Fluid‐filled volumes in geological systems can change the local stress field in the host rock and may induce brittle deformation as well as crack propagation. Although the mechanisms relating fluid pressure perturbations and seismicity have been widely studied, the fluid‐solid interaction inside the crack of a host rock is still not well understood. An analog experimental model of fluid intrusion in cracks between planar layers has been developed to study stress conditions at the margins and tips. A combined high‐speed shadowgraph and a photoelasticity imaging system is used to visualize the fluid dynamics and induced stresses on the solid matrix. Cavitation, as well as bubble growth and collapse, occurs along the sawtooth crack margins, which produces a highly localized stress concentration to initiate new subcrack systems. The presence of the bubbles at the crack tip during fluid pressure perturbation can enhance crack propagation.

中文翻译：

---

几何形状和流体粘度对充填裂纹动力学的影响：模拟实验观察的启示

地质系统中充满流体的体积会改变母岩中的局部应力场，并可能引起脆性变形以及裂纹扩展。尽管已经广泛研究了与流体压力扰动和地震活动有关的机理，但是对于母岩裂缝内部的流体-固体相互作用仍然知之甚少。为了研究边缘和尖端的应力条件，已经开发出了一种模拟流体侵入平面层之间的裂缝的实验模型。结合了高速阴影图和光弹性成像系统，可以可视化固体基质上的流体动力学和诱导应力。气蚀以及气泡的生长和破裂沿着锯齿形的裂缝边缘发生，这会产生高度局部的应力集中，从而启动新的次裂缝系统。