论文标题
早期强烈轰击对大型巨石进化和月球（和行星）表面样品的影响
Effects of early intense bombardment on megaregolith evolution and on lunar (and planetary) surface samples
论文作者
论文摘要
太阳系的前500 MYR的影响率对于了解月球地质历史的理解至关重要，但它们一直有争议。早期月球围墙的广泛接受的，后的后范式（1975-2014）提议在从积聚（> 4.4 GA）到4.0 GA的时期内非常低或可以忽略不计的影响，然后是17000万年的17000万年度飙升，对灾难性的多个型号造成了更大的趋势，这是在逐渐造成的，这是在3.日期内的3.型号，在3.型号上均构造了3.型号。提出非常早期的强烈影响率，在整个期间从积聚到年龄约为3.0 GA。这些模型消除了盆地形成的尖峰。这种转移对当今月球表面可以收集的岩石样品的巨型演化和岩石样品的特性具有重要的后果。我们采用Morbidelli等。 （2018）早期强烈轰炸的“积尾”模型，随着时间的变化而下降。我们发现效果与以前的模型不同：早期的陨石坑饱和和过饱和；岩浆海洋凝固的干扰；深层早期的大型巨石；以及最早的多环盆地的侵蚀性破坏，其影响融化和它们的喷射毯子。 Our results explain observations such as differences in numbers of early lunar impact melts vs. numbers of early igneous crustal rocks, highland breccias containing impact melts as old as 4.35 Ga, absence of a 170 Myr-long spike in impact melt ages at 3.9 Ga among lunar and asteroidal meteorites, and GRAIL observations of lunar crustal structure.
Impact rates in the first 500 Myr of the solar system are critical to an understanding of lunar geological history, but they have been controversial. The widely accepted, post-Apollo paradigm of early lunar impact cratering (ca. 1975-2014) proposed very low or negligible impact cratering in the period from accretion (>4.4 Ga) to about 4.0 Ga ago, followed by a 170-million-year-long spike of cataclysmic cratering, during which most prominent multi-ring impact basins formed at age of about 3.9 Ga. More recent dynamical models suggest very early intense impact rates, declining throughout the period from accretion until an age of about 3.0 Ga. These models remove the basin-forming spike. This shift has important consequences on megaregolith evolution and properties of rock samples that can be collected on the lunar surface today. We adopt the Morbidelli et al. (2018) "accretion tail" model of early intense bombardment, declining as a function of time. We find effects differing from the previous models: early crater saturation and supersaturation; disturbance of magma ocean solidification; deep early megaregolith; and erosive destruction of the earliest multi-ring basins, their impact melts, and their ejecta blankets. Our results explain observations such as differences in numbers of early lunar impact melts vs. numbers of early igneous crustal rocks, highland breccias containing impact melts as old as 4.35 Ga, absence of a 170 Myr-long spike in impact melt ages at 3.9 Ga among lunar and asteroidal meteorites, and GRAIL observations of lunar crustal structure.
