热红外高光谱遥感回归分析定量反演石英含量

Thermal Hyperspectral Remote Rensing for the Quantitative Inversion of Quartz Content by Regression Analysis

热液矿床是重要的矿床类型,包含金矿、铜矿、锡矿、铀矿、钨矿、铅锌矿等重要矿床。在多数情况下,热液活动造成其与围岩石英含量的差异。目前遥感技术仅能提取SiO_2含量(或相对含量)及其分布范围,难以精确反映石英含量的差异信息。通过分析JHU波谱库中不同矿物的光谱曲线以及其他多种含石英岩石和不含石英岩石的光谱曲线,区分了SiO_2光谱特征谱段和石英光谱特征谱段。使用热红外地面光谱仪102f实测样品光谱,通过线性回归方程统计出石英含量的计算公式。最后,通过热红外成像光谱仪(thermal airborne hyperspectral imager,TASI)提取研究区石英含量来验证公式的正确性,并得到野外验证。得出结果:8.6μm处的发射峰是8~11.5μm范围内石英唯一明显的光谱特征,其发射峰的凸显程度与石英含量呈正相关关系。

Hydrothermal deposit is an important type of deposits,and the minerals include gold,copper,tin,uranium,tungsten,lead and zinc and other important deposits. In most cases,hydrothermal activity results in difference quartz content between the local and the surrounding rock. At present,remote sensing technology can only extract SiO_2 content（ or relative content） or its distribution range,and it is difficult to accurately reflect the information of different quartz content. By analyzing the spectral curves of different minerals in the JHU spectra library and the other spectral curves of quartz rock and quartz-free rocks,the characteristic spectrum of quartz was distinguished from that of SiO_2. The spectrum of the sample was measured by the thermal infrared spectrometer102 f,and the calculation formula of the quartz content was calculated by the linear regression equation. Finally,the correctness of the formula was verified by the quartz content of the study area extracted by TASI data and it was verified by field work. The result shows that the emission peak at 8. 6 μm is the only obvious spectral characteristic of quartz in the spectrum range of 8 ~ 11. 5 μm,and its emission peak has a positive correlation with the quartz content.