基于高频GPS峰值地动位移的震级标度探讨

Detection of Magnitude Scale Low Based on Peak Ground Displacement Obtained by the High-rate GPS Data

综合地震学地震震级公式和目前连续GPS研究震级标度的成果,使用国内外M_W5.9～9.1的17个地震事件的高频GPS测站的峰值地动位移数据,构建了新的基于GPS峰值地动位移(PGD)的震级标度关系。依据新建立的关系和实际数据分析认为,GPS峰值地动位移的震级标度关系适用于M_W5.6以上大地震的震级计算,并得到不同震级的地震使用该标度关系的震源距适用范围,提出使用场地校正项和震源辐射与传播路径校正项修正基于GPS峰值地动位移的震级标度关系。

A new magnitude scale relationship based on GPS peak geodynamic displacement(PGD) is constructed by synthesizing the magnitude formula of seismology and the results of current continuous GPS research on magnitude scale, using the peak geodynamic displacement data of 17 high-rate GPS stations with seismic events between MW5.9 and 9.1 at home and abroad. According to the newly established relationship and the actual data analysis, it is considered that the magnitude scaling relation of GPS peak geodynamic displacement is suitable for magnitude calculation of larger earthquakes with MW ≥ 5.6, and the applicable range of focal distance for earthquakes with different magnitudes can be derived. This paper also presents that a wider range of the scaling relationship for estimating earthquake magnitude based on high-rate GPS' PGD can be obtained by using site correction, source radiation and propagation path correction.