Here, we calculate the mineralogy of the Martian lower crust and upper mantle as a function of pressure and temperature with depth using four bulk compositions (average crust, Gusev basalt, olivine‐phyric shergottite, and primitive average mantle). We then use this mineralogy to extract rock properties such as density and seismic velocities, describe their changes with varying conditions and geotherms, and make predictions for the crust–mantle boundary. Mineralogically, all compositions produce garnet, orthopyroxene, clinopyroxene in varying proportions at high pressures, with differences in minor minerals (spinel, ilmenite, rutile, and/or K‐feldspar). According to our calculations, the average crust and Gusev basalt compositions have the potential to yield higher densities than the average mantle composition, particularly for thicker crusts and/or colder geotherms. Therefore, recycling of the Martian crust into the mantle could occur through the process of crustal delamination, if not kinetically inhibited. However, our results show that, depending on crustal thickness, the crust may not be easily distinguishable from the mantle in seismic properties.

中文翻译：

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火星地壳的高压变质矿物学对密度和地震剖面的影响

在这里，我们使用四种整体成分（平均地壳、古谢夫玄武岩、橄榄石-岩层辉长岩和原始平均地幔）计算火星下地壳和上地幔的矿物学作为压力和温度与深度的函数。然后，我们使用这种矿物学来提取岩石特性，例如密度和地震速度，描述它们在不同条件和地温下的变化，并对壳幔边界进行预测。在矿物学上，所有成分在高压下都会产生不同比例的石榴石、斜方辉石、单斜辉石，在微量矿物（尖晶石、钛铁矿、金红石和/或钾长石）方面存在差异。根据我们的计算，平均地壳和 Gusev 玄武岩成分有可能产生比平均地幔成分更高的密度，特别是对于较厚的地壳和/或较冷的地温。因此，即使没有动力学抑制，火星地壳也可能通过地壳分层过程再循环到地幔中。然而，我们的结果表明，根据地壳厚度，地壳在地震性质上可能不容易与地幔区分开来。