论文标题
地震性在关键时刻运行吗？
Is seismicity operating at a critical point?
论文作者
论文摘要
地壳内的地震性和断层的特征是许多缩放定律通常被解释为在相变的意义上存在与某种批判性相关的基本物理机制的存在。使用增强的流行型余震序列（ETA）模型，该模型解释了后台速率$μ（x，y）$的空间变异性，我们提出了对关键性的直接定量测试。我们使用扩展的期望最大化（EM）算法（包括$μ（x，y）$）校准了整个世界的ANSS目录，加利福尼亚州附近的地区和新西兰地区的Geonet目录。我们证明，先前研究中报道的临界性是虚假的，可以归因于ETAS模型分支比的校准中系统的向上偏置，而对于空间变异性则未正确考虑。我们通过执行伪前瞻性预测测试来验证具有空间变化的背景速率$μ（x，y）$的版本。地震性的非临界性对大事件的预测具有重大影响。
Seismicity and faulting within the Earth crust are characterized by many scaling laws that are usually interpreted as qualifying the existence of underlying physical mechanisms associated with some kind of criticality in the sense of phase transitions. Using an augmented Epidemic-Type Aftershock Sequence (ETAS) model that accounts for the spatial variability of the background rates $μ(x,y)$, we present a direct quantitative test of criticality. We calibrate the model to the ANSS catalog of the entire globe, the region around California, and the Geonet catalog for the region around New Zealand using an extended Expectation-Maximization (EM) algorithm including the determination of $μ(x,y)$. We demonstrate that the criticality reported in previous studies is spurious and can be attributed to a systematic upward bias in the calibration of the branching ratio of the ETAS model, when not accounting correctly for spatial variability. We validate the version of the ETAS model which possesses a space varying background rate $μ(x,y)$ by performing pseudo prospective forecasting tests. The non-criticality of seismicity has major implications for the prediction of large events.
