Solidification Fronts in Sill-Like Magma Chambers

无论大小，凝固锋从岩床、熔岩和熔岩湖的上缘和下缘向内扩散，并在很大程度上控制着岩浆的演化。这些锋面或结壳的特点是结晶度和粘度发生强烈变化。它们将岩浆过程划分为两个区域：(1)主要由流体过程(例如，晶体沉淀和对流)主导的向内区域，以及(2)在凝固前锋本身内，主要由晶间过程(例如，多孔流动和压实)主导的外部区域。这项建议的目的是调查这些区域之间的动态相互作用，并了解每个区域所特有的物理和化学过程。拟议的调查既涉及实地工作，也涉及理论工作。它将提高我们对相对较薄的岩浆体是如何凝固的理解，并允许对这一过程进行建模。

Solidification fronts propagate inward from the upper and lower margins of sills, lavas, and lava lakes, regardless of size, and largely control magmatic evolution. These fronts or crusts are characterized by strong changes in crystallinity and viscosity. They partition magmatic processes into two regions: (1) an inward region dominated largely by fluid processes (e.g., crystal settling and convection), and (2) an outer region, within the solidification fronts themselves, dominated largely by intercrystalline processes (e.g., porous flow and compaction). The aim of this proposal is to investigate the dynamic interplay between these regions and to understand the physical and chemical processes that characterize each region. The proposed investigation involves both field and theoretical work. It will improve our understanding of how relatively thin magma bodies solidify and permit modeling of that process.