Since early February 2019, the SEIS (Seismic Experiment for Interior Structure) seismometer deployed at the surface of Mars in the framework of the InSight mission has been continuously recording the ground motion at Elysium Planitia. In this study, we take advantage of this exceptional data set to put constraints on the crustal properties of Mars using seismic interferometry (SI). To carry out this task, we first examine the continuous records from the very broadband seismometer. Several deterministic sources of environmental noise are identified and specific preprocessing strategies are presented to mitigate their influence. Applying the principles of SI to the single‐station configuration of InSight, we compute, for each Sol and each hour of the martian day, the diagonal elements of the time‐domain correlation tensor of random ambient vibrations recorded by SEIS. A similar computation is performed on the diffuse waveforms generated by more than a hundred Marsquakes. A careful signal‐to‐noise ratio analysis and an inter‐comparison between the two datasets suggest that the results from SI are most reliable in a narrow frequency band around 2.4 Hz, where an amplification of both ambient vibrations and seismic events is observed. The average autocorrelation functions (ACFs) contain well identifiable seismic arrivals, that are very consistent between the two datasets. Interpreting the vertical and horizontal ACFs as, respectively, the P‐ and S‐ seismic reflectivity below InSight, we propose a simple stratified velocity model of the crust, which is mostly compatible with previous results from receiver function analysis. Our results are discussed and compared to recent works from the literature.

中文翻译：

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SEIS-InSight地震仪在火星上记录的地面振动的自相关

自2019年2月上旬以来，在InSight任务框架内部署在火星表面的SEIS（内部结构地震实验）地震仪一直在连续记录Elysium Planitia的地面运动。在这项研究中，我们利用这一特殊的数据集，通过地震干涉法（SI）对火星的地壳特性施加了约束。为了执行此任务，我们首先检查超宽带地震仪的连续记录。确定了几种确定性的环境噪声源，并提出了特定的预处理策略来减轻其影响。将SI原理应用到InSight的单站配置中，我们针对火星日的每个Sol和每个小时计算一次，SEIS记录的随机环境振动的时域相关张量的对角元素。对由一百多个Marsquakes产生的扩散波形执行类似的计算。仔细的信噪比分析和两个数据集之间的比较表明，SI的结果在2.4 Hz附近的窄频带中最为可靠，在该频带中观察到了周围振动和地震事件的放大。平均自相关函数（ACF）包含可很好识别的地震波到达，这两个数据集之间非常一致。解释垂直和水平ACF分别为InSight下的P和S地震反射率，我们提出了一个简单的地壳分层速度模型，这与接收器功能分析的先前结果基本兼容。我们的结果进行了讨论，并与文献中的最新作品进行了比较。