On 25 November 2016（14:24:30 UTC）, an Mw6.6 earthquake occurred in Aketao county of Xinjiang. We derived the coseismic deformation field of the earthquake from ESA’s Sentinel-1 B images and inverted the fault geome...On 25 November 2016（14:24:30 UTC）, an Mw6.6 earthquake occurred in Aketao county of Xinjiang. We derived the coseismic deformation field of the earthquake from ESA’s Sentinel-1 B images and inverted the fault geometry and slip distribution by using a homogenous half-space elastic model and the Steepest Decent Method（SDM） program. The slip model shows that the rupture plane is about 68 km in length and 40 km in width and has an average strike of 105.2°SE and an average dip of 76.0°S. The average amount of slip is-0.16 m and the maximum amount of slip is 0.59 m. The estimated seismic moment is 1.31 × 1019 N·m and the corresponding moment magnitude is Mw6.68. The dislocation is mainly distributed in the depth of 5-22 km, where the rupture center is located at 39.170 E, 74.38°N, and a depth of-8.8 km, so this earthquake is a shallow earthquake. In terms of the tectonic settings, the earthquake was triggered by the release of residual stresses on the seismogenic Muji fault. The ruptures were stimulated simultaneously by the main shock, which made the slip distribution pattern of a strike-slip fault with a double fracture. Due to the tectonic setting and the seismic gap between the ruptures, the Muji fault would have a risk of rupture to some extent and trigger an earthquake in future.展开更多
In this study,data from the Xinjiang regional network and IRIS shared global stations are used to relocate the Akto MS6. 7 earthquake sequence on November 25,2016 by using double difference location method. Three eart...In this study,data from the Xinjiang regional network and IRIS shared global stations are used to relocate the Akto MS6. 7 earthquake sequence on November 25,2016 by using double difference location method. Three earthquakes of MS4. 8,MS6. 7 and MS5. 0 are inverted by using the g CAP method,and the focal mechanism solutions are obtained.According to the results of relocating,the location of the main shock is 39. 22°N,73. 98°E,the distribution of the earthquake sequence is about 70 km in length,and the focal depth is mainly within the range of 5-20 km. The plane and depth profiles of the earthquake sequence show that aftershocks extended in SEE direction after the main shock and the dip angle of fault plane is steep. Focal mechanism results show that the three earthquakes are characterized by strike-slip movement. Based on the results of field geological investigation,it is inferred that the seismogenic fault of the Akto earthquake is Muji fault,which is located at the northernmost end of the Kongur extensional system.The possible cause of this earthquake is that the Indian Plate continues to push northward,and during this compression process,the Indian Plate is affected by the clockwise rotation of the Tarim basin,which causes the accumulation of right-lateral action of the Muji fault,resulting in this earthquake.展开更多
2016年11月25日在我国新疆克孜勒苏州阿克陶县发生M_S6.7地震(阿克陶M_S6.7地震).我们收集国内外地震资料,对主震及4级以上余震进行了重新定位和震源机制反演,对434次余震进行了双差定位,对主震震源过程进行了反演确定和复杂性分析,并...2016年11月25日在我国新疆克孜勒苏州阿克陶县发生M_S6.7地震(阿克陶M_S6.7地震).我们收集国内外地震资料,对主震及4级以上余震进行了重新定位和震源机制反演,对434次余震进行了双差定位,对主震震源过程进行了反演确定和复杂性分析,并基于反演确定的有限动态源模型估计了此次地震的烈度分布.结果表明:这次地震发生在当地一个近乎东西向展布的小型盆地内,很可能由一条新断层或隐伏断层的活动所致.发震断层近乎直立,近东西向展布,总体上表现为右旋走滑.破裂首先向西扩展,紧接着向东,随后向东西两个方向同时扩展,然后西侧破裂首先停止,东侧破裂继续,最后破裂在东侧停止,整个过程持续一20 s,释放地震矩1.08 X 10^(19)N·m,相当于M_w6.6.破裂过程最终形成两个位错高值区,分别位于初始破裂点的东西两侧,西侧高值区规模较小,东侧区规模较大.根据烈度估计,烈度椭圆长轴方向与主震破裂方向以及余震展布方向一致,最大烈度约为Ⅸ度,主要集中在震中以东很小的区域,Ⅷ度区呈纺锤形,分布于震中东西两侧,Ⅴ至Ⅶ度区呈椭圆形,总体上东侧烈度大于西侧.展开更多
基金supported by the National Science Foundation of China(No.41474097 and No.41731071)
文摘On 25 November 2016（14:24:30 UTC）, an Mw6.6 earthquake occurred in Aketao county of Xinjiang. We derived the coseismic deformation field of the earthquake from ESA’s Sentinel-1 B images and inverted the fault geometry and slip distribution by using a homogenous half-space elastic model and the Steepest Decent Method（SDM） program. The slip model shows that the rupture plane is about 68 km in length and 40 km in width and has an average strike of 105.2°SE and an average dip of 76.0°S. The average amount of slip is-0.16 m and the maximum amount of slip is 0.59 m. The estimated seismic moment is 1.31 × 1019 N·m and the corresponding moment magnitude is Mw6.68. The dislocation is mainly distributed in the depth of 5-22 km, where the rupture center is located at 39.170 E, 74.38°N, and a depth of-8.8 km, so this earthquake is a shallow earthquake. In terms of the tectonic settings, the earthquake was triggered by the release of residual stresses on the seismogenic Muji fault. The ruptures were stimulated simultaneously by the main shock, which made the slip distribution pattern of a strike-slip fault with a double fracture. Due to the tectonic setting and the seismic gap between the ruptures, the Muji fault would have a risk of rupture to some extent and trigger an earthquake in future.
基金Co-sponsored by the Seismological Science and Technology Spark Program(XH19053)the Regular Project “Operation and Maintenance of the National Automatic Reporting Center(CSN/GSN)and System Optimization”
文摘In this study,data from the Xinjiang regional network and IRIS shared global stations are used to relocate the Akto MS6. 7 earthquake sequence on November 25,2016 by using double difference location method. Three earthquakes of MS4. 8,MS6. 7 and MS5. 0 are inverted by using the g CAP method,and the focal mechanism solutions are obtained.According to the results of relocating,the location of the main shock is 39. 22°N,73. 98°E,the distribution of the earthquake sequence is about 70 km in length,and the focal depth is mainly within the range of 5-20 km. The plane and depth profiles of the earthquake sequence show that aftershocks extended in SEE direction after the main shock and the dip angle of fault plane is steep. Focal mechanism results show that the three earthquakes are characterized by strike-slip movement. Based on the results of field geological investigation,it is inferred that the seismogenic fault of the Akto earthquake is Muji fault,which is located at the northernmost end of the Kongur extensional system.The possible cause of this earthquake is that the Indian Plate continues to push northward,and during this compression process,the Indian Plate is affected by the clockwise rotation of the Tarim basin,which causes the accumulation of right-lateral action of the Muji fault,resulting in this earthquake.
文摘2016年11月25日在我国新疆克孜勒苏州阿克陶县发生M_S6.7地震(阿克陶M_S6.7地震).我们收集国内外地震资料,对主震及4级以上余震进行了重新定位和震源机制反演,对434次余震进行了双差定位,对主震震源过程进行了反演确定和复杂性分析,并基于反演确定的有限动态源模型估计了此次地震的烈度分布.结果表明:这次地震发生在当地一个近乎东西向展布的小型盆地内,很可能由一条新断层或隐伏断层的活动所致.发震断层近乎直立,近东西向展布,总体上表现为右旋走滑.破裂首先向西扩展,紧接着向东,随后向东西两个方向同时扩展,然后西侧破裂首先停止,东侧破裂继续,最后破裂在东侧停止,整个过程持续一20 s,释放地震矩1.08 X 10^(19)N·m,相当于M_w6.6.破裂过程最终形成两个位错高值区,分别位于初始破裂点的东西两侧,西侧高值区规模较小,东侧区规模较大.根据烈度估计,烈度椭圆长轴方向与主震破裂方向以及余震展布方向一致,最大烈度约为Ⅸ度,主要集中在震中以东很小的区域,Ⅷ度区呈纺锤形,分布于震中东西两侧,Ⅴ至Ⅶ度区呈椭圆形,总体上东侧烈度大于西侧.
