Tidally faced melting, magmatic segregation, and planetary evolution of Jupiter's moon Io. Theory and computational models

木卫一是木星的卫星，也是太阳系中火山活动最活跃的天体之一。这颗行星的内部动力还没有被很好地理解。这个项目的目的是发展和应用基于守恒原理的数学理论，使用复杂的数值模型获得解决方案，并基于结果，根据深度发生的动态过程解释对地球表面的观测。木卫一显示了强烈的火山活动，高温熔岩(1600-1700K)，以及平均表面热通量为2.5 W m-2(地球值的30倍)(见Schubert等人的评论)。2004年)。维持这种条件所需的热量供应据信来自木卫一、木卫二和木卫三之间的轨道共振引起的潮汐消散。这种潮汐加热被认为导致软流圈的部分融化，熔化的比例高达约20%。这些大的熔融分数比地球上认为的可能的要高，很可能是由于木卫一的低重力所允许的，从而阻止了压实作用的有效。许多问题都围绕着艾奥火山的地下关系。在低纬度，火山似乎均匀分布，最大限度地彼此分开(Hamilton等人，2013年)。这将意味着它们以某种方式在深处相互作用，但这种关系在高纬度地区没有观察到。计算机模型将体内的潮汐加热分布与熔体的形成和迁移联系起来，可以帮助探索这些有趣的观察结果。这将试图研究个别地物之下的熔融生产是否足以支持该地物的火山产出，如果不足以支撑，需要多大的集水区。这些模型还可以帮助回答围绕爱奥尼亚火山活动的其他谜团，例如低纬度火山活动的明显增加；山脉和火山地貌的局部相关性，但缺乏全球相关性；大型火山“爆发”的潜在时间聚集性；以及“自上而下的构造作用”的物理动力学。到目前为止，木卫一周围的工作通常没有将潮汐加热、熔体形成和熔体提取与完全热力学和两相流相结合。相反，它们简化了这些领域中的一个或多个，特别是倾向于简化两相流。这项工作将寻求将这些与最近的论文(特别是Bierson和Nimmo，2016)揭示的新的流变学考虑和潮汐加热分布计算结合在一起。该项目属于STFC职权范围内的“天文学和空间科学”研究领域。

Io is a satellite of Jupiter and among the most volcanically active bodies in the solar system. The internal dynamics of the planet are not yet well understood. The aim of this project is to develop and adapt mathematical theory based on conservation principles, obtain solutions using sophisticated numerical models, and based on the results, interpret surficial observations of the planet in terms of the dynamic processes happening at depth.Io shows intense volcanic activity, high-temperature lavas (1600-1700 K), and an average surface heat flux of 2.5 W m-2 (30x Earth value) (see review by Schubert et al. 2004). The supply of heat required to sustain such conditions is believed to come from tidal dissipation caused by orbital resonance between Io, Europa and Ganymede. This tidal heating is thought to lead to partial melting of the asthenosphere up to melt fractions of ~20%. These large melt fractions are higher than are thought possible on Earth and are likely permitted by the low gravity of Io, preventing compaction from being effective. Many questions surround the sub-surface relationships of Io's volcanos. At low latitudes volcanos appear to be uniformly distributed, maximising their separation from each other (Hamilton et al, 2013). This would imply that they are somehow interacting at depth, but this relationship is however not observed at higher latitudes. Computer models coupling tidal heating distribution within the body to melt formation and migration could help probe these intriguing observations. This would attempt to look at whether melt production beneath individual features was sufficient to support the volcanic output of the feature, and if not, how large a catchment area would be needed. The models could also help answer other mysteries surrounding Ionian volcanism, such as the apparently increased volcanism at low latitudes; the local correlation of mountains and volcanic features but lack of global correlation; potential temporal clustering of large volcanic 'outbursts'; and physical dynamics of 'top down tectonism'.Work up to this point surrounding Io has generally not coupled tidal heating, melt formation, and melt extraction with full thermo-dynamics and two-phase flow. Rather they have simplified one or more of these areas, in particular tending to simplify two-phase flow. This work would would look to tie these together along with new rheological considerations and tidal heating distribution calculations, revealed by recent papers (in particular Bierson and Nimmo, 2016).This project falls within the 'Astronomy and Space Science' research area of the STFC remit.