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以波辐射发出的能量是了解地震破裂物理学所必需的一个参数,然而计算这种能量是困难的、不确定的。我们发展了一种新的计算辐射波能量和其他重要地震参数的混合方法。该方法以一种内部一致且客观的方式计算这些参数,可对参数和相关地震之间进行严格对比。此外,该方法不需要对数据作反褶积和滤波,所以,结果保留了记录的全部高频(成份)。我们用这种方法计算了19个近年来规模在M_u6.5～8.2之间的深源(深度>292km)地震的震源时间函数、地震矩、持续时间和辐射波能量。我们计算了3次最大地震的有效地震效率,基本结果为有效地震效率小于0.3。若地震破裂遵守Orowan模型,则破裂时平均摩擦应力和断层面上的最终剪应力相等,从而地震效率为1。但因测量到的地震效率小于1,在这些大的深震的破裂过程中,更多的能量是分布在摩擦中,且破裂时的平均摩擦应力比最终断层面应力要高。
The energy emitted by wave radiation is a parameter necessary to understand the physics of earthquake rupture, however, it is difficult and uncertain to calculate this energy. We have developed a new hybrid method of calculating radiant energy and other important seismic parameters. The method computes these parameters in an internally consistent and objective way, allowing for a rigorous comparison between parameters and related earthquakes. In addition, the method does not require deconvolution and filtering of the data, so the result retains all of the recorded high frequencies (components). Using this method, we calculated focal time functions, seismic moment, duration and radiant energy of 19 deep-source (depth> 292km) earthquakes with M_u 6.5 to 8.2 in recent years. We calculate the effective seismic efficiency of the three largest earthquakes, and the basic result is that the effective seismic efficiency is less than 0.3. If the earthquake ruptures follow the Orowan model, the average frictional stress at rupture is equal to the ultimate shear stress on the fault plane, so that the seismic efficiency is 1. However, because the measured seismic efficiency is less than 1, more energy is distributed in the friction during the deep deep earthquake rupture and the average frictional stress at rupture is higher than the final fault plane stress.