论文标题
使用FTIR，TGA和RAMAN光谱法及其CM分类，对Mukundpura（MK）碳质软管的水性改变研究
Aqueous Alteration Studies on Mukundpura (MK) Carbonaceous Chondrite using FTIR, TGA and Raman spectroscopy and its CM classification
论文作者
论文摘要
FTIR跌落后立即对MK进行测量，显示了一个唯一的双线尺寸，大约10千分尺，与许多普通的CM2软骨岩有显着不同，在该列中仅观察到大约10毫米的单线。同样，MK中的一个非常微弱的11.2千分尺表明，由于父母的严重水改变，无水硅酸盐，橄榄石，因此无水硅酸盐的完全蛇纹石化。拉曼研究表明，在0°C左右的峰值变质温度较低，并且与在较高温度下形成的FTIR光谱中的峰值相对应。在24小时内进行了第一个热重测量。 MK跌落的速度，显示在400-770°C范围内体重减轻10％，并且在30个月后的另一批MK片段上与TGA一致，这证实了对与水合粘土结合的水的影响。这种巨大的体重减轻还排除了MK遭受的任何水后变化事件，并表示存在水合粘土的存在。 MGO/FEO的测得比率约为0.56，硫的重量为3.4％。最近，仅基于Potin等人的水性改变。 （Potin等，2020），将MK分类为CM1，这意味着MK应该是最大的CM，而Ray等人。 （Ray等人2018），等同于巴黎（例如（CM2.7）），最小水改变。但是，如果我们结合观察到的水位变化，MGO/FEO重量比和硫的重量％将对MK提供更全面的理解，因此，我们将其归类为CM2.3.INSTED CM1或CM（2.7-2.9）。
FTIR measurement on MK immediately after its fall, shows a unique doublet around 10 micrometer, significantly different from many ordinary CM2 chondrites, where only a singlet around 10 micrometer is observed. Also, a very faint 11.2 micrometer feature in MK indicates the absence of anhydrous silicates, olivine and thus complete serpentinization of anhydrous silicates due to severe aqueous alteration on parent body. Raman studies show a low peak metamorphic temperature around 0 °C and consistent with the absence of peak corresponding to tochilinite in FTIR spectrum, which forms at higher temperature. The first thermogravimetric measurement was carried out within 24 hrs. of MK fall, showing 10% weight loss in 400-770 °C range and is consistent with TGA on another MK fragment of same batch after 30 months, confirming no environmental impact on the water bound to hydrated clay. This large weight loss also rules out any post aqueous alteration thermal event suffered by MK and signify the presence of hydrated clay. The measured ratio of MgO/FeO is about 0.56, and sulfur weight is 3.4 %. Recently, based on only aqueous alteration Potin et al. (Potin et al. 2020), classified MK as CM1, implying MK should be utmost altered CM, whereas Ray et al. (Ray et al 2018), as equivalent to Paris like (CM2.7), least aqueous altered. However, if we combine the observed aqueous alteration, MgO/FeO weight ratio, and sulfur weight % together will provide a more comprehensive understanding for MK, and thus, we classify it as CM2.3.insted CM1 or CM(2.7-2.9).
