硬脆性泥页岩水化稳定性研究

STUDY ON STABILITY OF BRITTLE SHALE HYDRATION

文章在分析泥页岩水化失稳基本结构的基础上,抽象出硬脆性泥页岩的物理模型,然后依据抽象出的物理模型,考虑钻井液滤液与页岩之间可能进行的各种物理化学反应,综合各种运移驱动力对滤液各组分运移的影响,以多孔介质传导(能量与物质)、吸附与扩散(水分子和水化离子)、双电层电场与电斥力为依据,建立起泥浆滤液在裂缝性泥页岩地层中的渗透运移规律及由此产生的水化应力和造成的地层强度变化的规律,最后落脚到应力、应变张量和破坏强度准则,形成了泥页岩水化稳定性的裂缝—孔隙双重介质分析模型系统。

Based on the analysis of basic structure for shale hydration stability loss, the physical model of brittle shale is abstracted. Then, according to the abstracted physical model, considering the different physical and chemical interaction between mud filtrate and shale, integrating the influence of different migration driving powers on migration of different filtrate components, and according to the transport of energy and material for porous mediums, the absorption and diffuse of water molecule and hydration ions, and the electric field and repulsion of electric double layer, the percolation and migration law of mud filtrate in fractured shale formations and the changing law of the hydrated stress and the formation strength can be found. Then, the criteria of stress, strain tensor and destroy strength are discussed, and the model system of fracture-pore dual mediums is developed to analyze the stability of shale hydration.