沉积岩中残留有机质的拉曼光谱特征

对沉积岩中残留的无烟煤、固体沥青和石墨3种有机质的拉曼光谱进行了测定,结果表明三者的拉曼光谱均具有明显的特征,石墨的拉曼光谱峰强而锋利,其2个一级峰之间的距离最小且变化不大,说明其演化程度比较高,有的甚至达到了结晶石墨的程度;无烟煤的拉曼光谱一级峰的强度比较弱,半高宽值也比较大,二级峰不明显;固体沥青的拉曼光谱峰形与无烟煤相似,不过其峰的半高宽比较窄,二级峰也比无烟煤要明显得多.另外,除了变质程度比较高的石墨外,其他2种有机质2个一级峰之间的距离均随着样品深度的增大而变小.

Raman Spectrum of Residual Organic Matter from Sedimentary Rocks

The Raman spectra of anthracite, bitumen and graphite from sedimentary rocks have been determinated. Their Raman spectroscopic characteristics such as frequencies, bandwidths and features of two order Raman spectra can be used to estimate the structural order and the presence of structural defects in residual organic matter from sedimentary rocks. The graphite with high evolvement degree, has the strongest and sharpest Raman peaks,and the distance of two first order Raman peaks is the smallest with little changes. Although the Raman peaks of bitumen are stronger and sharper than the anthracites , their Raman spectroscopic characteristics are very similar. With the increase of the depth of sample occurance, the distance of two first order Raman peaks decreases obviously.