Modeling of fracturing, flow and geomechanics for analysis and optimization of shale gas/oil resources

页岩气正在迅速取代致密气，成为非常规天然气生产的主要来源。所使用的增产和开采技术类似于致密气，并采用了涉及多裂缝水平井的新现场技术。然而，在涉及的物理机制和所需的建模方法方面存在很大差异，主要与页岩地层的地质力学有关。 在商业上可行的页岩层通常是天然裂缝，裂缝系统渗透率和孔隙度在刺激和生产过程中随着应力的变化而变化。这导致了水力压裂过程中的非常规行为，以及随后的生产。严格结合地质力学的模型目前还不存在。这项拟议的研究将提供对这些现象的新理解，并开发严格的技术来模拟它们。该模型将页岩中裂隙介质的地质力学与双重孔隙、页岩中的对流和扩散流以及水力压裂完全耦合起来。此外，这项研究将包括与迅速发展的微震监测学科相结合，以增进对微震事件与裂缝尺寸之间关系的理解。 预计该研究将对页岩井动态分析和未来开发优化产生重要影响。开发的模拟工具将允许检查不同页岩业务的异同以及控制其生产率的参数，从而为行业提供做出更好的资源开发决策的手段。

Shale gas is rapidly replacing tight gas as a main source of unconventional gas production. The stimulation and production techniques used are similar to tight gas, and employ new field techniques involving multiply fractured horizontal wells. However, there are large differences in physical mechanisms involved and the resulting approach needed to model them, primarily related to geomechanics of the shale formations. Commercially viable shale plays are often naturally fractured and the fracture system permeability and porosity varies with changing stress during stimulation as well as production. This leads to unconventional behavior during hydraulic fracturing, as well as subsequent production. Models incorporating geomechanics rigorously currently do not exist. The proposed research will provide new understanding of these phenomena and develop rigorous techniques to model them. The models will fully couple the fractured-media geomechanics of shales with dual porosity, convection and diffusion flow in shales, and hydraulic fracturing. In addition, the research will include integration with the rapidly developing discipline of microseismic monitoring, in order to improve the understanding of the relationship of microsismic events to fracture dimensions. The research is expected to have significant impact on both the analysis of the shale well performance and the optimization of the future development. The simulation tools developed will allow examining the similarities and differences of different shale plays and the parameters controlling their productivity, thereby providing industry with means to make better resource development decisions.