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简述了苍山ＭＳ５．２地震的基本概况，分析了苍山５２级地震构造背景，据这次地震的余震空间分布、等震线长轴、震源机制解、地震活动条带和地质资料分析认为北西向的苍山新泰断裂和北东向的荣成临沂断裂可能是苍山５２级地震的地震断层。在１９８５年６月以前，鲁南地区的地震活动呈随机分布，１９８５年６月以后ＭＬ≥３．０地震主要集中在新泰苍山莒县之间的三角地带，来回迁移；１９７４年以后沿苍山尼山断裂的ＭＬ≥３．０地震都发生在５２级地震震中附近，说明在苍山尼山断裂与沂沭断裂带交汇区西侧较长时间的能量积蓄。苍山５２级地震前最后发生的两个ＭＬ≥２．０地震与苍山５２级地震震中形成沿地震断层的临震小震活动条带。
The basic situation of Cangshan MS5.2 earthquake is briefly described. The tectonic setting of Cangshan M5.2 earthquake is analyzed. According to the aftershock spatial distribution, the long axis of isoseismic line, focal mechanism solution, seismic activity band and geological data analysis It is considered that the Cangshan-Xintai fault in the northwest direction and the Rongcheng-Linyi fault in the northeast direction may be the seismic faults of the Cangshan M 2. 2 earthquake. Before June 1985, the seismic activity in the Lunan area was randomly distributed. After June 1985, ML≥3.0 earthquakes mainly concentrated in the delta between Xintai-Cangshan-Juxian County and migrated back and forth. After 1974 The ML≥3.0 earthquakes along the Cangshan-Nishan fault all occurred near the epicentral distance of the M 2 2 earthquake, indicating the energy accumulation for a long time on the west side of the intersection of Cangshan-Nishan fault and Yishu fault zone. Two ML ≥ 2.0 earthquakes that occurred before Cangshan 5 2 Earthquake and the epicenter of the M 2 2 Earthquake in Cangshan formed an active seismic activity zone along the seismic fault.