Fracture spacing (s) distribution and its dependence on bed thickness (t) are investigated for opening-mode joints in sandstone interlayered with shale in the Sainte-Anne des Monts area (the Gaspé Peninsula), Quebec, Canada. The s values of cross joints, which extend across intervals between long parallel systematic joints and abut these joints at about 90° angles, are consistently larger than those of systematic joints by a mean factor of 1.81. The s-t relationship follows a power law: s = mt^1-1/k, where m equals half the ratio of layer tensile strength to interface shear stress, and k is the Weibull modulus. The m value is significantly larger for cross joints than systematic joints, indicating that the interfacial shear stress was direction-dependent during the deformation. The Weibull modulus of sandstone was larger during the formation of systematic joints than that of cross joints by a factor of ~1.2, indicating that the number and size of flaws in a unit of volume of the sandstone increased during progressive deformation. Furthermore, the compilation of s-t data from the literature yields: m = 2.53 ± 2.12 and k = 3.09 ± 1.24 for sandstones, and m = 3.53 ± 3.11 and k = 3.54 ± 1.33 for carbonates. The analysis also raises doubt about the existence of real joint saturation in sedimentary rocks.

在加拿大魁北克省 Sainte-Anne des Monts 地区（加斯佩半岛）与页岩夹层的砂岩中，研究了裂缝间距 (s) 分布及其对地层厚度 (t) 的依赖性。交叉接头的 s 值跨越长平行系统接头之间的间隔延伸并以大约 90°角邻接这些接头，始终比系统接头的 s 值大 1.81 的平均因子。st 关系遵循幂律：s = mt ^1-1/k，其中 m 等于层拉伸强度与界面剪切应力之比的一半，k 是威布尔模量。交叉接头的 m 值明显大于系统接头，表明界面剪切应力在变形过程中与方向有关。系统节理形成过程中砂岩的威布尔模量比交叉节理大约 1.2 倍，表明在渐进变形过程中，单位体积砂岩中的缺陷数量和尺寸增加。此外，从文献中汇编 st 数据得出：砂岩的 m = 2.53 ± 2.12 和 k = 3.09 ± 1.24，碳酸盐的 m = 3.53 ± 3.11 和 k = 3.54 ± 1.33。该分析还对沉积岩中是否存在真正的联合饱和提出了质疑。