江苏数字地震台网P波谱震级和地震辐射能的计算

Calculation of P-wave Spectrum Magnitude and Seismic Radiation Energy of Jiangsu Digital Seismic Network

基于江苏数字地震台网的宽频带记录,对38次M≥5.0地震的P波谱震级M_(P)进行测定,对地震的辐射能量进行了估算。结果表明:本文测定的M_(P)与中国地震台网中心(CENC)测定的MS、德国地学中心(GFZ)测定的MW具有很好的一致性,与该2种震级之间的平均偏差分别约为0.17和0.10级,基本小于世界主要地震机构之间对同一震级的测定误差(约0.2级);同时,基于M_(P)估算的地震辐射能与基于修正G-R关系由MS震级换算获得的结果十分接近,两者平均能量之比约为1.1,表明M_(P)与P波群(P+pP+sP)能量流是基本等效的。因此,基于宽频带数字记录测定中强地震的P波谱震级以及地震辐射能是可行的,且测定过程简便。

In this paper,based on the broadband records of Jiangsu Digital Seismic Network,we measured the P-wave spectrum magnitude(M_(P))of moderate and strong earthquakes,and estimated the seismic radiation energy.The results show that there is a good consistency between the M_(P) measured in this paper and the results of M_S measured by China Seismic Networks Center(CENC)and M_W measured by German Geoscience Center(GFZ).The average deviations between M_(P) and two magnitudes are only about 0.17 and 0.10,which are basically less than the measurement error(generally about 0.2)between the same magnitude of the world’s major earthquake agencies.At the same time,the seismic radiation energy estimated based on M_(P) is very close to that obtained from the conversion of M_S based on the modified G-R relationship,and the ratio of their average energy is about 1.1,which shows that the energy flow of M_(P) and the P-wave group(P+pP+sP)are basically equivalent.So,it is feasible to determine the P-wave spectrum magnitude and seismic radiation energy of moderate and strong earthquakes based on broadband digital records,and the measurement process is siM_(P)le and fast.