摘要
岩矿的反射光谱是进行岩矿分类与定量分析的重要依据,而颗粒度是影响光谱反射率的关键因素之一,探究不同颗粒度对岩矿反射光谱的影响至关重要。为了揭示颗粒度对赤铁矿反射光谱的影响规律,以巴西高品位赤铁矿为研究对象,利用SVC HR-1024光谱仪对不同颗粒度的样品进行可见光—近红外光谱测试,分析了赤铁矿样品的光谱反射率随着颗粒度的变化规律。研究表明:0.07~3.00 mm颗粒度范围内赤铁矿样品的光谱反射率随着颗粒度变化较小,且无明显规律;颗粒度为0.04~0.07 mm时,颗粒度对于光谱的影响主要体现在1 000~2 500 nm范围的近红外波段,颗粒度与反射率呈负相关关系;当颗粒度<0.04 mm时,样品光谱反射率发生突然性升高,在红光波段(620~760 nm)的反射峰突显,使得样品呈现明显的砖红色,同时在850~1 200 nm波段。光谱曲线出现陡边,反射率增加加快。试验结果很好地解释了赤铁矿在块状呈现钢灰色而在粉末状呈现红色的原因,同时也为提高铁矿遥感分类和定量反演精度提供了参考。
Reflectance spectrum is an important basis for classification and quantitative analysis of rocks and minerals,and particle size is one of the key factors affecting it. Therefore,it is vital to explore the influence of different particle sizes on reflectance spectrum. In order to reveal the influence law of granularity on hematite reflection spectrum,taking Brazilian highgrade hematite as an example,the visible-near infrared spectrals of hematite samples with different particle sizes were tested by SVC HR-1024,analyzing the variation of spectral reflectance of hematite samples with particle size. The study results showed that the spectral reflectance of hematite samples varied little and had no rule with the particle size in the 0. 07 ~ 3. 00 mm range. When the particle size was in the 0. 04~0. 07 mm range,the 1 000~2 500 nm range near infrared spectrum was greatly affected,with a significant negative correlation. When the particle size was less than 0. 04 mm,the spectral reflectance increased suddenly,and the reflection peak was obvious in the red band(620~760 nm),making the sample appear brick red.Meanwhile,in the 850~1 200 nm range,the spectral curve showed a steep edge and the increase of reflectance was accelerated. The test results effectively explain the reason why hematite appears steel gray in block and red in powder,and also provide referece for improving the remote sensing classification and quantitative inversion accuracy of iron ore.
作者
刘海琪
刘善军
丁瑞波
LIU Haiqi;LIU Shanjun;DING Ruibo(School of Resources and Civil Engineering,Northeastern University,Shenyang 110819,China)
出处
《金属矿山》
CAS
北大核心
2022年第4期158-162,共5页
Metal Mine
基金
国家自然科学基金项目(编号:41771404)。
关键词
赤铁矿
可见光—近红外光谱
颗粒度
光谱反射率
影响规律
high grade hematite
visible-near infrared spectrum
particle size
spectral reflectance
influence rule
