Integrated multiscale characterization of tight sandstone reservoirs in the Taiyuan Formation, Q area, Ordos Basin: implications for diagenetic-structural coupling and reservoir evaluation

作者：Xin Xu, Jianping Liu, Weigang Zhang, Xian‐Fang Li, Zhanrong Ma, Rong‐Bin Huang, Le Qu, Xinyu Zhong · 发表于：Petroleum Science and Technology · 年份：2025 · DOI：10.1080/10916466.2025.2517072 · 被引用次数：1 · 研究领域：Hydrocarbon exploration and reservoir analysis、Geological Studies and Exploration、Hydraulic Fracturing and Reservoir Analysis

Recent exploration breakthroughs in Taiyuan Formation in the Q area have confirmed economically viable gas production. To analyze the reservoir characteristics in depth, this study establishes a predictive reservoir evaluation framework by integrating multiscale sedimentological, diagenetic, and structural analyses using core, thin sections, scanning electron microscopy, mercury injection and nuclear magnetic resonance data. The results indicate: i) Taiyuan Formation mainly composed of lithic quartz sandstone, followed by quartz sandstone and lithic sandstone. The pore is mainly composed of intergranular, vuggy, microcrystalline pores, and microfractures. ii) The favorable reservoir has a mercury injection curve of Y1 type and a nuclear magnetic resonance T2 spectrum curve of H1 type. iii) The reservoirs are influenced by structure movements, sedimentary facies, and diagenesis. Gas wells are mainly located in high positions of the structure, while the structure movements have some impact on the formation of structural fractures. The favorable facies zones of the Taiyuan Formation are tidal channels and barrier sandbar microfacies, and diagenesis plays a decisive role in the later reconstruction of reservoirs. This work introduces an innovative "structure-sediment-diagenesis coupling" method to analyze reservoir, and the proposed reservoir evaluation criteria provide a rapid screening tool for sweet-spot identification in similar geological backgrounds.