Collaborative Research: Chamber or Conduit - Constraining Explosive Through Effusive Eruption at Cordon Caulle, Chile 2011/12

火山爆发是构造活动大陆边缘的主要危险之一，例如美国西北太平洋地区，对不断扩大的人口具有日益增长的经济和生存重要性。该项目将增进对导致富含二氧化硅的岩浆喷发的条件的了解，这些岩浆可能是巨大的和有影响力的。实现这一目标取决于通过可靠的物理模型整合观测结果，这些模型的预测能力已经过测试。这是该项目的主要重点，它将促进对决定火山爆发从开始到停止的进展的基本过程的了解，火山爆发仍然难以预测。因此，该项目超越了纯学术性，通过提高自然灾害评估能力而具有社会相关性。此外，该项目还通过对研究生、本科生和博士后学者进行跨学科培训，支持教育，从而为培养具有全球竞争力的多样化劳动力做出贡献。该项目的目标是通过模拟火山喷发从最初的爆炸活动到熔岩溢出，以2011/12年智利Cordon Caulle火山爆发为例，研究了火山爆发后的通货膨胀与火山喷发终止之间的关系。对于这次喷发的助跑，同喷发的演变，和火山系统的喷发后重新配置记录在前所未有的细节。喷发最初是爆炸性的，随着时间的推移，喷发率下降，活动从纯粹的爆炸性转变为喷涌性，导致形成大的熔岩流和浅的岩盖。目前关于这些类型的喷发的观点是，在一定范围的相同条件下，可能发生喷涌或爆炸活动，并可能从一种快速过渡到另一种。该项目的一个目标是评估导致喷发活动转变的条件，以检验这种爆炸-喷出双稳性假设。此外，快速爆发后的通货膨胀被观察到，进一步的目标是评估系统已被驱回临界状态的程度。这些目标将通过在广泛的基于物理的模型模拟中整合不同的观测数据来实现，这将导致模型可靠性的提高，并进一步了解Cordon Caulle和其他地方类似的危险火山系统的基本过程。该项目本身是多学科的，包括地球化学、岩石学和大地测量学，以及岩浆储存和喷发的数值模拟。因此，该项目也是多机构的，除了现有的观测之外，还将通过其他合作机构牵头的努力获得新的数据。莱斯大学将与其他机构合作，重点关注该项目的数值模拟和不同类型观测数据的整合。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Volcanic eruptions pose one of the principal hazards at tectonically active continental margins, such as the Pacific northwestern United States, which are of ever increasing economic and existential importance to expanding populations. The project will enhance knowledge of the conditions that lead to eruptions of silica-rich magmas, which can be large and impactful. Achieving this goal is contingent upon the integration of observations through reliable physics-based models that have been tested in their predictive capabilities. This is the project's principal focus and it will advance understanding of the fundamental processes that determine the progression of volcanic eruptions, from inception to cessation, which remains difficult to forecast. Consequently, the project transcends the purely academic and is societally relevant by advancing natural hazard assessment capabilities. Furthermore, the project supports education by enabling the interdisciplinary training of graduate and undergraduate students as well as a postdoctoral scholar, thus contributing to the development of a diverse and globally competitive workforce.The project's objective is to advance fundamental knowledge of how volcanoes work by simulating a volcanic eruption from initial explosive activity through lava effusion, to termination of the eruption and post-eruptive inflation, using the 2011/12 Cordon Caulle eruption in Chile as a case study. For this eruption the run-up, the syn-eruptive evolution, and the post-eruptive reconfiguration of the volcanic system were documented in unprecedented detail. The eruption was initially explosive and over time eruption rates decreased with activity shifting from purely explosive to effusive, resulting in the formation of a large lava flow and shallow laccolith. The current view about these types of eruptions is that over some range of identical conditions effusive or explosive activity is possible and with potentially rapid transitions from one to the other. One goal of the project is the assessment of conditions resulting in transitions in eruptive activity in order to test this explosive-effusive bistability hypothesis. Moreover, rapid post-eruptive inflation was observed and a further goal is to assess the extent to which the system has been driven back toward a critical state. These goals will be achieved by integrating the different observational data within extensive physics-based model simulations that will lead to improvements in model reliability and further our understanding of underlying processes at Cordon Caulle and similar hazardous volcanic systems elsewhere. The project as such is multi-disciplinary and encompasses geochemistry, petrology and geodesy, in addition to numerical simulation of magma storage and eruption. As a consequence, the project is also multi-institutional and in addition to existing observations, new data will be acquired through efforts led by the other collaborating institutions. The portion of the project that Rice University will focus on - in collaboration with the other institutions - are the numerical simulation and the integration of the different types of observational data.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.