Abstract Estimates of the rheological properties of lava flows are essential for understanding their emplacement and for hazard assessment. Despite being a well-known phenomenon in water hydraulics, the formation and presence of standing waves in lava channels is poorly understood. Standing waves, generally located near the vent area, have been frequently described at high speed channelized lava flows. They are interpreted as hydraulic jumps indicating a flow under supercritical conditions. Identifying standing waves therefore offers an opportunity to apply open channel hydraulic theory for supercritical flows in order to determine important eruption parameters such as discharge rate and apparent viscosity. We use the length and amplitude of standing waves to reconstruct flow dynamics from both observational data and video analysis. The geometry of these standing waves allows us to extract the physical properties of the channelized lava (velocity, discharge rate, apparent viscosity), to estimate the channel depth and constrain the flow regime. With the rapid advances in technology, scientists can deploy equipment to enable low-cost real time monitoring of these phenomena and constrain eruption discharge rate and apparent viscosity, key parameters for volcanic hazard assessment and mitigation.

中文翻译：

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高速熔岩通道中的驻波：限制熔岩动力学和喷发参数的工具

摘要 熔岩流流变特性的估计对于了解熔岩流的位置和危险评估至关重要。尽管是水力学中众所周知的现象，但对熔岩通道中驻波的形成和存在知之甚少。驻波通常位于喷口区域附近，经常被描述为高速通道化熔岩流。它们被解释为表明超临界条件下流动的水跃。因此，识别驻波提供了将明渠水力理论应用于超临界流动的机会，以确定重要的喷发参数，例如排放率和表观粘度。我们使用驻波的长度和幅度从观测数据和视频分析中重建流动动力学。这些驻波的几何形状使我们能够提取通道化熔岩的物理特性（速度、排放速率、表观粘度），以估计通道深度并限制流动状态。随着技术的快速进步，科学家们可以部署设备以低成本实时监测这些现象，并限制喷发排放率和表观粘度，这是火山灾害评估和缓解的关键参数。