Pontificia Universidad Católica de Chile, Department of Structural and Geotechnical Engineering, Santiago, Chile.
Research Center for Integrated Disaster Risk Management (CIGIDEN), Santiago, Chile.
Sci Rep. 2020 May 21;10(1):8399. doi: 10.1038/s41598-020-65412-3.
Variability characterization of tsunami generation is quintessential for proper hazard estimation. For this purpose we isolate the variability which stems solely from earthquake spatial source complexity, by simulating tsunami inundation in the near-field with a simplified digital elevation model, using nonlinear shallow water equations. For earthquake rupture, we prescribe slip to have a log-normal probability distribution function and von Kármán correlation between each subfault pair, which we assume decreases with increasing euclidean distance between them. From the generated near-field inundation time-series, emanating from several thousand synthetic slip realizations across a magnitude 9 earthquake, we extract several tsunami intensity measures at the coast. Results show that all considered tsunami intensity measures and potential energy variability increase with increasing spatial slip correlations. Finally, we show that larger spatial slip correlations produce higher tsunami intensity measure exceedance probabilities within the near-field, which highlights the need to quantify the uncertainty of earthquake spatial slip correlation.
海啸生成的可变性特征对于正确的灾害评估至关重要。为此，我们通过使用非线性浅水方程，在简化的数字高程模型上模拟近场海啸淹没，从而隔离仅源于地震空间源复杂性的可变性。对于地震破裂，我们规定滑动具有对数正态概率分布函数和每个子断层对之间的 von Kármán 相关性，我们假设它们随它们之间的欧几里得距离的增加而减小。从在 9 级地震中跨越数千个合成滑动实现生成的近场淹没时间序列中，我们在沿海地区提取了几个海啸强度度量。结果表明，所有考虑的海啸强度度量和位能变异性都随着空间滑动相关性的增加而增加。最后，我们表明，较大的空间滑动相关性会在近场中产生更高的海啸强度度量超越概率，这突出了量化地震空间滑动相关性不确定性的必要性。
