摘要
应用交切法对2003年4月17日德令哈地震序列的ML=6.7主震和截止至2003年10月25日的ML小于1.0级的余震,共117次地震事件进行了初始定位,并以双差地震定位法对这些地震重新进行精确定位。认为德令哈地震序列的主震震中位置为37.566°N,96.509°E,震源深度为13km,余震震源空间位置分布与哈佛大学震源机制解给出的走向为294°的节面一致。德令哈地震序列重新精确定位的结果清楚地表明了穿过震区的走向NWW—SEE、倾向NE的大柴旦—宗务隆山现代活动断裂带是这次德令哈地震序列的发震构造,同时表明该区域应力场水平最大主应力方向范围大致在N24°E—N34°E。
The authors made initial location of the main shock of ML = 6.7 and aftershocks of totally 117 events with magnitude ML 〉 1.0 for Delingha earthquake sequence till October 25, 2003, using the location intersection technique, and relocated 117 events using Double Difference Algorithm. It is known that the epicenter of the main shock was 37. 566°N and 96. 509°E, and the focal depth of the main shock was 13 km. The distribution of the aftershocks epicenters was consistent with the fault plane of 294° obtained from the focal mechanism of Harvard. The relocation results for the Delingha earthquake sequence clearly indicate that the seismogenic structure of the Delingha earthquake sequence is the NWW-SEE striking and NE-dipping Da Qaidam-Zongwulong Mountain modem active fault belt through the focal region. It is also indicatcd that the maximum horizontal main stress in this regional stress field is in the direction of about N24°E to N34°E.
出处
《物探与化探》
CAS
CSCD
2006年第1期79-82,共4页
Geophysical and Geochemical Exploration
基金
中国地质调查局项目(20010201)
关键词
德令哈地震序列
地震重新定位
发震构造
震源过程
Delingha earthquake sequence
earthquake relocation
seismogenic structure
earthquake source proces
