Fracture process in rocks and earthquakes

由于其易碎的性质，岩石在所有长度尺度上断裂：从颗粒中的微裂纹（或沿着晶界），尺寸小于一毫米，到沿着沿着断层的巨大地震破裂，这些断层定义了数百公里长的构造边界。 断裂和断裂过程在确定岩石的本构响应和与灾难性岩石断层相关的地质灾害特征方面起着重要作用。 因此，对岩石断裂的研究将有助于我们了解和减轻地质灾害（地震、滑坡等），解决矿山中的安全问题（例如，斜坡不稳定、岩爆），并改善地下水和放射性废物的管理。 从历史上看，理解岩石断裂的研究工作主要集中在实验室静态断裂和地震观测和地震数值模拟上。 为了了解灾难性破坏中岩石的动力特性，需要专门设计的实验。 继申请人在实验室地震实验和自发破裂实验方面的早期工作之后，他将研究二维和三维地震断层的特征。 申请人还将系统地测量岩石的动态断裂韧性和岩石的动态拉伸强度，这是量化动态岩石破坏的两个重要参数。 这项研究将使用多伦多大学的岩石动态断裂设施（CFI-Young领导PI）、高速摄像机和气枪合作进行。 此外，申请人正在使用多伦多大学的启动奖建造一个气枪，并正在准备CFI/LOF提案，要求使用超高速摄像机。

Due to its brittle nature, rock breaks at all length scales: from micro-cracks in grains (or along grain boundaries) with sizes smaller than a millimeter to huge earthquake ruptures along faults that define tectonic boundaries with lengths of hundreds of kilometers. Fractures and fracture processes play an important role in the determination of the constitutive response of rocks and the characteristics of geological hazards that are associated with catastrophic rock faults. Thus, the investigation of fractures in rocks will help us understand and mitigate geological hazards (seismic, landslide, etc.), address safety issues in mines (e.g., slope instability, rockbursts), and improve the management of groundwater and radioactive waste. Historically, research efforts to understand rock fractures have been focused mainly on laboratory static fractures and on the seismic observations and numerical simulations of earthquakes. In order to understand the dynamic properties of rocks involved in catastrophic failures, specially designed experiments are necessary. Following the applicant's earlier work in the laboratory earthquake experiments and spontaneous fracture experiments, he will study the characteristics of earthquake faulting in both two- and three-dimensions. The applicant will also systematically measure the dynamic fracture toughness of rocks and the dynamic tensile strength of rocks, two important parameters in the quantification of dynamic rock failure. The research will be carried out using the Rock Dynamic Fracture Facility (CFI-Young lead PI) at the University of Toronto, the high speed camera, and the gas gun through collaboration. In addition, the applicant is building a gas gun using the start-up award from the University of Toronto and is preparing a CFI/LOF proposal to request an ultra high speed camera.