Comparisons of the core and mantle compositions of earth analogs from different terrestrial planet formation scenarios
Comparisons of the core and mantle compositions of earth analogs from different terrestrial planet formation scenarios
复制标题
不同类地行星形成情景中地球类似物的核心和地幔成分比较
DOI：
10.1016/j.icarus.2023.115425
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发表时间：
2023
期刊：
影响因子：
3.2
通讯作者：
Raymond, Sean N.
中科院分区：
文献类型：
--
作者：
Gu, Jesse T.;Fischer, Rebecca A.;Brennan, Matthew C.;Clement, Matthew S.;Jacobson, Seth A.;Kaib, Nathan A.;O'Brien, David P.;Raymond, Sean N.
地核和地幔的化学成分为我们了解它们形成的过程提供了线索。另一方面，n体模拟通常不包含化学信息，而只是试图重现类地行星的质量和轨道。这些模拟可以分为四种可能可行的太阳系形成情景（经典、环空、大Tack和早期不稳定），为此我们总共编制了433n个天体模拟。我们将这些模拟的结果与地核和地幔的化学性质联系起来，使用熔融结垢定律结合地核形成的多阶段模型。我们发现地球类似物的组成在很大程度上受平衡胚核分数（kcore_emb）和n -体模拟中初始胚质量的控制，而不是模拟类型，在模拟类型中，较高的kcore_emb值和较大的初始胚质量对应于地球模拟地幔中较高的Ni， Co， Mo和W浓度以及地球模拟核中较高的Si和O浓度。因此，较大的初始胚胎质量需要较小的kcore_emb值来匹配地球的地幔组成。另一方面，地球模拟地核的组成对吸积物质的平衡温度和fo2敏感。在考虑岩浆海洋的寿命时，模拟类型可能很重要，其中Grand Tack模拟在最后一次巨大撞击后增加了最多的物质。然而，由于地幔成分对不同参数的敏感性和n -体模拟的随机性，我们不能排除任何吸积情景或初始胚胎质量。我们使用我们编译的模拟来探索初始胚胎质量与地球类似物融化历史之间的关系，其中撞击时间，岩浆海洋寿命和挥发性释放之间的复杂相互作用可能影响由不同模拟类型形成的地球类似物的成分。将地球类似物所经历的最后一次胚胎撞击与具体的月球形成情景进行比较，我们发现月球形成撞击的特征取决于n体模拟中的初始条件，其中较大的初始胚胎质量促进较大和较慢的月球形成撞击。火星大小的初始胚胎最符合典型的撞到固体地幔上就跑的情况。我们的研究结果表明，在n体模拟中限制平衡撞击体核心（kcore）的比例和初始胚胎质量对于理解地球的吸积历史和月球形成的影响特征具有重要意义。
The chemical compositions of Earth's core and mantle provide insight into the processes that led to their formation.N-body simulations, on the other hand, generally do not contain chemical information, and seek to only reproduce the masses and orbits of the terrestrial planets. These simulations can be grouped into four potentially viable scenarios of Solar System formation (Classical, Annulus, Grand Tack, and Early Instability) for which we compile a total of 433N-body simulations. We relate the outputs of these simulations to the chemistry of Earth's core and mantle using a melt-scaling law combined with a multi-stage model of core formation. We find the compositions of Earth analogs to be largely governed by the fraction of equilibrating embryo cores (kcore_emb) and the initial embryo masses inN-body simulations, rather than the simulation type, where higher values ofkcore_emband larger initial embryo masses correspond to higher concentrations of Ni, Co, Mo, and W in Earth analog mantles and higher concentrations of Si and O in Earth analog cores. As a result, larger initial embryo masses require smaller values ofkcore_embto match Earth's mantle composition. On the other hand, compositions of Earth analog cores are sensitive to the temperatures of equilibration andfO2of accreting material. Simulation type may be important when considering magma ocean lifetimes, where Grand Tack simulations have the largest amounts of material accreted after the last giant impact. However, we cannot rule out any accretion scenarios or initial embryo masses due to the sensitivity of Earth's mantle composition to different parameters and the stochastic nature ofN-body simulations. We use our compiled simulations to explore the relationship between initial embryo masses and the melting history of Earth analogs, where the complex interplay between the timing between impacts, magma ocean lifetimes, and volatile delivery could affect the compositions of Earth analogs formed from different simulation types. Comparing the last embryo impacts experienced by Earth analogs to specific Moon-forming scenarios, we find the characteristics of the Moon-forming impact are dependent on the initial conditions inN-body simulations where larger initial embryo masses promote larger and slower Moon-forming impactors. Mars-sized initial embryos are most consistent with the canonical hit-and-run scenario onto a solid mantle. Our results suggest that constraining the fraction of equilibrating impactor core (kcore) and the initial embryo masses inN-body simulations could be significant for understanding both Earth's accretion history and characteristics of the Moon-forming impact.
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影响因子：
5.3
作者：
Andrault, Denis;Bolfan-Casanova, Nathalie;Mezouar, Mohamed
通讯作者：
Mezouar, Mohamed
月球的陆地岩浆海洋起源
影响因子：
18.3
作者：
Hosono;N.;Karato;S.;Makino;J.;Saitoh;TR.
通讯作者：
TR.
月球的多重撞击起源
DOI：
--
发表时间：
2017
期刊：
影响因子：
--
作者：
R. Rufu;O. Aharonson;H. Perets
通讯作者：
H. Perets
影响因子：
5.3
作者：
Kendall, Jordan D.;Melosh, H. J.
通讯作者：
Melosh, H. J.
影响因子：
5.3
作者：
Landeau, Maylis;Deguen, Renaud;Dalziel, Stuart B.
通讯作者：
Dalziel, Stuart B.