Melting in super-earths
Melting in super-earths
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融化在超级地球中
DOI：
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
L. Stixrude
中科院分区：
文献类型：
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作者：
L. Stixrude
我们研究了岩石 - 铁超级地球中可能的熔化程度，重点关注位于宜居带的那些超级地球。我们考虑了吸积和核心形成的能量学、冷却的时间尺度及其对黏度和部分熔化的依赖性、通过黏度的温度依赖性进行的热调节，以及超级地球所特有的超高压下岩石和铁成分的熔化曲线。我们发现，吸积过程中动能沉积的效率随行星质量增加；考虑到巨大撞击和核心形成可能起到的作用，我们发现超级地球很可能在完全熔化的状态下完成其吸积阶段。对热调节的考虑使我们提出了由硅酸盐熔化控制的超级地球的模型温度剖面。我们根据现有的实验和从头算结果以及标度定律，估算了铁和岩石成分直至超级地球内部所特有的极端压力下的熔化曲线。我们通过求解质量守恒方程和流体静力平衡方程，以及岩石和铁成分的状态方程来构建超级地球的热模型。我们将核幔边界和表面的位温设定为当地的硅酸盐熔化温度。我们发现古老的（约40亿年）超级地球在地幔的顶部和底部可能是部分熔化的，并且地幔对流足够强烈，足以在超级地球质量的整个范围内维持发电机作用。
We examine the possible extent of melting in rock-iron super-earths, focusing on those in the habitable zone. We consider the energetics of accretion and core formation, the timescale of cooling and its dependence on viscosity and partial melting, thermal regulation via the temperature dependence of viscosity, and the melting curves of rock and iron components at the ultra-high pressures characteristic of super-earths. We find that the efficiency of kinetic energy deposition during accretion increases with planetary mass; considering the likely role of giant impacts and core formation, we find that super-earths probably complete their accretionary phase in an entirely molten state. Considerations of thermal regulation lead us to propose model temperature profiles of super-earths that are controlled by silicate melting. We estimate melting curves of iron and rock components up to the extreme pressures characteristic of super-earth interiors based on existing experimental and ab initio results and scaling laws. We construct super-earth thermal models by solving the equations of mass conservation and hydrostatic equilibrium, together with equations of state of rock and iron components. We set the potential temperature at the core–mantle boundary and at the surface to the local silicate melting temperature. We find that ancient (∼4 Gyr) super-earths may be partially molten at the top and bottom of their mantles, and that mantle convection is sufficiently vigorous to sustain dynamo action over the whole range of super-earth masses.
超级地球中的地幔动力学：后钙钛矿流变学和粘度的自我调节
影响因子：
3.2
作者：
Tackley P
通讯作者：
Tackley P
类地行星在核心形成过程中通过负底辟作用进行热分配
影响因子：
5.3
作者：
H. Samuel;P. J. Tackley;M. Evonuk
通讯作者：
M. Evonuk