碳酸盐岩储层流体包裹体差分拉曼光谱的研究

拉曼微探针分析法对单个气液包裹体的化学成分和相态的无破坏性测量来说,目前几乎是唯一最好的方法.但是由于众多因素的影响,特别是主矿物具有较强荧光时,提高信噪比的问题急待解决.本工作对碳酸盐岩储层包裹体样品制成的薄片进行了显微观察、荧光测试及拉曼分析,并进行了空间上横向XY扫描、纵向上深度剖析(Z扫描)和冷热台上变温的流体包裹体筹分拉曼光谱测量方法的研究.结果表明,所得到的差谱揭示了包裹体更真实的光谱曲线,消除了主矿物对包裹体的干扰,以较高的信噪比显现出包裹体中流体(-170℃温度下的冰)位于位移波数3 098 cm-1附近的宽拉曼散射峰,明显的改善了信噪比.

The difference-Raman spectra of fluid inclusion of carbonate reservoir

In the present paper, the authors examined some inclusions of carbonate reservoir by microscopic confocal Raman spectral methods. The measurement temperature of sample was 18 degrees C, -40 degrees C, -80 degrees C and -170 degrees C, respectively. The experimental results show that the original experimental spectral curve of the inclusion was very similar to the original experimental spectral curve of pure main mineral (rock core). Because the size of some inclusions was relatively small or inclusions were hid den deeply in the sample, their Raman spectra signals were often buried in other signals (noises) which stem from main mineral. To overcome the above-mentioned difficulty we used the spectral subtraction method. In Raman spectral experimental process, X-Y scanning and depth profile (Z scanning) were finished around the inclusion. The final results show that spectral subtraction method allows the study of solid samples with high precision because some corrections can be made, if additive properties of spectral quantity are satisfied. Interfering spectral signal from main mineral can be removed, and the inclusion spectrum can be purified.