Journey to the centre of the earthquake; what affects earthquake source properties and radiated wavefields?

地震有可能造成巨大的人员、结构和经济破坏。产生的地震波的频率和震级是震源（滑动的断层带）和地震波传播沿着路径的产物。关于震源，特别是断层带的特征如何影响地震的滑动运动学，我们知之甚少。原则上，断层的摩擦特性加上围岩的弹性特性（它们将被断裂损伤所改变）都将对断裂特性的性质作出贡献。这些属性，如应力降和破裂速度，将决定地震的震源特征（例如，破裂的能量如何）和所产生的辐射波场。该项目将使用实验室实验和数值模拟相结合的方法来了解震源的性质如何受到断层周围围岩的影响。模拟的自发地震将在实验室中产生，在那里系统的关键特性可以被仔细控制和测量。将改变滑动断层周围块体的弹性性质，以观察破裂的合成性质（速度和振幅）。将建立破裂的数字模型，以便扩大结果的规模，预测地震破裂的大规模行为。

Earthquakes have the potential to cause enormous human, structural and economic devastation. The frequency and magnitude of the seismic waves produced are a product of the earthquake source - the fault zone that is slipping - and the path along which the seismic waves travel. Little is known about the seismic source, in particular how the characteristics of a fault zone affect the slip kinematics of an earthquake. In principal both the frictional properties of the fault plus the elastic properties of surrounding rock, which will have been modified by fracture damage, will contribute to the nature of the rupture properties. These properties, such as stress drop and rupture velocity, will dictate the source character of the earthquake (e.g., how energetic the rupture is) and the resultant radiated wavefield. This project will use a combination of laboratory experiments and numerical modelling to understand how the properties of the earthquake source are affected by the country rock surrounding a fault. Simulated spontaneous earthquakes will be produced in the laboratory where key properties of the system can be carefully controlled and measured. The elastic properties of the blocks surrounding the slipping fault will be varied to observe the resultant properties of the rupture (velocity and amplitude). Numerical modelling of the ruptures will be developed so that upscaling of the results can be made to predict the larger-scale behaviour of earthquake ruptures.