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了解地震破裂过程对于了解断层系统和地震危险是很重要的。关于断层破裂性质的若干假定已经提出,但还没有形成统一的理论(Brune,1979;Fukao and Furu-moto,1985;Ellsworth and Beroza,1995;Beroza and Ellsworth,1996;Dodgeet al,1996;Mori,1996;Mori and Kanamori,1996;Singhet al,1998;Steacy and McClos-key,1998;Kilb and Gomberg,1999;Sato and Kanamori,1999;Ohnaka,2000)。大多数被引用的概念上的假设是断层破裂的级联模型(Burne,1979;Ellsworth and Beroza,1995,1998;Kilb and Gomberg,1999)。在级联模型中,滑动在断层的一小段上开始,只要条件有利,并持续破裂,直至延伸到断层面。这个如同多米诺骨牌的理论有2个基本含义:小地震以大地震相同的方式开始,破裂过程是不确定性的;换句话说,直到破裂停止之前,地震大小是不能确定的。在本文中我们说明,事件最终大小与破裂最初几秒的地震能量辐射频谱成正比。我们推断,地震震级能在破裂完成之前被估算出来。这一发现意味着破裂过程在某种程度上是确定性的,并且具有破裂过程物理学的含义。
Understanding the earthquake rupture process is important to understand the fault system and seismic hazard. Several assumptions about the nature of fault rupture have been proposed but no unified theory has been developed (Brune, 1979; Fukao and Furu-moto, 1985; Ellsworth and Beroza, 1995; Beroza and Ellsworth, 1996; Dodge et al, 1996; Mori, 1996 ; Mori and Kanamori, 1996; Singhet al, 1998; Steacy and McClos-key, 1998; Kilb and Gomberg, 1999; Sato and Kanamori, 1999; Ohnaka, 2000). The most hypothetical hypotheses cited are fault-fracture cascades (Burne, 1979; Ellsworth and Beroza, 1995, 1998; Kilb and Gomberg, 1999). In the cascade model, the slip begins on a short segment of the fault, as long as the conditions are favorable, and continues to rupture until it extends to the fault plane. This domino-like theory has two basic meanings: a small earthquake starts in the same way as a large earthquake, and the rupture process is indeterminate; in other words, the magnitude of the earthquake can not be determined until the rupture ceases. In this paper, we show that the final event size is proportional to the energy spectrum of seismic energy in the first few seconds of rupture. We conclude that the magnitude of the earthquake can be estimated before the rupture is completed. This finding means that the rupture process is somewhat deterministic and has the meaning of rupture process physics.