Fracability evaluation is the basis of reservoir fracturing and fracturing zone optimization. The tight sandstone reservoir is characterized by low porosity and low permeability, which requires hydraulic fracturing to improve industrial productivity. In this study, a systematic model was proposed for the fracability evaluation of tight sandstone reservoirs. The rock mechanics tests and sonic tests demonstrated that tight sandstone reservoir is characterized by high brittleness, high fracture toughness, and weak development of natural fractures. Numerical simulation was used to analyze the change of reservoir parameters during hydraulic fracturing and the influence of in situ stress on fracture propagation. The results showed that when the horizontal stress anisotropy coefficient is small, natural fractures may lead hydraulic fractures to change direction, and complex fracture networks are easily formed in the reservoir. The horizontal stress anisotropy coefficient ranges from 0.23 to 0.52, and it is easy to produce fracture networks in the reservoir. A new fracability evaluation model was established based on the analytic hierarchy process (AHP). The fracability of tight sandstone reservoir is characterized by the fracability index (FI) and is divided into three levels. Based on the model, this study carried out fracability evaluation and fracturing zone optimization in the study area, and the microseismic monitoring results verified the accuracy of the model.

中文翻译：

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致密砂岩储层压裂性评价方法及影响因素

压裂性评价是储层压裂和压裂带优化的基础。致密砂岩储层具有低孔低渗特点，需要通过水力压裂提高工业产能。本研究提出了致​​密砂岩储层可压裂性评价的系统模型。岩石力学试验和声波试验表明，致密砂岩储层具有脆性大、断裂韧性高、天然裂缝发育弱的特点。通过数值模拟分析了水力压裂过程中储层参数的变化以及地应力对裂缝扩展的影响。结果表明，当水平应力各向异性系数较小时，天然裂缝可能导致水力裂缝改变方向，储层内容易形成复杂的裂缝网络。水平应力各向异性系数范围为0.23～0.52，储层内容易产生裂缝网络。基于层次分析法（AHP）建立了一种新的可压裂性评价模型。致密砂岩储层的可压裂性以可压裂性指数（FI）为特征，分为三个等级。本研究基于该模型在研究区开展可压裂性评价和压裂带优化，微地震监测结果验证了模型的准确性。并且在储层中容易产生裂缝网络。基于层次分析法（AHP）建立了一种新的可压裂性评价模型。致密砂岩储层的可压裂性以可压裂性指数（FI）为特征，分为三个等级。本研究基于该模型在研究区开展可压裂性评价和压裂带优化，微地震监测结果验证了模型的准确性。并且在储层中容易产生裂缝网络。基于层次分析法（AHP）建立了一种新的可压裂性评价模型。致密砂岩储层的可压裂性以可压裂性指数（FI）为特征，分为三个等级。本研究基于该模型在研究区开展可压裂性评价和压裂带优化，微地震监测结果验证了模型的准确性。