图  1  非常规储层概念图

a—裂缝型储层概念图；b—缝洞型储层概念图

Figure  1.  Conceptual diagrams of unconventional reservoirs

(a) Conceptual diagram of a fractured reservoir; (b) Conceptual diagram of a fractured-vuggy reservoir

图  2  Biot系数与孔隙度关系曲线图（岩石骨架泊松比$ {\nu }_{s} $=0.2）

$ \eta $—裂缝纵横比

Figure  2.  Biot coefficient versus porosity plot (matrix Poisson's ratio $ {\nu }_{s} $ = 0.2)

$ \eta $—fracture aspect ratio

图  3  Biot系数与孔隙中溶洞占比关系曲线图 ($ {\nu }_{s} $=0.2、$ \eta $=50)

n—孔隙度

Figure  3.  Biot coefficient versus percentage of cavities in pores plot ($ {\nu }_{s} $ = 0.2、$ \eta $ = 50)

n—porosity

图  4  平面圆形裂缝扩展示意图

$ {\sigma }_{\text{f}} $—均匀拉应力；c—短轴长度；d—长轴长度

Figure  4.  Schematic of circular crack propagation in a plane

$ {\sigma }_{\text{f}} $—uniform tensile stress; c—minor axis length; d—major axis length

图  5  考虑和未考虑Biot系数水平主应力对比图

Figure  5.  Comparison of horizontal principal stresses with and without the Biot coefficient