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给出了地震动预测方程(GMPE)估计地震与海啸预警系统震级的新应用。该技术结合了井下强震记录和地面记录,所用的数据均来自基岩强震观测台网(KiK-net)台站。我们分析了由日本地球科学与防灾研究所(NIED)提供的KiK-net台网1998~2010年期间记录的矩震级(M)5.0~8.1地震的强地震动数据。我们使用井下地震仪记录的地震动峰值加速度(PGA)大于10cm/s2的2 160个强震动加速度图和地面地震仪记录的地震动峰值加速度大于80cm/s2的890个波形,来推导日本的地震动峰值加速度和地震动峰值速度(PGV)的地震动预测方程。这些地震动预测方程是确定区域震级的基础。我们分别对井下记录和地面记录确定了由地震动峰值加速度值预测的震级(MPGA)和由地震动峰值速度值预测的震级(MPGV)。只要每个事件至少有20个可用记录,MPGA和MPGV就与事件的矩震级具有很强的相关性。结果显示由井下数据得到的MPGV在估计的震级中标准偏差最小,是对地震震级的精确早期评估。我们认为,加入强震发生后迅即得到的井下强地震动记录显著提高了地震震级估计的精度,改善了地震和海啸预警系统的性能。
The new application of GMPE in estimating earthquake and tsunami warning system magnitude is given. The technology combines well-bore downhole and ground-based recordings with data from the KiK-net bedrock station. We analyzed the strong ground motion data recorded by the KiK-net network provided by the Japan Institute of Earth Sciences and Disaster Prevention (NIED) during the period from 1998 to 2010, with moment magnitude (M) 5.0-8.1. We used 2 160 strong seismic acceleration maps with a PGA greater than 10 cm / s2 recorded by a downhole seismometer and 890 waveforms with a peak acceleration greater than 80 cm / s2 recorded by a surface seismometer to derive earthquakes in Japan Earthquake Prediction Equation of Dynamic Peak Acceleration and Ground Motion Peak Velocity (PGV). These ground motion prediction equations are the basis for determining regional magnitude. We determined MPGA predicted by the peak acceleration of ground motion and MPGV predicted by the peak ground velocity of ground motion, respectively, for downhole and ground records. As long as there are at least 20 available records for each event, MPGA and MPGV have a strong correlation with the incident moment magnitude. The results show that the MPGV derived from downhole data has the smallest standard deviation in the estimated magnitude and is an accurate early assessment of the magnitude of the earthquake. In our opinion, the strong ground motion records obtained immediately after the occurrence of strong earthquakes significantly improve the accuracy of earthquake magnitude estimates and improve the performance of earthquake and tsunami warning systems.