硅化带是多个矿种的找矿指示性信息，快速地大面积探测硅化带信息是遥感技术在地质找矿应用领域一项重要的应用。随着遥感技术的不断发展，针对不同的遥感数据，出现了多种不同的硅化带提取方法。首先通过分析 JHU（约翰霍普金斯大学）波谱库中10多种不同 SiO2的岩性光谱特征，研究与 SiO2含量密切相关的波段；其次，使用热红外地面光谱仪102F实测的样品光谱和样品的地球化学数据（SiO2含量），通过线性回归方程统计出 SiO2含量的计算公式；最后，使用该公式对 TA－SI 航空高光谱热红外数据进行处理，获取研究区 SiO2含量图，提取高 SiO2条带；并在进行野外验证。实验结果表明：8.62μm和9.25～9.5μm 是 SiO2含量相关性极大的波段；TASI（thermal airborne hyperspectral imager ）数据中有多个 SiO2对应的波谱特征，B6（8.62μm）的发射峰、B6两侧的斜坡及 B14、B17左侧的斜坡与 SiO2呈正相关关系；该方法提取研究区高 SiO2条带非常精确，在花岗岩区亦能识别出硅化带。%Silicified zone is close to several kinds of ores , and extracting spectral information of silification fast and largely is a significant application of remote sensing in geological prospecting .With the development of remote sensing technology, kinds of methods are proposed to extract silicified zone because of different data .Firstly,more than 10 kinds of rocks with different SiO 2 of JHU (Johns Hopkins University ) Spectral Library were analyzed, and point out several bands which are closely related to SiO 2 content.Secondly, 102F was used to measure spectrum of samples and formula to compute SiO 2 was obtain by linear regression with the spectrum and SiO 2 content of sam-ples.Finally, TASI data was used to extract silicified zone to verify the relation between the bands and SiO 2 con-tent, SiO2 content map of study area was obtained , high SiO2 belts were extracted from the map and field work prove that they are right.Thus, conclusions are drawn that (1)8.62 μm and 9.25-9.5 μm are closely related to SiO2 content, (2)that several spectral feature of SiO 2 are in TASI data, (3) that the emission peak at B6 (8.62μm), the slope at both side of B6 and the left side of B14 and B17 have positive correlation with SiO 2 content, (4)and that this method is very precise to extract high SiO 2 belts in study area, including granite area.
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