Abstract We obtained mid-infrared reflectance spectra of powdered size fractions (0–25 μm, 25–63 μm, 63–125 μm and 125–250 μm) of 5 carbonaceous chondrites HaH 280 (CK4), Allende (CV3), NWA 10574 (CM2) and Murchison (CM2), and C2 (ungrouped) Tagish Lake. In addition, in-situ micro-FTIR reflectance spectra of CAIs in Allende, Ornans and Vigarano have been made. These spectra are part of a database for the comparison with remote sensing data of asteroids and planetary bodies, but also for laboratory studies of meteorites. Carbonaceous chondrites HaH 280 (CK4), Allende (CV3) and NWA 10574 (CM2) show mid-IR spectra with Reststrahlen bands (RB) dominated by forsterite and pyroxene features. The transparency features (TF) are at 12.1 μm–12.9 μm and the Christiansen features (CF) at 8.5 μm–9.3 μm. Murchison (CM2) and ungrouped Tagish Lake (C2) show mainly phyllosilicate features in their spectra. The CF is between 8.6 μm and 9.0 μm. Micro-FTIR spectra of CAIs from Allende, Vigarano, and Ornans have spinel features between 14.1 μm and 14.3 μm. In addition, melilite was identified in the Vigarano and Ornans samples with characteristic features at 11.7 μm and 12.4 μm. Nepheline and sodalite features have been identified around 14 μm in the Allende CAI as alteration phases resulting from thermal metamorphism. A band shift in spinel with increasing Fe content from thermal metamorphism could be spectral indicator for parent body metamorphism. A comparison with other bulk samples from the same meteorites/type shows high similarity. Comparison of the finest size fractions modelled in emissivity with remote sensing data of asteroids shows some similarity between a linear mixture of Allende and Murchison and the spectra of asteroid 253 Mathilde. However, the main 10 μm plateau is clearly shifted by 0.5 μm between asteroid and meteorite spectra. Also, the general band shapes are different. Differences between asteroidal environment (e.g. fairy castle structure) and laboratory make direct comparisons difficult.

中文翻译：

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碳质球粒陨石和富钙铝包裹体的中红外反射光谱

摘要 我们获得了 5 种碳质球粒陨石 HaH 280 (CK4)、阿连德 (CV3)、NWA 10574 的粉末粒度部分（0-25 μm、25-63 μm、63-125 μm 和 125-250 μm）的中红外反射光谱(CM2) 和默奇森 (CM2)，以及 C2（未分组的）塔吉什湖。此外，还制作了阿连德、奥尔南和维加拉诺 CAI 的原位微红外反射光谱。这些光谱是用于与小行星和行星体的遥感数据进行比较的数据库的一部分，也用于陨石的实验室研究。碳质球粒陨石 HaH 280 (CK4)、阿连德 (CV3) 和 NWA 10574 (CM2) 显示中红外光谱，其中 Reststrahlen 带 (RB) 以镁橄榄石和辉石特征为主。透明度特征 (TF) 为 12.1 μm–12.9 μm，Christiansen 特征 (CF) 为 8.5 μm–9.3 μm。Murchison (CM2) 和未分组的 Tagish Lake (C2) 在其光谱中主要显示出页硅酸盐特征。CF 在 8.6 μm 和 9.0 μm 之间。来自 Allende、Vigarano 和 Ornans 的 CAI 的微 FTIR 光谱具有介于 14.1 μm 和 14.3 μm 之间的尖晶石特征。此外，在 Vigarano 和 Ornans 样品中鉴定出黄长石，其特征为 11.7 μm 和 12.4 μm。在阿连德 CAI 中，霞石和方钠石特征已被确定为由热变质作用引起的蚀变相，大约为 14 微米。随着热变质作用中铁含量的增加，尖晶石中的带移可能是母体变质作用的光谱指标。与来自相同陨石/类型的其他大块样品的比较显示出高度相似性。以发射率建模的最细粒度分数与小行星遥感数据的比较表明，阿连德和默奇森的线性混合物与小行星 253 Mathilde 的光谱之间存在一些相似性。然而，主要的 10 μm 高原在小行星和陨石光谱之间明显偏移了 0.5 μm。此外，一般的带形状是不同的。小行星环境（例如童话城堡结构）和实验室之间的差异使得直接比较变得困难。