Abstract Investigation of oil fingerprints heterogeneities in different wells across the reservoir is a critical effort in various disciplines of geochemical studies. Exploring new, trustworthy, and straightforward techniques is an ongoing and interesting subject in the oil industry. In this paper, a novel procedure for oil fingerprints comparison by employing the structural characteristics of asphaltenes is suggested. For the first time, the modified version of the moving window correlation coefficient is proposed to resolve the drawbacks of the standard procedure and then implementing for comparison of oil fingerprints. This procedure is based on peak ratios calculated from the second derivative FTIR spectra of asphaltene samples. The results of this technique are summarized in a matrix with green, red and yellow cells based on the calculated values of the minimum correlation coefficient in all moving windows (MMWR) and the average of correlation coefficients in all moving windows (AMWR) regarding defined thresholds to better visualization of fingerprint similarity or dissimilarity between studied samples. The oil fingerprint similarities in the two case studies from the Dezful Embayment of southwest Iran were investigated to demonstrate the usefulness of this technique. Ten samples from different wells in the Qale Nar oil field and eight samples from the Shadegan oil field were studied. Results showed that crude oils in the Asmari reservoir from the Qale Nar field have a similar fingerprint and are homogenous. But crude oils in the Asmari reservoir from the Shadegan field involves several zones based on oil fingerprints similarity. Whole oil gas chromatography (WOGC) was performed for checking purposes. The proposed method based on FTIR spectra of asphaltene samples and their comparison with the modified moving window correlation coefficient can be regarded as a novel, reliable, and straightforward technique for oil fingerprint similarity assessment.

中文翻译：

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基于沥青质 FTIR 光谱的新技术评估油指纹相似性：修正移动窗口相关系数技术

摘要 油藏不同井中油指纹异质性的调查是地球化学研究各个学科的关键工作。探索新的、值得信赖的和直接的技术是石油行业中一个持续且有趣的主题。在本文中，提出了一种利用沥青质的结构特征进行油指纹比较的新方法。首次提出了移动窗口相关系数的修正版本，解决了标准程序的不足，并实现了油指纹比对。该程序基于从沥青质样品的二阶导数 FTIR 光谱计算的峰值比。该技术的结果总结在一个带有绿色的矩阵中，红色和黄色单元格基于所有移动窗口中的最小相关系数 (MMWR) 和所有移动窗口中的相关系数平均值 (AMWR) 的计算值关于定义的阈值，以更好地可视化研究样本之间的指纹相似性或不相似性。研究了伊朗西南部 Dezful Embayment 的两个案例研究中的石油指纹相似性，以证明该技术的实用性。研究了来自 Qale Nar 油田不同井的 10 个样品和来自 Shadegan 油田的 8 个样品。结果表明，来自 Qale Nar 油田的 Asmari 油藏中的原油具有相似的指纹并且是均质的。但是来自 Shadegan 油田的 Asmari 油藏中的原油涉及基于油指纹相似性的几个区域。进行全油气相色谱 (WOGC) 以进行检查。基于沥青质样品的 FTIR 光谱及其与修正的移动窗口相关系数的比较所提出的方法可以被视为一种新颖、可靠且直接的油指纹相似性评估技术。