The characterization of the megaregolith on the Moon has been investigated in various ways including analysis of lunar meteorites, remote sensing of mineralogy and gravity, and deriving a seismic velocity profile. In this study, we propose a method for analyzing azimuthal anisotropy of the megaregolith. We call this method deep‐moonquake seismic interferometry applied to S‐wave coda (DMSI‐S). DMSI‐S can turn the records of deep moonquakes into recordings from virtual active sources. The retrieved virtual sources coincide with the station positions, and thus, we obtain virtual zero‐offset (pulse‐echo) measurements. DMSI‐S is applied to seven clusters of deep moonquakes recorded at the Apollo 14 landing site, resulting in virtual zero‐offset measurements at the Apollo station 14. We use the S‐wave recordings retrieved from DMSI‐S to analyze azimuthal anisotropy. We find weak anisotropy at the layer where the megaregolith is assumed to be present. We interpret our result to show that the megaregolith at this site is characterized by a layer (or layers) of impact material, following the Imbrium impact, with internal alignment of the crushed material.

中文翻译：

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阿波罗14号登陆点巨巨石的方位各向异性。

已经通过各种方法研究了月球上巨巨石的特征，包括分析月球陨石，遥感矿物学和重力以及推导出地震速度剖面。在这项研究中，我们提出了一种分析巨灰岩方位各向异性的方法。我们称这种方法为适用于S波尾声（DMSI-S）的深地震地震干涉法。DMSI‐S可以将深度地震的记录转换成来自虚拟活跃源的记录。检索到的虚拟源与测站位置一致，因此，我们获得了虚拟零偏移（脉冲回波）测量值。DMSI‐S适用于在阿波罗14号登陆点记录的七个深月震群，从而在阿波罗14号站进行了虚拟零偏移量测量。我们使用S从DMSI-S中检索来的波浪记录，以分析方位各向异性。我们在假定存在巨灰岩的层上发现了较弱的各向异性。我们解释我们的结果，以表明在该位置处的巨灰岩的特征是在受到Imbrium冲击后，一层或多层冲击材料与压碎材料的内部对齐。