【摘要】 利用四川和云南区域数字地震台网震相到时资料,并结合Hypo2000+Hypo DD对2008年8月30日攀枝花MS6.1地震序列进行了定位。定位结果表明,地震序列的震中在空间上呈近SN向展布,余震密集区长度约为30km,主震震源深度约为14km。序列深度的分布范围主要为0~4、5~20km,而4~5km范围显示为明显的少震层。沿序列长轴的深度剖面显示,余震区中段存在1个不规则的少震的"空区",为1955年634级地震的破裂区,该地震发生在空区的南端。分析认为,2008年8月30日攀枝花MS6.1地震是因汶川8.0级地震后的应力调整造成未破裂的小凹凸体发生破裂所致。余震密集分布区沿垂直于破裂长轴的两个剖面则显示了在其北端地震震源分布更深,且断层面向NW倾斜,与已知的红格断裂的倾向一致。更多还原

【Abstract】 The Panzhihua MS6. 1 earthquake sequence on August 30,2008,which was relocated by the Hypo2000 + Hypo DD method using the phase data from the Sichuan and Yunnan Regional Digital Seismic Network,showed that the epicenters distribute in NS,the length of the dense aftershocks’ region is about 30 km,and the main shock is about 14 km in depth. The sequence is separated in layers of 0 ~ 4km and 5 ~ 20 km in depth,then the 4 ~ 5km embodies an apparent earthquake absence layer. The cross-section along the fracture’s long axis shows there is a irregular seismic gap in the middle segment of the aftershock region,that is the crack region of the M63/4 earthquake in 1955,and this earthquake occurred in the south of the gap. We believed that the Panzhihua MS6. 1 earthquake sequence on August 30,2008 was a result from the residual asperity cracking forced by the stress adjustment of the Wenchuan MS8. 0 earthquake. The other two profiles perpendicular to the long axis show the north segment is more deeper and dips to NW,and this is correspondent to the known Hongge fault.更多还原