Collaborative research: magma reservoir-conduit dynamics as revealed by a borehole geophysical observatory and continuous GPS

[01:16485 . jansma]蒙特塞拉特岛上正在喷发的Soufriere Hills火山（SHV）为研究安山岩火山的复杂岩浆过程提供了前所未有的机会。熔岩穹丘的生长是不稳定的，并伴随着地面变形、地震活动和爆炸性喷发的循环模式。周期包括短期尺度（6-18小时）、中期尺度（~7周）和长期尺度（~30年）。它们提供了对安山岩火山喷发动力学的见解，短期周期表明，脱气、岩浆的流变硬化和上部管道的加压是耦合的，并控制着许多观测到的地球物理和动力学现象。中、长期旋回可能反映了涉及岩浆储层的深层作用。该项目将在SHV周围的四个200米井眼和几个较浅的井眼中使用集成的专业仪器阵列来研究整个系统的动力学。该系统是积极和动态的，并将在可预见的未来保持这种状态。对这些仪器提供的连续易腐数据的分析将为涉及安山岩岩浆系统动态行为的理论模型提供重要的新见解和具体约束。这是一个合作项目，涉及宾夕法尼亚州立大学、华盛顿卡内基研究所、阿肯色大学的私家侦探、蒙特塞拉特火山天文台（MVO）以及英国布里斯托尔大学和利兹大学的科学家。英国调查人员已获得资助，以分担钻探成本并支持英国的科学分析。MVO的专业知识、设施和数据库也提供分摊费用的贡献

0116485Jansma The ongoing eruption of the Soufriere Hills Volcano (SHV) on Montserrat provides an unprecedented opportunity to investigate complex magmatic processes at an andesitic volcano. Growth of the lava dome has been unsteady and accompanied by cyclic patterns of ground deformation, seismicity, and explosive eruptions. The cycles include a short-term scale (6-18 hour), a meso-term scale (~7 weeks), and a long-term scale (~30 y). They provide insights into eruption dynamics at andesite volcanoes, with the short-term cycles suggesting that degassing, rheological stiffening of the magma, and pressurization in the upper conduits are coupled and control many of the geophysical and dynamical phenomena observed. The meso- and long- term cycles may reflect deep-seated processes involving the magma reservoir. This project will investigate the dynamics of the full system using an integrated array of specialized instruments in four strategically located 200-m boreholes, and several shallower holes, surrounding SHV. The system is active and dynamic and will remain so for the foreseeable future. Analysis of the continuous perishable data provided by these instruments should provide important new insights and specific constraints to theoretical models, involving the dynamic behavior of the andesite magmatic system.This is a collaborative project involving P.I.s from Penn State University, Carnegie Institution of Washinton, University of Arkansas, in collaboration with Montserrat Volcano Obervatory (MVO) and scientists from Bristol and Leeds Universities in the UK. The UK investigators have been funded to share drilling costs and to support UK scientific analyses. The expertise, facilities, and database of MVO also provide cost-share contributions.***