Southern San Andreas Fault Seismicity is Consistent with the Gutenberg-Richter Magnitude-Frequency Distribution
Southern San Andreas Fault Seismicity is Consistent with the Gutenberg-Richter Magnitude-Frequency Distribution
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南圣安德烈亚斯断层地震活动与古腾堡-里克特震级频率分布一致
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
K. Felzer
中科院分区：
文献类型：
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作者：
M. Page;K. Felzer
通常观察到在某些主要断层上的地震（GR）分布的任何收集的地震量。这与其他观察结果一起导致了特征地质地震假说的公式，该假设认为，相对于大夸张速率，小对中的地震速率在大断层上永久较低（Wesnousky等，，Wesnousky等。 1983; Schwartz and Coppersmith，1984年）。
我们检查了南部圣安德烈亚斯断层（SSAF）的近期小型地震与古震态记录之间的差异，假设差异可以解释为时间的变化，而不是与GR统计数据通过合理的假设，将大小地震速率带入对准一致的速率变化与流行型余震序列建模的速率变化的大小变化的大小，在这种情况下，大地震的余震触发驱动地震速率的强烈波动，地震速率发生了强大的波动。在所有磁性中，所有必要的速率变化也与全球其他断层观察到的速率变化与SSAF上暂时的大地质量爆发的古呼吸观察一致。自1857年以来。
The magnitudes of any collection of earthquakes nucleating in a region are generally observed to follow the Gutenberg–Richter (GR) distribution. On some major faults, however, paleoseismic rates are higher than a GR extrapolation from the modern rate of small earthquakes would predict. This, along with other observations, led to the formulation of the characteristic earthquake hypothesis, which holds that the rate of small‐to‐moderate earthquakes is permanently low on large faults relative to the large‐earthquake rate (Wesnousky et al. , 1983; Schwartz and Coppersmith, 1984).
We examine the rate difference between recent small‐to‐moderate earthquakes on the southern San Andreas fault (SSAF) and the paleoseismic record, hypothesizing that the discrepancy can be explained as a rate change in time rather than a deviation from GR statistics. We find that with reasonable assumptions, the rate changes necessary to bring the small and large earthquake rates into alignment agree with the size of rate changes seen in epidemic‐type aftershock sequence modeling, where aftershock triggering of large earthquakes drives strong fluctuations in the seismicity rates for earthquakes of all magnitudes. The necessary rate changes are also comparable to rate changes observed for other faults worldwide. These results are consistent with paleoseismic observations of temporally clustered bursts of large earthquakes on the SSAF and the absence of M ≥7 earthquakes on the SSAF since 1857.