烈度仪用于地震预警的可靠性研究——以高雄M_S6.8地震为例

Reliability of seismic intensity instrument used in earthquake early warning:Taking the Gaoxiong M_S6.8 earthquake as an example

以2016年2月6日我国台湾高雄MS6.8地震中烈度仪观测网的实际记录为研究对象,通过对烈度仪台站的震相捡拾结果精度、峰值地震动衰减关系适用性、预警震级计算结果准确性等3方面的对比分析,研究了烈度仪用于地震预警时的优势和可靠性,并讨论了可能存在的问题和风险.研究结果表明:对于震中附近具有较高信噪比的烈度仪台站,采用现有震相捡拾方法即可获得较准确的震相到时信息;现有的地震动衰减关系并不完全适用于烈度仪台网,直接应用这些关系式时存在一定风险;基于密集布设的烈度仪观测台网,在较短时间即可获取大量信息,采用已有预警震级估算方法的计算结果有较高的准确性.

Based on the seismic intensity instrument（SSI）records of Gaoxiong MS6.8 earthquake in Taiwan,China which occurred on February 6,2016,we studied the advantage and reliability of SSI used in earthquake early warning（EEW）through the analysis on precision of phase pick,applicability of peak ground motion attenuation relationships and accuracy of earthquake magnitude estimation results.Meanwhile,we also discussed shortcuts and risks of using SSI during the EEW process.The results showed that for SSI stations with near-epicenter and high signal to noise ratio（SNR）,the existing phase pick methods are applicable to obtain accurate P phase arrival time.The existing peak ground motion attenuation laws may not fully apply to SSI stations,and a certain risk exists when apply them to SSI station directly.As a result of dense SSI stations layout,agreat quantity of useful information may be acquired in a short time,which is very favorable for earthquake magnitude estimation during the EEW process,and magnitude estimation results could have a good accuracy by using existing methods.