Geomechanical modelling and simulation are introduced to accurately determine the combined effects of hydrocarbon production and changes in rock properties due to geomechanical effects. The reservoir geomechanical model is concerned with stress-related issues and rock failure in compression, shear, and tension induced by reservoir pore pressure changes due to reservoir depletion. In this paper, a rock mechanical model is constructed in geomechanical mode, and reservoir geomechanics simulations are run for a carbonate gas reservoir. The study begins with assessment of the data, construction of 1D rock mechanical models along the well trajectory, the generation of a 3D mechanical earth model, and running a 4D geomechanical simulation using a two-way coupling simulation method, followed by results analysis. A dual porosity/permeability model is coupled with a 3D geomechanical model, and iterative two-way coupling simulation is performed to understand the changes in effective stress dynamics with the decrease in reservoir pressure due to production, and therefore to identify the changes in dual-continuum media conductivity to fluid flow and field ultimate recovery. The results of analysis show an observed effect on reservoir flow behaviour of a 4% decrease in gas ultimate recovery and considerable changes in matrix contribution and fracture properties, with the geomechanical effects on the matrix visibly decreasing the gas production potential, and the effect on the natural fracture contribution is limited on gas inflow. Generally, this could be due to slip flow of gas at the media walls of micro-extension fractures, and the flow contribution and fracture conductivity is quite sufficient for the volume that the matrixes feed the fractures. Also, the geomechanical simulation results show the stability of existing faults, emphasizing that the loading on the fault is too low to induce fault slip to create fracturing, and enhanced permeability provides efficient conduit for reservoir fluid flow in reservoirs characterized by natural fractures.

引入了地质力学建模和模拟，以准确确定油气生产和岩石力学特性引起的岩石性质变化的综合影响。油藏地质力学模型涉及与应力有关的问题，以及由于油藏枯竭而引起的油藏孔隙压力变化而引起的压缩，剪切和张应力中的岩石破坏。在本文中，以地质力学模式构造了岩石力学模型，并对碳酸盐岩气藏进行了储层地质力学模拟。该研究首先进行数据评估，沿井眼轨迹构建一维岩石力学模型，生成3D机械地球模型，以及使用双向耦合模拟方法进行4D地质力学模拟，然后进行结果分析。将双重孔隙率/渗透率模型与3D地质力学模型耦合，并进行迭代的双向耦合仿真，以了解有效应力动力学随生产引起的储层压力降低而发生的变化，从而识别出双重孔隙/渗透率的变化。连续介质电导率对流体流动和油田最终采收率的影响。分析结果表明，观察到的对储层流动行为的影响为：气体最终采收率降低了4％，基质贡献和裂缝特性发生了显着变化，对基质的岩土力学影响明显降低了天然气的生产潜力，而对基质的影响则减小了。天然裂缝的贡献受天然气流入的限制。通常，这可能是由于微延伸裂缝介质壁处的气体滑流引起的，对于基质填充裂缝的体积，流量贡献和裂缝导流能力已经足够。此外，地质力学模拟结果显示了现有断层的稳定性，强调了断层上的载荷太低而不会引起断层滑动而产生裂缝，而增强的渗透性为以天然裂缝为特征的储层中的流体流动提供了有效的管道。