论文部分内容阅读
本文在波谱分析的基础上,对华北北部地区地震的波谱和震源参数进行了研究和探讨。初步结果表明:(1)地震波谱的高频衰减率与震级无关;P 波和 S 波拐角频率和拐角频率之比在1.7≤M_L≤4.0范围内与震级无明显关系;在 M_L>4.0时,随震级的增大而减小;地震波谱图形在1.7≤M_L≤4.0范围内基本没有明显变化,在 M_L>4.0时,波谱低于拐角频率的频段向低频缩小,而高于拐角频率的频段向低频扩展。(2)破裂速度和破裂尺度在1.7≤M_L≤4.0范围内与震级无明显关系。在 M_L>4.0时,随震级的增大而增大。(3)应力降和平均位错在1.7≤M_L≤4.0范围内随震级增大而增大,应力降与平均位错成线性关系,在M_L>4.0时,两者成非线性关系。(4)北京台网测定的震级 M_L 比美国加州测定的 M_L 约小0.2级左右。(5)实测地震波能量与震级 M_L 的关系同古登堡——李希特的震级——能量关系完全一致。
Based on the spectral analysis, this paper studies and discusses the spectrum and source parameters of the earthquake in the northern part of North China. The preliminary results show that: (1) the high frequency attenuation rate of the seismic wave spectrum has nothing to do with the magnitude; the ratio of the P-wave and S-wave corner frequencies to the corner frequencies has no obvious relationship with the magnitude in the range of 1.7≤M_L≤4.0; when M_L> 4.0, With the increase of magnitude, it decreases. The seismic spectrum does not change obviously in the range of 1.7≤M_L≤4.0. When M_L> 4.0, the band below the corner frequency of the spectrum shrinks to the low frequency, while the frequency band above the corner frequency Low-frequency expansion. (2) The rupture rate and rupture scale have no obvious relationship with magnitude in the range of 1.7≤M_L≤4.0. When M_L> 4.0, the magnitude increases. (3) The stress drop and the average dislocation increase with the increase of magnitude in the range of 1.7≤M_L≤4.0. The stress drop has a linear relationship with the average dislocation. When M_L> 4.0, the two are nonlinear. (4) The magnitude M_L measured by Beijing Network is about 0.2 or so smaller than the M_L measured by California. (5) The relationship between the measured seismic energy and magnitude M_L is completely consistent with the magnitude-energy relation of Gutenberg-Richter.