Investigating Earthquake Source Processes in the Laboratory

为了加深我们对地震这一自然现象的理解，并试图减少地震造成的灾难性破坏，人们一直在努力进行地震研究。然而，直接观测地震过程是不可能的，因为它们发生在沿着断层几公里到几百公里深处。来自俄克拉荷马州大学的研究人员开发了一个实验室，该实验室配备了在天然岩石样本上复制地震速度和偏移的工具。他们将与希伯来大学的一个实验室合作，该实验室模拟丙烯酸树脂的高速压裂，丙烯酸树脂与天然岩石不同，但可以帮助研究人员了解可能与天然岩石实验有关的情况。这些免费实验室实验的组合将帮助我们了解裂缝如何引起地震并辐射地震波。这些信息对于提高我们对地震危害的理解是很重要的，因为它将推进我们对强烈地面震动的了解。俄克拉荷马州大学的研究小组开发了一种装置，可以在实验性岩石断层上物理模拟大地震的速度和位移。该团队成功地再现了岩石弱化和能量消耗的著名地震特征。希伯来大学的研究小组开发了独特的高速实验工具，可以定量测量“实验室”地震破裂的极快机械演化。该项目将联合收割机结合两个实验系统的独特功能，以更好地了解地震破裂，包括详细描述岩石破裂，摩擦和地面震动的现实过程。深部地震过程的实验数据对于导出有用的模型、解释地震观测和评估地震危险性是必不可少的。这两个实验系统的先进特点将允许监测破裂沿着岩石断层在非常高的分辨率，这是不能实现的自然地震。预计这种破裂监测将提供实验，理论和地震概念之间的缺失环节，因此将大大提高地震破裂过程，地震能量平衡，断层弱化的物理学，以及滑动率，滑动震级和地震危险性的缩放的理解。

Major efforts have been devoted to earthquake research to further our understanding of this natural phenomenon and attempt to reduce its disastrous damage. However, it is not possible to directly observe earthquake processes, because they occur along faults at depths of a few to hundreds of kilometers. The researchers from Oklahoma University have developed an experimental laboratory with tools to duplicate earthquake speeds and offsets on samples of natural rocks. They will partner with a laboratory at Hebrew University that simulate high speed fracturing on acrylics, which are not the same as naturally occurring rocks but can help researchers see aspects of what is happening that could be related to the natural rock experiments. The combination of these sets of complimentary lab experiments will help us to understand how fractures that cause earthquakes and radiates seismic waves. This information is important to improving how we understand seismic hazards because it will advance what we know about strong ground shaking.The Oklahoma University team developed an apparatus that physically simulates the velocity and displacement of large earthquakes on experimental rock faults. This team succeeded in reproducing well-known earthquake features of rock weakening and energy consumption. The Hebrew University team has developed unique, high-speed experimental tools that quantitatively measure the extremely fast mechanical evolution of the rupture of a "laboratory" earthquake. The project will combine the unique capabilities of the two experimental systems for better understanding of earthquake rupture, including detailed description of realistic processes of rock fracturing, friction, and ground shaking. Experimental data on earthquake processes at depth are essential for the derivation of useful models, interpretation of seismic observations, and the evaluation of seismic hazard. The advanced features of the two experimental systems will allow monitoring of rupture along rock-faults at very high resolution, which cannot be achieved for natural earthquakes. It is anticipated that this rupture monitoring will provide the missing links between experiments, theory and seismic concepts, and therefore will significantly advance the understanding of earthquake rupture processes, earthquake energy balance, physics of fault weakening, and the scaling of slip rate, slip magnitude, and seismic hazard.