摘要
Hapke岩矿二向反射率光谱定量模型是研究混合矿物光谱的有利工具,而国内对该模型的基础研究较少。通过4组室内混合矿物光谱数据来研究该模型在模拟混合矿物光谱时的准确性与存在的问题,进而探讨混合矿物光谱的特征规律。研究表明,在模拟混合矿物光谱方面不论是各向同性,还是各向异性的Hapke模型均有很高的精度,权重调整后4组各向同性模型的模拟结果均方根误差(RMSE)均值为0.014 4,相关系数(R)均值为0.994 7,4组各向异性模型的模拟结果 RMSE均值为0.008 4,R均值为0.994 4,说明该模型是优异的混合光谱分析手段;但模型对暗色矿物适用性较差,如当混合矿物中含有黑云母时模拟精度较低;混合矿物的光谱谱形需要针对矿物组成进行具体分析,其中所占质量分数较高的矿物并不一定能主导混合矿物的光谱谱形,而低反射率的矿物在混合矿物光谱中发挥的作用远大于其质量分数的比重。
Hapke photometric model is a useful tool for studying the spectra of mixed minerals. However,there are still some improvable things,and domestic research still lags far behind that of foreign countries. This paper focuses on the characteristics of surface minerals through 4 groups of spectroscopic tests in laboratory,and then discusses and points out the accuracy of the Hapke photometric model when simulating the spectra of mixed minerals. The mean of root mean square errors( RMSE) of the 4 groups by using IMSA model is 0. 014 4,and the mean of correlation coefficients( R) is 0. 994 7. The mean of RMSE of the 4 groups by using AMSA model is 0. 008 4,and the mean of R is 0. 994 4. These data suggest that IMSA model and AMSA model have a very high precision and can be a good means to simulate spectral mixture of mixed minerals. Nevertheless,the experiment results show that,when the mixed minerals contain biotite,the accuracy is not satisfactory,but the accuracy of simulation can be improved by adjusting the weight of biotite. Spectral shape of mixed minerals needs a specific analysis of compositions of the mixed mineral,for instance,a particular mineral which possesses a higher mass fraction in the mixed minerals may not play the leading role in the spectral shape,while the mineral of low reflectivity may play a more important role.
引文
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