Earthquake Magnitude Scaling Using Peak Ground Velocity Derived from High-Rate GNSS Observations
Earthquake Magnitude Scaling Using Peak Ground Velocity Derived from High-Rate GNSS Observations
复制标题
使用源自高速 GNSS 观测的峰值地速来缩放地震震级
DOI：
10.1785/0220190347
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发表时间：
2020-10
影响因子：
3.3
通讯作者：
Liu Jingnan
中科院分区：
文献类型：
--
作者：
Fang Rongxin;Zheng Jiawei;Geng Jianghui;Shu Yuanming;Shi Chuang;Liu Jingnan
对破坏性海啸和地震事件的快速反应需要快速确定地震震级。我们提出了一种新的方法，采用峰值地面速度（PGVs）来自全球导航卫星系统（GNSS）的数据来估计地震震级。以22个地震的1434条记录为约束条件，进行了回归分析，得到了一个PGV标度律。新方法的优点是PGV是从GNSS速度波形中提取的，可以很容易地使用广播GNSS星历计算。相比之下，峰值地面位移（PGD）取决于一个复杂的高精度GNSS处理的外部校正数据，其实现不能保持鲁棒不断，特别是在真实的时间。结果表明，PGV震级与矩震级的平均绝对偏差为0.26个震级单位，与PGD震级也有较好的一致性。我们进一步证明，GNSS衍生的PGV和修改后的Mercalli强度值可以与美国地质调查局ShakeMap产品的对应值一致，因此GNSS衍生的PGV有可能作为补充约束被包含在ShakeMap中，特别是在大地震的地震台站覆盖稀疏的地区。
Rapid response to destructive tsunami and seismic events requires rapid determination of the earthquake magnitude. We propose a new method that employs peak ground velocities (PGVs) derived from Global Navigation Satellite System (GNSS) data to estimate earthquake magnitudes. With a total of 1434 records from 22 events as the constraints, we perform the regression and obtain a PGV scaling law for magnitude determination. The advantage of the new method is that the PGVs are extracted from the GNSS velocity waveforms, which can be easily computed using broadcast GNSS ephemeris. In contrast, the peak ground displacement (PGD) depends on a sophisticated high-precision GNSS-processing subject to external correction data, realization of which cannot be kept robust constantly, especially in real time. The results show that the PGV magnitudes agree with reported moment magnitudes with mean absolute deviation of 0.26 magnitude units for the 22 events and also agree well with the PGD magnitude. We further demonstrate that GNSS-derived PGV and the modified Mercalli intensity values can be consistent with their counterparts from the U.S. Geological Survey ShakeMap products and therefore the GNSS-derived PGVs have the potential to be included in the ShakeMap as a complementary constraint, especially in areas with sparse seismic station coverage for large earthquake.