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本文从ＰＤＲ－２数字化近源（６２ｋｍ≤△≤４２ｋｍ）台网记录的丽江余震中初选了７４个地震，初定了震中位置，震中方位角。用相应的台网数据处理技术，研究了丽江地震序列的体波谱。对震级２５≤Ｍ≤５７、地震矩２１４０≤ｏｎｇＭＯ≤２３２８的地震，得出了丽江地区地震系列的震源参数；以及Ｐ波、Ｓ波的ｏｇＭＯ与Ｍｄ的关系式分别为：ｏｇＭＯｐ＝０６２Ｍｄ＋１９９３；ｏｇＭＯｓ＝０５９Ｍｄ＋１９６１。波谱拐角频率受地震辐射方向的调制，且与接受台站的场地响应有关。Ｐ波的拐角频率一般大于Ｓ波的拐角频率，平均拐角频率比为ｆＯ（ｐ）／ｆＯ（ｓ）＝１３。提出了归一化应力降的概念，给出了Ｗ（归一化应力降）随时间的分布。震源平均破袭尺度为４００多米。平均震源深度为９７ｋｍ。
In this paper, 74 earthquakes are initially selected from the aftershocks of Lijiang recorded from PDR-2 digitized near-site (62km≤Δ≤42km) network, and the epicenter and the azimuth of the epicenter are initially determined. With the corresponding network data processing technology, the body wave spectrum of Lijiang earthquake sequence is studied. For the earthquakes with magnitudes of 25≤M≤57 and seismic moments of 2140≤ongMO≤2328, the source parameters of the series of earthquakes in Lijiang area are obtained; and the ogMO and Md of P-wave and S-wave The relations are: ogMOp = 062Md + 1993; ogMOs = 059Md + 1961. The spectral corner frequency is modulated by the direction of the seismic radiation and is related to the site response of the receiving station. The corner frequency of P wave is generally larger than the corner frequency of S wave, and the average corner frequency ratio is fO (p) / fO (s) = 1.3. The concept of normalized stress drop is proposed and the distribution of W (normalized stress drop) over time is given. The source of the average attack size of more than 400 meters. The average focal depth is 97km.