The Taigu fault zone is one of the major 12 active boundary faults of the Shanxi fault-depression system, located on the eastern boundary of the Jinzhong basin. As the latest investigation indicated, the fault zone ha...The Taigu fault zone is one of the major 12 active boundary faults of the Shanxi fault-depression system, located on the eastern boundary of the Jinzhong basin. As the latest investigation indicated, the fault zone had dislocated gully terrace of the first order, forming fault-scarp in front of the loess mesa. It has been discovered in many places in ground surface and trenches that Holocene deposits were dislocated. The latest activity was the 1303 Hongdong earthquake M=8, the fault appeared as right-lateral strike-slip with normal faulting. During that earthquake, the Taigu fault together with the Mianshan western-side fault on the Lingshi upheaval and the Huoshan pediment fault on the eastern boundary of the Linfen basin was being active, forming a surface rupture belt of 160 km in length. Moreover, the Taigu fault were active in the mid-stage of Holocene and near 7 700 aB.P. From these we learnt that, in Shanxi fault-depression system, the run-through activity of two boundary faults of depression-basins might generate great earthquake with M=8.展开更多
The Taigu fault zone is one of the major 12 active boundary faults of the Shanxi fault-depression system, locatedon the eastern boundary of the Jinzhong basin. As the latest investigation indicated, the fault zone had...The Taigu fault zone is one of the major 12 active boundary faults of the Shanxi fault-depression system, locatedon the eastern boundary of the Jinzhong basin. As the latest investigation indicated, the fault zone had dislocatedgully terrace of the f1rst order, forming fault-scarp in front of the loess mesa. It has been discovered in many placesin ground surface and trenches that Holocene deposits were dislocated. The latest activity was the 1303 Hongdongearthquake M=8, the fault appeared as right-lateral strike-slip with normal faulting. During that earthquake, theTaigu fault together with the Mianshan western-side fault on the Lingshi upheaval and the Huoshan pediment faulton the eastern boundary of the Linfen basin was being active, forming a surface rupture belt of 160 km in length.Moreover, the Taigu fault were active in the mid-stage of Holocene and near 7 700 aB.P. From these we learnt that,in Shanxi fault-depression system, the run-through activity of two boundary faults of depression-basins mightgenerate great earthquake with M=8.展开更多
A comprehensive study on regional stress field around the Taigu fault zone in Shanxi Province,China,was performed in this study.To get a better understanding of the present-day stress status in this area,31 focal mech...A comprehensive study on regional stress field around the Taigu fault zone in Shanxi Province,China,was performed in this study.To get a better understanding of the present-day stress status in this area,31 focal mechanisms of M_L≥3 earthquakes since 1965 were compiled,and the best stress tensor was then inverted based on the database.Additionally,magnetic fabrics along the Taigu fault zone were investigated to get an indication of the regional stress field in the past.Our results show that the present-day stress field around the Taigu fault zone is characterized by astable NW-SE extension with a strikeslip component,consistent with the geological surveys and recent GPS data.Results from magnetic fabrics indicate that the orientations of principal stress axes from magnetic fabrics of sedimentary rocks in Neogene coincide to the orientations of principal stress axes from focal mechanisms.The south segment of the Taigu fault displays more complicated magnetic fabrics and more activity of moderate earthquakes.It is connected with the Mianshan west fault and intersects with NW-SE striking Fenyang fault and the north fault of the Lingshi uplift at the south edge of Taiyuan basin.This may be the area needing more attention in terms of seismic risk along the Taigu fault.展开更多
基金Chinese Joint Seismological Science Foundation (201017).
文摘The Taigu fault zone is one of the major 12 active boundary faults of the Shanxi fault-depression system, located on the eastern boundary of the Jinzhong basin. As the latest investigation indicated, the fault zone had dislocated gully terrace of the first order, forming fault-scarp in front of the loess mesa. It has been discovered in many places in ground surface and trenches that Holocene deposits were dislocated. The latest activity was the 1303 Hongdong earthquake M=8, the fault appeared as right-lateral strike-slip with normal faulting. During that earthquake, the Taigu fault together with the Mianshan western-side fault on the Lingshi upheaval and the Huoshan pediment fault on the eastern boundary of the Linfen basin was being active, forming a surface rupture belt of 160 km in length. Moreover, the Taigu fault were active in the mid-stage of Holocene and near 7 700 aB.P. From these we learnt that, in Shanxi fault-depression system, the run-through activity of two boundary faults of depression-basins might generate great earthquake with M=8.
基金Chinese Joint Seismological Science Foundation (201017).
文摘The Taigu fault zone is one of the major 12 active boundary faults of the Shanxi fault-depression system, locatedon the eastern boundary of the Jinzhong basin. As the latest investigation indicated, the fault zone had dislocatedgully terrace of the f1rst order, forming fault-scarp in front of the loess mesa. It has been discovered in many placesin ground surface and trenches that Holocene deposits were dislocated. The latest activity was the 1303 Hongdongearthquake M=8, the fault appeared as right-lateral strike-slip with normal faulting. During that earthquake, theTaigu fault together with the Mianshan western-side fault on the Lingshi upheaval and the Huoshan pediment faulton the eastern boundary of the Linfen basin was being active, forming a surface rupture belt of 160 km in length.Moreover, the Taigu fault were active in the mid-stage of Holocene and near 7 700 aB.P. From these we learnt that,in Shanxi fault-depression system, the run-through activity of two boundary faults of depression-basins mightgenerate great earthquake with M=8.
基金partly funded by Open Fund of State Key Laboratory of Earthquake Dynamics,CEA(LED2011B05)the Foundation for the Returned Overseas of Shanxi Province(121)the National Science Fund of Shanxi Province(Youth,2010021005)
文摘A comprehensive study on regional stress field around the Taigu fault zone in Shanxi Province,China,was performed in this study.To get a better understanding of the present-day stress status in this area,31 focal mechanisms of M_L≥3 earthquakes since 1965 were compiled,and the best stress tensor was then inverted based on the database.Additionally,magnetic fabrics along the Taigu fault zone were investigated to get an indication of the regional stress field in the past.Our results show that the present-day stress field around the Taigu fault zone is characterized by astable NW-SE extension with a strikeslip component,consistent with the geological surveys and recent GPS data.Results from magnetic fabrics indicate that the orientations of principal stress axes from magnetic fabrics of sedimentary rocks in Neogene coincide to the orientations of principal stress axes from focal mechanisms.The south segment of the Taigu fault displays more complicated magnetic fabrics and more activity of moderate earthquakes.It is connected with the Mianshan west fault and intersects with NW-SE striking Fenyang fault and the north fault of the Lingshi uplift at the south edge of Taiyuan basin.This may be the area needing more attention in terms of seismic risk along the Taigu fault.
