笔石组成与结构的微区分析

THE COMPOSITION AND STRUCTURE OF GRAPTOLITE ── A MICRO-AREA ANALYSIS

采用显微傅立叶红外光谱（Micro－FT－IR）和装有液体金属离子枪的高分辨飞行时间二次离子质谱仪（TOF－SIMS）首次研究了笔石的化学组成与结构。Micro－FT－IR谱图在1680～1740cm－1和1000～1320cm－1范围内吸收强度高，而1600cm－1处吸收强度低．表明笔石是由含N、O等杂质原子基团的高分子聚合物组成，且该笔石热演化程度不高；TOF－SIMS谱图表明，笔石的二次离子峰主要集中在较低质量数处，在高质量数峰强度低，且M／Z43，105，135等峰强度高，亦证实笔石的上述组成特点。研究结果表明Micro－FT－IR和TOF－SIMS技术是煤及源岩显微组分微区成分分析的有力工具。

The paper is concerned with the composition and structure of graptolite by using reflectance Fourier transformation infrared microspectroscopy (Micro-FT-IR) and high-resolutiontime-of-flight secondary ion mass spectroscopy (TOF-SIMS) equipped with a liquid metal ion gun.Micro-FT-IR data show that the absorbance of graptolite is high at 1 680~1 740 cm-1 and 1 000~1 320cm-1 but low at 1 600 cm-1, indicating that graptolite consists of macromolecular polymerscontaining abundant hetero atomic radicals of oxygen, nitrogen, etc., and the degree of their thermal evolution is not so high. TOF-SIMS analysis shows that the ions of graptolite are mainly in thelow-mass range, the intensities of ions in the high mass range are low, and the peaks for M/Z 43,105, 135, etc. are relatively high, also confirming the above-mentioned compositional features ofgraptolite. The study shows that the Micro-FT-IR and TOF-SIMS techniques are powerful meansfor the compositional microanalysis of coal and source rock macerals.