论文详情
微地震事件的分布范围和密度与页岩气井的产量有较好的正相关关系,经济、高效地进行微地震事件的压前预测和压后评估,对压裂增产优化设计具有重要的指导意义。针对微地震监测技术成本高和施工受限的问题,基于渗流力学和岩石力学理论,结合天然裂缝张性和剪切破坏准则,建立了水力裂缝动态扩展过程中微地震事件模拟预测的流固耦合数学模型,给出了数值求解方法。采用涪陵页岩气示范区HF-X水平井的储层地质参数和施工参数,对页岩储层压裂过程中剪切和张性微地震事件的动态演化和展布进行数值模拟,模拟结果与实时监测的微地震数据吻合度高于80%。结果表明,该理论方法能够经济、高效和可靠地预测微地震事件的展布。
The distribution and density of microseismic events have a positive correlation with shale gas production.The effective pre-fracturing prediction and post-fracturing analysis of microseismic events is of great significance for the optimal design of fracturing stimulation.Considering the high cost and limited implementation conditions of microseismic monitoring,a fluid-solid coupling mathematical model was established based on the theories of fluid mechanics and rock mechanics,and the detailed numerical solution of the model was determined.The model was developed for the simulation of microseismic events during the dynamic expansion of hydraulic fractures.The shale reservoir was considered to be a continuous medium composed of a large number of natural fractures,and the tensional and shear failure criteria of natural fractures were also characterized.The dynamic evolution and distribution of microseismic events were simulated by using geological and hydraulic fracturing parameters of the HF-X horizontal well in the Fuling shale gas field.Based on statistical analyses,more than 80% of microseismic signals resided within the contour of calculated microseismic events.Therefore,the theoretical calculation method can predict microseismic events economically and efficiently.
国家自然科学青年基金(41204101)资助。