|
|
|
|
|
|
| FTIR Spectroscopic Characterization of Crude Oil Maturity and Salinity Regulatory Mechanisms |
| ZHANG Han-jing1, WANG Fei1, WANG Tao1, LI Jing-song1, LI Zhen1, WANG Juan1, WANG Jin-wei1, HAO Peng-ling1, LI Su-mei2, TIAN Miao1, ZHANG Yu1, LIU Huan1 |
1. China Oilfield Services Limited, Production Optimization, Tianjin 300450, China
2. College of Geosciences, China University of Petroleum, Beijing 102249, China
|
|
|
|
|
Abstract To achieve breakthroughs in the rapid evaluation of crude oil maturity, this study innovatively established a maturity discrimination model based on Fourier Transform Infrared Spectroscopy (FTIR). The crude oil from the source rock series of Es3 and Es4 in the Dongying sag of the Jiyang depression is used as the research object. By analyzing the maturity parameters of biomarkers such as sterane (C29αββ/(ααα+αββ), C2920S/(20S+20R) ) and terpane (Ts/(Ts+Tm)), the intrinsic correlation between FTIR and thermal evolution degree of crude oil was established. In this study, Origin2025 software was used for baseline correction and Gaussian-Lorentz mixture model (Voigt function) deconvolution technology to analyze the infrared spectral characteristics. The relationship between the characteristic peak area ratio (A∑CH2/A∑CH3) of the aliphatic hydrocarbon vibration region (2 800～3 000 cm-1) and maturity was revealed for the first time. The ratio decreases from 4. 33 in the low maturity stage (C29αββ/(ααα+αββ)=0.30) to 1.03 in the high maturity stage (C29αββ/(ααα+αββ)=0.60). Combined with molecular dynamics analysis, it is found that the β-cleavage of long-chain alkanes is the main mechanism for the decrease of the relative abundance of the —CH2— group with the increase of maturity. The long-chain alkane structure in the low-mature oil is intact, while the mature oil produces significant short-chain alkane chaining due to thermal cracking. Under the same maturity conditions, the A∑CH2/A∑CH3 value of crude oil in a high-salinity environment ( gammacerane/ C30 hopane=0.81) was significantly increased by 23.5% compared with that in a freshwater environment. Molecular simulation shows that salinity can effectively delay the decay process of the —CH2— group in long-chain alkanes by inhibiting sulfide cracking reaction, which provides new experimental evidence for the influence of paleosalinity on the evolution path of organic matter. Compared to traditional gas chromatography-mass spectrometry (GC-MS) technology, this method achieves three major technological innovations. (1) Nondestructive testing characteristics. Only a small amount of sample (<50 μL) is required to complete the analysis, avoiding sample loss caused by complex pretreatment. (2) The analysis efficiency jumped, and the single-sample detection time was compressed to 5 minutes. (3) The breakthrough of in-situ applicability can be directly applied to in-situ maturity evaluation of unconventional reservoirs such as shale oil and tight oil, and successfully overcomes the dependence of conventional methods on movable hydrocarbon content. The research results provide a molecular-scale tool for evaluating unconventional resources, such as shale oil, which has both theoretical and engineering application value.
|
|
Received: 2025-04-30
Accepted: 2025-08-20
|
|
|
|
[1] Kvalheim O M, Christy A A, Telnæs N, et al. Geochimica et Cosmochimica Acta, 1987, 51(7): 1883.
[2] Li M W, Fowler M G, Obermajer M, et al. Organic Geochemistry, 1999, 30(9): 1039.
[3] Pironon J, Sawatzki J, Dubessy J. Geochimica et Cosmochimica Acta, 1991, 55(12): 3885.
[4] Pironon J, Thiery R, Ayt Ougougdal M, et al. Geofluids, 2001, 1(1): 2.
[5] Cheng P，Liu B T，Tian H，et al. Organic Geochemistry，2021，159：104273.
[6] LIU Bo-tong, CHENG Peng, GAI Hai-feng, et al(刘博通, 程 鹏, 盖海峰, 等). Oil & Gas Geology(石油与天然气地质), 2023, 44(1): 150.
[7] LI Jing-yan, CHU Xiao-li, TIAN Song-bai(李敬岩, 褚小立, 田松柏). Acta Petrolei Sinica(Petroleum Processing Section)[石油学报(石油加工)], 2012, 28(3): 476.
[8] Zhang H J, Li S M. Fuel, 2023, 333(Part 2): 126408.
[9] Li S, Pang X, Jin Z, et al. Marine & Petroleum Geology, 2010, 27680(7): 1411.
[10] Pironon J, Barres O. Geochimica et Cosmochimica Acta, 1990, 54: 509.
[11] PING Yuan(平 原). Marine Origin Petraleum Geology(海相油气地质), 1999, 728(1): 47.
|
| [1] |
MA Dian-xu, CAI Yan, LI Xiao-pan, CHENG Li-jun, YANG Hai-tao, SHAN Chang-ji, DU Guo-fang. Comprehensive Identification and In-Depth Analysis of Zhaotong Apples Facilitated by Multidimensional Fourier Transform Infrared Spectroscopy Integrated With Two Neural Network Models[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2025, 45(06): 1543-1550. |
| [2] |
GAO Fei1, 2, LIN Wan1, JIA Zhe1, BAI Qi-hui1, LIU Jing1, WANG Yi-fan1, LI Wei-ying3. Spectroscopic Study on the Evolution of Coal Molecular Structure During CO2 Storage[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2025, 45(06): 1791-1800. |
| [3] |
WANG Hong-en, FENG Guo-hong*, XU Hua-dong, ZHANG Run-ze. Identification of Blueberry Ripeness Based on Visible-Near Infrared
Spectroscopy and Deep Forest[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2024, 44(11): 3280-3286. |
| [4] |
HUANG Ya-hao1, XUE Yi-fan1, WEN Zhi-gang1, CHEN Jun-lin2, QIAO Zhan-feng3, 4*, LIU Yi-cheng1. Quantitative Fourier Infrared Spectroscopy Model of a Single CO2 System Under High Temperature and Pressure and Its Application to Natural
Inclusions[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2024, 44(08): 2256-2261. |
| [5] |
YUAN Wei-dong1, 2, JU Hao2, JIANG Hong-zhe1, 2, LI Xing-peng2, ZHOU Hong-ping1, 2*, SUN Meng-meng1, 2. Classification of Different Maturity Stages of Camellia Oleifera Fruit
Using Hyperspectral Imaging Technique[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(11): 3419-3426. |
| [6] |
HU Bin1, 2, WANG Pei-fang1, 2*, ZHANG Nan-nan3, SHI Yue4, BAO Tian-li1, 2, JIN Qiu-tong1, 2. Effect of pH on Interaction Between Dissolved Organic Matter and Copper: Based on Spectral Features[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2023, 43(05): 1628-1635. |
| [7] |
LIU Qiang1, LIU Shao-bo1, 2, LU Xue-song1, 2*, FAN Jun-jia1, 2, TIAN Hua1, 2, MA Xing-zhi1, 2, GUI Li-li1, 2. Research Progress in the Application of Raman Spectroscopy in Petroleum Geology[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(09): 2679-2688. |
| [8] |
LI Huan-tong1, 2, ZHU Zhi-rong1, 2, QIAO Jun-wei1, 2, LI Ning3, YAO Zheng3, HAN Wei1, 2. Molecular Representations of Jurassic-Aged Vitrinite-Rich and
Inertinite-Rich Coals in Northern Shannxi Province by
FTIR, XPS and 13C NMR[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(08): 2624-2630. |
| [9] |
XUE Xin-xin, WANG Wen-bin, LUO Xue-hua, ZHANG Yong-fa, ZHAO Chun-mei. FTIR Spectroscopic Characterization of Material Composition in Leaf of Hevea Brasiliensis Seedlings Under Potassium and Magnesium Deficiency[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(01): 74-79. |
| [10] |
REN Shuang-zan1, WANG Jing-wei2, GAO Liang-liang2, ZHU Hong-mei1, WU Hao1, LIU Jing1, TANG Xiao-jun2*, WANG Bin2. A Novel Compensation Method of Gas Absorption Spectrum Based on Time-Sharing Scanning Spectra and Double Gas Cell Switching[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2021, 41(11): 3438-3443. |
| [11] |
ZHOU Jing1,2, ZHANG Qing-qing1,2, JIANG Jin-guo2, NIE Qian2, BAI Zhong-chen1, 2*. Study on the Rapid Identification of Flavonoids in Chestnut Rose (Rosa Roxburghii Tratt) by FTIR[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2021, 41(10): 3045-3050. |
| [12] |
YANG Sheng-hui, ZHENG Yong-jun*, LIU Xing-xing*, ZHANG Tian-gang, ZHANG Xiao-shuan, XU Li-ming. Cabernet Gernischt Maturity Determination Based on Near-Ground Multispectral Figures by Using UAVs[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2021, 41(10): 3220-3226. |
| [13] |
CHEN Nan1, 2, WANG Yue1, 4, WANG Bo-yu1, 3, XIA Yang1, 2, 4, LIU Tao1, 4*. Research on Numerical Model of Nano-FTIR System Based on COMSOL[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2021, 41(04): 1125-1130. |
| [14] |
ZHANG Xu1, ZHANG Tian-gang2, MU Wei-song1, FU Ze-tian2,3, ZHANG Xiao-shuan2,3*. Prediction of Soluble Solids Content for Wine Grapes During Maturing Based on Visible and Near-Infrared Spectroscopy[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2021, 41(01): 229-235. |
| [15] |
HUANG Yu-ping1, WANG De-zhen1, ZHOU Hai-yan1, YANG Yu-tu1, CHEN Kun-jie2*. Ripeness Assessment of Tomato Fruit by Optical Absorption and Scattering Coefficient Spectra[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2020, 40(11): 3556-3561. |
|
|
|
|
