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为了更好地理解世界范围内检测到的慢滑动事件(SSE)的物理机制,探索了各种震源参数间的标度关系,并与地震的类似标度律进行了比较。这些标度关系突出慢滑动事件与地震之间的差异和相似性,并对复杂性程度和断层愈合表征有意义。对于观测的不同震级的地震,其静态应力降基本为常数。而慢滑动事件的静态应力降范围为0.01~1.0MPa,比地震低1~2个数量级,这可能与断层上的低应力状态有关。慢滑动的平均破裂速度范围从每秒几千米到每天几千米,在双对数空间中表现为随地震矩的增大而线性地减少,而地震事件的破裂速度几乎是常数。这种破裂速度与地震矩的反比关系可能与断层性质的多相性相关。慢滑动事件的持续时间与位错上升时间之比通常小于3,而地震通常大于3。这显示慢滑动事件的传播方式的脉冲状特性要比地震少,并说明破裂前沿后的愈合有延迟。通过对卡斯凯迪亚北部俯冲带慢滑动事件的复发时间统计表明,慢滑动事件具有弱时间可预测性和中等程度的反滑动可预测性(即事件的大小与前次事件的复发间隔为反相关),这或许表明事件间的愈合会随时间增加断层的强度。
In order to better understand the physical mechanism of slow-slip events (SSEs) detected worldwide, the scaling relationships between various source parameters were explored and compared with the analogous scale laws for earthquakes. These scaling relationships highlight the differences and similarities between slow-slip events and earthquakes and make sense for the degree of complexity and for the characterization of the healing of faults. For observed earthquakes of different magnitudes, the static stress drop is basically constant. However, the static stress drop of the slow slip event ranges from 0.01 to 1.0 MPa, which is 1-2 orders of magnitude lower than that of the earthquake, which may be related to the low stress state on the fault. The average rate of slow slip slows from several kilometers per second to several kilometers a day, decreases linearly with the increase of seismic moment in double logarithmic space, and the breaking rate of seismic events is almost constant. The inverse relationship between this rate of rupture and seismic moment may be related to the heterogeneity of fault properties. The ratio of the duration of a slow slip event to the time of dislocation rise is usually less than 3, whereas the earthquake is usually greater than 3. This shows that the slow-slip events propagate less pulsatile than the earthquakes and indicate a delay in healing after the rupture front. Based on the recurrent time statistics of the slow-slip event in the subduction zone in northern Cascais, it is shown that the slow-slip event has a weak time predictability and a moderate degree of anti-slip predictability (ie, the size of the event is opposite to that of the previous event Related), which may indicate that the healing between events will increase the intensity of the fault over time.