用近红外及短波红外反射波谱编码方法识别蚀变粘土矿物

本文介绍一种根据蚀变粘土矿物的近红外及短波红外反射波谱的特征吸收峰识别粘土矿物的方法。该方法的原理是根据不同蚀变粘土矿物的近红外、短波红外反射波谱均存在一些特征吸收峰,而且不同粘土矿物,其吸收峰个数、波长位置及吸收强度不同。首先用IRIS红外智能波谱仪对样品进行测试,然后,将测得的样品的近红外、短波红外反射波谱吸收峰波长和吸收强度进行数字编码,再用此编码与存贮于数据库中的标准蚀变粘土矿物的近红外-短波红外反射波谱吸收峰波长和吸收强度编码进行对比,来进行矿物识别。该方法主要包括①求外壳曲线(包络曲线);②求外壳系数；③求吸收峰极小值及波长位置；④对吸收峰波长及吸收强度进行编码；⑤与标准蚀变粘土矿物吸收峰波长和吸收强度编码进行对比来识别粘土矿物等5个步骤。

THE IDENTIFICATION METHOD OF ALTERATED CLAY MINERALS ACCORDING TO THE SPECTRA IN THE NEAR INFRARED AND SHORTWAVE INFRARED REGIONS

Abstract This paper presents a spectral identification method of the alterated clay minerals,according to their spectral characteristic absorption in the Near Infrared and Short-Wave Infrared(NIR-SWIR). The principle of this method is that the spectra in the NIR-SWIR have a certain characteristic absorptions and the number of absorptions, the position of wavelength and the strength of an absorption are different on the basis of the different alterated clay minerals. Therefore, measuring the spectral absorptions wave length and strength of the samples may identificate the alterated clay minerals.At first, the spectra of the sample are measured with the IRIS Spectroradiometer in this method. The characteristic absorptions wavelength and strength of the measured sample spectrum in the NIR-SWIR are then encoded. Finally, minerals identification will be done by using the code comparison with the spectral codes of the standard alterated clay minerals stored in the data base.This method includes the calculation the hull curve, computing the hull quotient,detecting absorption minima point and corresponding wavelength position, encoding to the absorption wavelength and strength, and minerals identification by code matching.