致密薄互层水力压裂裂缝垂面扩展施工因素数值模拟

中国具有丰富的致密油气藏储量，必将成为中国接替的油气资源。致密油藏开发主要依靠水力压裂技术，对于致密薄互层，施工因素作为可控因素，对于现场施工具有重要意义。因此，本文研究针对鄂尔多斯盆地致密储层，低孔低渗、储层厚度薄等特点，以该地区L井F12地层为例，采用Abaqus有限元软件进行了模拟计算，研究了施工过程中的排量以及压裂液黏度对裂缝垂面扩展规律的影响，并且根据实际情况对模型进行验证，确定了模型和模拟方法的准确性。研究结果表明：压裂液的排量对于裂缝的扩展具有重大影响，排量越大，裂缝的扩展速度越快，裂缝的缝高和缝宽越大；压裂液黏度对裂缝的扩展行为影响微乎其微。并进一步分析发现，针对致密薄互层，仅仅只改变压裂液排量和黏度并不能将裂缝控制在储层内，采用变排量控缝高技术辅以其他控缝高手段能够更好地将裂缝控制在储层内，为现场压裂施工提供了基础。

Numerical simulation study on the construction factors of vertical fracture propagation in tight and thin interlayer hydraulic fracturing

Our country has abundant reserves of tight oil and gas reservoirs, which will surely become the oil and gas resources that my country will take over. The development of tight oil reservoirs mainly relies on hydraulic fracturing technology. For tight and thin interbeds, the construction factor is a controllable factor, which is of great significance for on-site construction. Therefore, in view of the characteristics of tight reservoirs in Yanchang, low porosity, low permeability, and thin reservoir thickness, taking the F12 formation of Well L in this area as an example, the Abaqus finite element software was used to simulate and calculate, and the drainage during the construction process was studied. The influence of the amount of fracturing fluid and the viscosity of fracturing fluid on the fracture vertical plane propagation law, and the model is verified according to the actual situation, and the accuracy of the model and the simulation method is confirmed. The research results show that the displacement of fracturing fluid has a significant impact on the expansion of fractures. The greater the displacement, the faster the expansion of cracks, and the greater the height and width of fractures. The viscosity of fracturing fluid has an influence on the expansion behavior of fractures. Minimal. And further analysis found that for tight and thin interbeds, only changing the displacement and viscosity of the fracturing fluid cannot control the fractures in the reservoir. Fractures are controlled within the reservoir, providing a foundation for on-site fracturing construction.