地震超剪切破裂研究现状

Review of the State-of-the-art Researches on Earthquake Super-shear Rupture

地震断层的破裂速度是地球物理学和地震学研究中重要的一个参数,以往的相关研究多是基于或者关注于断层破裂速度小于或接近于剪切波速时的情况,但是随着宽频带地震学的发展,在实际地震中已经观测到了一些超剪切波破裂速度的地震。为了解地震超剪切破裂相关研究的现状和发展趋势,基于大量相关研究文献,从地震超剪切破裂的概念、断层的极限破裂速度和超剪切破裂的初步原因出发,综述了地震超剪切破裂在地震观测数据、实验室实验、理论分析以及数值模拟等方面的研究现状,并提出了一些需要探讨和进一步研究的问题。

The rupture speed of the earthquake fault rupture is a key parameter in geophysics and seismology researches. It is also an important factor in the strong ground motion modeling for earthquake engineering. In the past few decades, many studies have been focusing on or based on condition that the fault rupture speed be smaller than the local shear wave speed of the earth＇s crust. While with the development of modern broadband seismology and laboratory technique, evidences of earthquake fault rupture speed great than the local shear wave speed have been detected both in the real earthquakes observation and in laboratory experiments. In order to have an over-all view on earthquake super-shear rupture related studies, this paper summarized abundant of classical and state-of- the-art researches. Based on the study results, this paper firstly introduced the concepts of super-shear rupture, the limitation speed of crack rupture and then discussed some reasons that may cause a super-shear rupture. And then, studies on super-shear rupture are summarized in three aspects, including the real earthquake recording data based studies, the laboratory experiments studies, and theory and numerical modeling studies. In the end the some conclusions and discussions are given, it is suggested that the study for modeling of strong ground motion and charac- terization of ground motion under super-shear rupture are very essential fields to be noticed in the future works.