Ballistic Sedimentation of Impact Crater Ejecta: Implications for the Provenance of Lunar Samples and the Resurfacing Effect of Ejecta on the Lunar Surface
Ballistic Sedimentation of Impact Crater Ejecta: Implications for the Provenance of Lunar Samples and the Resurfacing Effect of Ejecta on the Lunar Surface
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撞击坑喷射物的弹道沉积：对月球样本来源和喷射物对月球表面的重铺作用的影响
DOI：
10.1029/2019je006113
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发表时间：
2020-05
影响因子：
3.9
通讯作者：
Xu Aoao
中科院分区：
文献类型：
--
作者：
Xie Minggang;Liu Tiantian;Xu Aoao
清楚地了解弹道沉积对于解释月球表面的演化和月球样品的来源至关重要。已经建立了定量模型来估计喷出物矿床的特征，例如远源喷出物的丰度与当地出土物质的数量的比较。本文通过考虑抛射物沉积物对后期抛射物就位过程的屏蔽作用，对先前建立的弹道沉积模型进行了修正。我们的模型表明，由于屏蔽效应，连续喷射物沉积物中被挖掘的局部物质与喷出物的比例随着距离母坑中心的增加而显著增加。模型导出的结果表明，盆地形成在连续喷射物沉积和近端轻平原内重新形成地表，但仅在远端部分重新形成地表；因此，在定年比最年轻的盆地、东方盆地或靠近大型陨石坑的单元更老的单元时，应考虑部分地表重铺效应。将我们的模型应用于阿波罗16号着陆点，我们发现阿波罗16号的风化层中有10%可能是Orientale起源，这与Imbrium（9%）和Serenitatis ejecta（10%）几乎相同。阿波罗16号风化层中最丰富的盆地喷射物来自Nectaris盆地（23%）。这些结果为解释阿波罗16号样本的来源提供了重要的约束。
A clear understanding of ballistic sedimentation is critical for interpreting the evolution of the lunar surface and the provenance of lunar samples. Quantitative models have been established to estimate the characteristics of ejecta deposits, such as the abundance of distantly sourced ejecta compared to the amount of excavated local materials. Here, we revise a previously established ballistic sedimentation model by considering the shielding effect of ejecta deposits on the emplacement process of later‐arriving ejecta. Our model shows that, due to the shielding effect, the ratio of excavated local materials to ejecta in continuous ejecta deposits increases significantly with increasing distance from the center of their parent crater. Model‐derived results imply that basin formation resurfaces regions within continuous ejecta deposits and proximal light plains but only partially resurfaces distal areas; thus, the partial resurfacing effect should be considered when dating units older than the youngest basin, Orientale, or units located close to large craters. Applying our model to the Apollo 16 landing site, we found that 10% of the Apollo 16 regolith may be of Orientale origin, which is almost the same as those of Imbrium (9%) and Serenitatis ejecta (10%). The most abundant basin ejecta in Apollo 16 regolith is from the Nectaris basin (23%). These results provide important constraints for interpreting the provenance of the Apollo 16 samples.
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影响因子：
5.2
作者：
C. Fassett;J. Head;David E. Smith;M. Zuber;G. Neumann
通讯作者：
C. Fassett;J. Head;David E. Smith;M. Zuber;G. Neumann
DOI：
10.1007/bf00567507
发表时间：
1975-07
期刊：
The moon
影响因子：
--
作者：
Yosio Nakamura;J. Dorman;F. Duennebier;D. Lammlein;G. Latham
通讯作者：
Yosio Nakamura;J. Dorman;F. Duennebier;D. Lammlein;G. Latham
DOI：
--
发表时间：
1977
期刊：
--
影响因子：
--
作者：
R. J. Pike
通讯作者：
R. J. Pike
影响因子：
--
作者：
P. Schultz;D. Gault
通讯作者：
P. Schultz;D. Gault
DOI：
10.1007/bf01877795
发表时间：
1974-10
期刊：
The moon
影响因子：
--
作者：
J. Head
通讯作者：
J. Head