Previous studies have shown that Mt. Sharp has stratigraphic variation in mineralogy that may record a global transition from a climate more conducive to clay mineral formation to one marked by increased sulfate production. To better understand how small‐scale observations along the traverse path of NASA's Curiosity rover might be linked to such large‐scale processes, it is necessary to understand the extent to which mineral signatures observed from orbit vary laterally and vertically. This study uses newly processed visible‐shortwave infrared Compact Reconnaissance Imaging Spectrometer for Mars data and corresponding visible images to reexamine the mineralogy of lower Mt. Sharp, map mineral distribution, and evaluate stratigraphic relationships. We demonstrate the presence of darker‐toned strata that appears to be throughgoing with spectral signatures of monohydrated sulfate. Strata above and below this zone are lighter‐toned and contain polyhydrated sulfate and variable distribution of Fe/Mg clay minerals. Clay minerals are observed at multiple stratigraphic positions; unlike the kieserite zone these units cannot be traced laterally across Mt. Sharp. The kieserite zone appears to be stratigraphically confined, but in most locations the orbital data do not provide sufficient detail to determine whether mineral signatures conform to or cut across stratigraphic boundaries, leaving open the question as to whether the clay minerals and sulfates occur as detrital, primary chemical precipitates, and/or diagenetic phases. Future observations along Curiosity's traverse will help distinguish between these possibilities. Rover observations of clay‐bearing strata in northwest Mt. Sharp may be more reflective of local conditions that could be distinct from those associated with other clay‐bearing strata.

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关于下山矿物学的最新观点和假设。从轨道上看，锋利的火星

先前的研究表明，夏普的矿物学具有地层学变化，可能记录了从更有利于粘土矿物形成的气候向以硫酸盐产量增加为特征的气候向全球过渡的过程。为了更好地理解NASA好奇号火星探测器的遍历路径上的小规模观测值可能与如此大规模的过程相关联，有必要了解从轨道观察到的矿物特征在横向和垂直方向上变化的程度。这项研究使用新近处理的可见-短波红外紧凑侦察成像光谱仪获取火星数据和相应的可见图像，以重新检查较低Mt的矿物学。锐化，绘制矿物分布图并评估地层关系。我们证明了暗色调的地层的存在似乎正在经历一水合硫酸盐的光谱特征。该区域上方和下方的地层较浅，含有多水合硫酸盐和铁/镁粘土矿物的分布不均。在多个地层位置都可以观察到粘土矿物。与钾铁矿带不同的是，这些单元不能在Mt上横向追踪。锋利的。钾铁矿带似乎是地层限制的，但是在大多数位置，轨道数据不能提供足够的细节来确定矿物特征是否符合或跨越地层边界，这留下了关于粘土矿物和硫酸盐是否以碎屑形式存在的问题，初级化学沉淀和/或成岩相。好奇心的未来观察 遍历将有助于区分这些可能性。西北山的粘土层的流动站观测。夏普可能更能反映与其他含粘土地层不同的当地情况。