Abstract The chemical analysis of carbonaceous and organic materials in geological samples (i.e., rocks) is an important and necessary step of hydrocarbon resource development. Despite some significant advances in the last several decades, there still is a need for improved analytical techniques that deliver greater sensitivity and reliable information regarding source rock properties and characterisation. Infrared spectroscopy is a promising technique in terms of providing both qualitative and quantitative information on carbonaceous materials. However, the application of this method for routinely determining parameters relevant to the organic geochemistry of geological systems has not been widely accepted. Here, we compare infrared spectroscopy to standard methods for deriving the total organic carbon content, number of free/volatile hydrocarbons and the hydrocarbon generating potential in shale rocks. Two common methods for collecting infrared spectra, namely Attenuated Total Reflectance (ATR) and Diffuse Reflectance Infrared Fourier Transform (DRIFT) spectroscopy, were evaluated to determine which one is most suitable for shale characterisation. It was revealed that the carbonate overtone band is largely responsible for causing quantitative interferences and errors. Although DRIFT was more sensitive, it was found that the ATR method is less prone to spectral interferences caused by the carbonate overtone band. Irrespective, both methods yielded reasonable correlations against established analytical techniques providing that the C H absorption band was corrected for variations in the carbonate content.

中文翻译：

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使用中红外光谱分析页岩中的碳质材料

摘要 对地质样品（即岩石）中的碳质和有机物进行化学分析是油气资源开发的一个重要且必要的步骤。尽管在过去几十年中取得了一些重大进展，但仍然需要改进的分析技术，以提供有关烃源岩性质和特征的更高灵敏度和可靠信息。红外光谱在提供碳质材料的定性和定量信息方面是一种很有前途的技术。然而，该方法用于常规确定与地质系统有机地球化学相关的参数的应用尚未被广泛接受。在这里，我们将红外光谱与用于推导总有机碳含量的标准方法进行比较，页岩中游离/挥发性烃的数量和生烃潜力。评估了两种常用的红外光谱收集方法，即衰减全反射 (ATR) 和漫反射红外傅立叶变换 (DRIFT) 光谱，以确定哪一种最适合页岩表征。结果表明，碳酸盐泛音带是造成定量干扰和误差的主要原因。虽然 DRIFT 更灵敏，但发现 ATR 方法不太容易受到碳酸盐泛音带引起的光谱干扰。无论如何，如果 CH 吸收带根据碳酸盐含量的变化进行校正，两种方法都与已建立的分析技术产生了合理的相关性。