NSFGEO-NERC: Linking geophysics and volcanic gas measurements to constrain the transcrustal magmatic system at the Altiplano-Puna deformation anomaly

NSFGEO-NERC：将地球物理学和火山气体测量联系起来，以约束高原-普纳变形异常处的跨地壳岩浆系统

基本信息

批准号：
NE/S008845/1
负责人：
Joachim Gottsmann
金额：
$ 31.13万
依托单位：
University of Bristol
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%2FS008845%2F1
关键词：
NSFGEO NERC Linking geophysics volcanic

项目摘要

The path that magma takes through the crust is not well understood -- where is magma stored and under what conditions will it erupt? While this question is of fundamental scientific interest, it is also directly related to understanding the hazard posed by volcanic systems that are showing signs of activity and unrest. This proposal seeks to understand the cause of unrest and the architecture of the magma storage system within the central Andes, home to the world's largest geophysically imaged zone of silicic partial melt, the Altiplano-Puna Magma (or Mush) Body (APMB).The new paradigm of a transcrustal magmatic system (TCMS) where magma is stored and undergoes chemical changes occurs at several locations throughout the entire crust. This conceptual revolution is being driven by petrological, geochronological, and geochemical studies of magma storage conditions that show (1) many large eruptions tap multiple melt sources, (2) large melt bodies are probably transient features, (3) crystals carried by the transporting melt have been stored at a range of pressures and temperatures. A key location to assess and refine models of currently active TCMS is at the APMB, where a large ground deformation pattern 150 km in diameter lasting several decades has been observed centered on Uturuncu volcano, Bolivia. By collecting and analyzing new interdisciplinary field measurements (gravity, ground deformation, seismic, gas flux and composition) and developing 3D numerical models, this proposal will answer several outstanding questions about the nature of TCMS at the APMB: 1. What is the cause of deformation in the midcrust at the APMB: a magmatic diapir, cyclic up and down movements from magma mush reorganization involving magma and/or volatiles, or something else? 2. What is the nature of a shallow-seated conductivity anomaly -- to what extent is it partial melt, a hydrothermal brine reservoir, or a mature ore body? 3. What is the flux of volatiles through the TCMS? 4. How important is crustal anisotropy in the interpretation of the subsurface magma plumbing architecture?We propose a multi-parametric study to test specific aspects of the TCMS in the central Andes that could be broadly applicable to other TCMS currently active in the world and in the geologic record. Using a closely coordinated international geophysical and geochemical approach with funding from both the US NSF and UK NERC, we will test and refine the possible cause of the ground deformation, better constrain the shallow structure, determine whether deformation is still occurring, and make the first measurements of the volatile flux through the system.

岩浆穿过地壳的路径尚不清楚——岩浆储存在哪里以及在什么条件下会喷发？虽然这个问题具有基本的科学意义，但它也与了解显示出活动和不稳定迹象的火山系统所造成的危险直接相关。该提案旨在了解动乱的原因以及安第斯山脉中部岩浆储存系统的结构，安第斯山脉中部是世界上最大的硅质部分熔融地球物理成像区——高原-普纳岩浆体（APMB）的所在地。跨地壳岩浆系统（TCMS）的新范例，岩浆在整个地壳的多个位置储存并经历化学变化。这一概念革命是由岩浆储存条件的岩石学、地质年代学和地球化学研究推动的，这些研究表明（1）许多大型喷发利用多个熔体源，（2）大型熔体可能是瞬态特征，（3）运输过程中携带的晶体熔体已在一定压力和温度下储存。评估和完善当前活跃的 TCMS 模型的关键地点是 APMB，在那里观察到以玻利维亚乌图伦库火山为中心的直径 150 公里的大地面变形模式持续了几十年。通过收集和分析新的跨学科现场测量（重力、地面变形、地震、气体通量和成分）并开发 3D 数值模型，该提案将回答有关 APMB 的 TCMS 性质的几个突出问题： 1. 造成这种现象的原因是什么？ APMB 中地壳的变形：岩浆底辟、涉及岩浆和/或挥发物的岩浆糊状物重组引起的周期性上下运动，还是其他什么？ 2. 浅层电导率异常的本质是什么——在多大程度上是部分熔融、热液储层还是成熟矿体？ 3. 通过 TCMS 的挥发物通量是多少？ 4. 地壳各向异性在解释地下岩浆管道结构中有多重要？我们提出了一项多参数研究来测试安第斯山脉中部 TCMS 的特定方面，该研究可以广泛适用于目前在世界和其他地区活跃的其他 TCMS地质记录。在美国 NSF 和英国 NERC 的资助下，我们将采用密切协调的国际地球物理和地球化学方法，测试和细化地面变形的可能原因，更好地约束浅层结构，确定变形是否仍在发生，并做出第一个测量通过系统的挥发性通量。

项目成果

期刊论文数量（10）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Rheological Controls on Magma Reservoir Failure in a Thermo-Viscoelastic Crust

热粘弹性地壳中岩浆库破坏的流变控制

DOI：
10.1029/2021jb023439
发表时间：
2022
期刊：
Solid Earth
影响因子：
3.4
作者：
Head M
通讯作者：
Head M

The Influence of Viscoelastic Crustal Rheologies on Volcanic Ground Deformation: Insights From Models of Pressure and Volume Change

粘弹性地壳流变对火山地面变形的影响：来自压力和体积变化模型的见解

DOI：
10.1029/2019jb017832
发表时间：
2019
期刊：
Solid Earth
影响因子：
3.4
作者：
Head M
通讯作者：
Head M

Exploring the Impact of Thermally Controlled Crustal Viscosity on Volcanic Ground Deformation

探索热控地壳粘度对火山地面变形的影响

DOI：
10.1029/2020jb020724
发表时间：
2021
期刊：
Solid Earth
影响因子：
3.4
作者：
Head M
通讯作者：
Head M

Hydrothermal Fluids and Where to Find Them: Using Seismic Attenuation and Anisotropy to Map Fluids Beneath Uturuncu Volcano, Bolivia

热液以及在哪里可以找到它们：利用地震衰减和各向异性来绘制玻利维亚乌图伦库火山下方的流体图

DOI：
10.1029/2022gl100974
发表时间：
2023
期刊：
Geophysical Research Letters
影响因子：
5.2
作者：
Hudson, T. S.;Kendall, J. M.;Blundy, J. D.;Pritchard, M. E.;MacQueen, P.;Wei, S. S.;Gottsmann, J. H.;Lapins, S.
通讯作者：
Lapins, S.

From slab to surface: Earthquake evidence for fluid migration at Uturuncu volcano, Bolivia

从板块到地表：玻利维亚乌图伦库火山流体迁移的地震证据

DOI：
10.1016/j.epsl.2021.117268
发表时间：
2022
期刊：
Earth and Planetary Science Letters
影响因子：
5.3
作者：
Hudson, Thomas S.;Kendall, J-Michael;Pritchard, Matthew E.;Blundy, Jonathan D.;Gottsmann, Joachim H.
通讯作者：
Gottsmann, Joachim H.