Spectral and mineralogical analyses were performed using nine naturally hydrated and dehydrated carbonaceous chondrite samples which were classified into heating stages (HS) from I to IV based on previous X-ray diffraction results. In-situ heating of samples at 120–400 °C was performed during spectral measurements and successfully removed absorbed water and part of rehydrated water from chondrite samples. Reflectance spectra of HS-I samples show the positive slope in visible (Vis)-infrared (IR) range and the significant 0.7- and 3-μm absorption bands. The 0.7-μm band appears in only HS-I sample spectra. With increasing temperature of heating, (1) Vis-IR slope decreases, (2) the 3-μm band becomes shallower, and (3) Christiansen feature (CF) and Reststrahlen bands (RB) shift toward longer wavelength. TEM-EDX analyses showed that the matrix of strongly-heated chondrites consists of tiny olivine, low-Ca pyroxene, and FeNi metallic particles mostly smaller than 100 nm in diameter, instead of Fe-rich serpentines and tochilinite observed in the HS-I chondrite. Therefore, in proportion to the heating degree, amorphization and dehydration of serpentine and tochilinite from HS-I to HS-II may cause the 0.7- and 3-μm band weakening, spectral bluing and darkening of chondrite spectra. In addition, formation of secondary anhydrous silicates and FeNi-rich metal grains at HS-IV would be responsible for the 3-μm band depth decrease, spectral reddening and brightening, CF peak shift, and RB changes of chondrite spectra. Those spectral changes in response to mineralogical alteration processes will be useful to interpret planetary surface composition by remote-sensing observations using ground-based or airborne/space telescopes or spacecraft missions.

使用九个天然水合和脱水的碳质球粒陨石样品进行光谱和矿物学分析，这些样品根据先前的 X 射线衍射结果分为 I ​​至 IV 加热阶段 (HS)。原位在光谱测量过程中将样品加热到 120-400°C，并成功地去除了球粒陨石样品中的吸收水和部分再水化水。HS-I 样品的反射光谱显示可见 (Vis)-红外 (IR) 范围内的正斜率和显着的 0.7- 和 3-μm 吸收带。0.7-μm 波段仅出现在 HS-I 样品光谱中。随着加热温度的升高，(1) Vis-IR 斜率减小，(2) 3-μm 波段变浅，(3) Christiansen 特征 (CF) 和 Reststrahlen 波段 (RB) 向更长波长移动。TEM-EDX 分析表明，强加热球粒陨石的基质由微小的橄榄石、低钙辉石和直径大多小于 100 nm 的 FeNi 金属颗粒组成，而不是在 HS-I 球粒陨石中观察到的富铁蛇纹石和 tochilinite . 所以，与加热程度成正比，蛇纹石和蛇纹石从HS-I到HS-II的非晶化和脱水可能导致球粒陨石光谱的0.7-和3-μm带减弱，光谱发蓝和变暗。此外，HS-IV 处二次无水硅酸盐和富含 FeNi 的金属晶粒的形成将导致球粒陨石光谱的 3 μm 带深度减小、光谱变红和变亮、CF 峰位移和 RB 变化。这些响应矿物学变化过程的光谱变化将有助于通过使用地面或机载/太空望远镜或航天器任务的遥感观测来解释行星表面成分。球粒陨石光谱的光谱发蓝和变暗。此外，HS-IV 处二次无水硅酸盐和富含 FeNi 的金属晶粒的形成将导致球粒陨石光谱的 3 μm 带深度减小、光谱变红和变亮、CF 峰位移和 RB 变化。这些响应矿物学变化过程的光谱变化将有助于通过使用地面或机载/太空望远镜或航天器任务的遥感观测来解释行星表面成分。球粒陨石光谱的光谱发蓝和变暗。此外，HS-IV 处二次无水硅酸盐和富含 FeNi 的金属晶粒的形成将导致球粒陨石光谱的 3 μm 带深度减小、光谱变红和变亮、CF 峰位移和 RB 变化。这些响应矿物学变化过程的光谱变化将有助于通过使用地面或机载/太空望远镜或航天器任务的遥感观测来解释行星表面成分。