile elements such as water, carbon and nitrogen that are locked up in the sediments and oceanic crust are slowly transferred into the region deep under the Aleutian Arc volcanoes. Under high pressure the volatiles are squeezed out of the subducting plate into the overlying (mantle) region, where they help to melt rock and generate magma. The lower density of the magma and volatiles compared to the surrounding rock allows these fluids to ascend to the Earth's surface where the magma ultimately erupts through volcanism and the gases are released to the atmosphere. While it is well-known that volatiles play a significant role in both generating magma and influencing eruption explosivity, it is currently not well understood how the source of volatiles (subducted plate, mantle and crust) and the amount of volatiles released over time (e.g. their flux), may influence volcanic eruption size, explosivity and frequency. This project aims to constrain the process of volatile subduction and release through volcanism in the poorly studied Western Aleutians, and to provide insight into volcanic activity.
The Western and Central portions of the Aleutian Volcanic Arc are the ideal locations to investigate the influence of subduction angle, rate and sediment composition on magma generation and volatile flux. The subduction rate and sediment flux increases along the arc from Kiska, the western-most volcano, to Cleveland, located within the central region of the arc. Additionally, the number of historic eruptions within Central Aleutian volcanoes appears to be greater in number than compared to the Western Aleutian volcanoes. Through a previous expedition volcanic gas samples, gas emission measurements and explosively erupted lava samples were collected at five Western Aleutian volcanoes. Through this project these samples will be analyzed for their chemical and isotopic composition and measurements will be used to compute the fluxes of carbon dioxide, sulfur dioxide, nitrogen and water to the atmosphere. Constraints on the quantity and type of material subducted into the Aleutian Arc from previous studies will be compared to the composition of volatile and lava outputs, as well as the total flux of volatiles measured here, to provide insight into volatile cycling and magma generation. This information will be compared to historic data on eruption size, style and frequency for each of the target volcanoes to identify possible links between subduction character and volcanic activity, to ultimately help improve eruption forecasting and hazard mitigation. |
| 资源类型: | 项目
|
| 标识符: | http://119.78.100.158/handle/2HF3EXSE/92277
|
| Appears in Collections: | 全球变化的国际研究计划
科学计划与规划
|
|
There are no files associated with this item.
|
| Recommended Citation: | |
Tobias Fischer. Investigating the relationships among subduction character, volatile cycling, and eruptive activity along the Aleutian Arc. 2016-01-01.
|
|
|