压力作用下石英砂岩的热红外光谱变化与敏感响应波段

在实验室对石英砂岩进行单轴压缩加载,利用红外光谱辐射计(观测波段8～14μm)对加载过程中试样的红外光谱辐射变化特征进行观测,研究岩石红外辐射对应力响应的敏感波段。实验结果显示,当岩石被加载时,红外光谱随之发生变化,但不同波段变化特征不同,在8.0～11.5μm范围(尤其在8.6～9.1μm)石英砂岩的红外光谱辐射强度随载荷增加而增加,二者间近似呈两次曲线关系,且光谱辐射强度的"信噪比"较高;在其它波段光谱辐射强度与载荷的相关性差且"信噪比"较低。由此表明,8.0～11.5μm是石英砂岩红外辐射对应力响应的敏感波段,也是岩石应力与灾变红外遥感监测的优势波段,而最佳监测波段是8.6～9.1μm。

Thermal infrared spectral variation and sensitive waveband of quartzy sandstone under pressure

In the present paper the thermal infrared spectral variation of quartz sandstone under uniaxial compression was detected by a spectroradiometer to study the sensitively responding waveband of infrared radiation excited by the pressure. The experimental result shows that the infrared spectrum varies with the load, and the variation feature is different in different wavebands. The infrared radiation intensity increases with the increase in the load within the waveband 8.0-11.5 microm (specially in 8.6-9.1 microm), and there is a quadratic correlation between them, meanwhile the signal-to-noise ratio of spectrum radiation is also higher in the waveband. But in other wavebands the correlation is worse and the signal-to-noise is also lower. This indicates that the waveband 8.0-11.5 microm is the sensitive waveband of infrared radiation to the pressure, and it is also the superior waveband for infrared remote sensing monitoring the stress and catastrophe of rock. The optimum waveband is 8.6-9.1 microm.