The Bohai Sea basin is located in the east to the Cenozoic rift basin of North China. It is a inner-land sea basin formed during Late Quaternary time. In this basin there are numerous active faults and many major eart...The Bohai Sea basin is located in the east to the Cenozoic rift basin of North China. It is a inner-land sea basin formed during Late Quaternary time. In this basin there are numerous active faults and many major earthquakes have occurred. Its major active tectonic zones are the northern section of the NE trending Yingkou-Weifang fault zone, Miaoxibei-Huanghekou-Linyi fault zone, and NW striking Beijing-Penglai fault zone, which intersect at the center of the Bohai Sea basin. These tectonic zones subdivide the sea area into four secondary neotectonic areas, which are subject to the recent tectonic stress field. Using the data of 38 focal plane solutions and 75 drill stress measurements, and the result of numerical modeling, we analyze the recent tectonic stress field of this region. Our result shows that this stress field is characterized by dominant horizontal or nearly horizontal stress. Its compres-sive stress is in the direction NE60~90, and the tensional stress is in NS-NW30. There are some differences of principal stress between secondary tectonic areas. A remarkable feature of the Bohai Sea basin is a conjugate shear rupture zone, which develops in the crust and is the major seismogenic structure.展开更多
By comprehension of earthquake focal mechanism solutions and the data of in-situ stress measurements, the tectonic stress field in Shanxi region has been summarized, which indicate that the stress state in this region...By comprehension of earthquake focal mechanism solutions and the data of in-situ stress measurements, the tectonic stress field in Shanxi region has been summarized, which indicate that the stress state in this region is different from that of its eastern surrounding regions. The next, by fitting the measured data, the boundary forces that influenced the distribution of the stress field in this region has been studied using inversion method. The inversion results showed the following messages: the effect of the boundary force between the blocks is the main determinative factor for the recent tectonic stress field in Shanxi and the regional material and its property is a secondary factor; the horizontal main stress of tectonic stress field in Shanxi region is consistent with the stretch of fault basins.展开更多
The recent stress field of China has been reconstructed in recent years by many researchers, who generally suggest that it must be related to the effect of adjoining plates. Based on the analysis on the forces and the...The recent stress field of China has been reconstructed in recent years by many researchers, who generally suggest that it must be related to the effect of adjoining plates. Based on the analysis on the forces and their directions along the respective sections of the plate boundaries of the east margin in China, the relation between the recent stress field of China and effect of adjoining plates are discussed by means of numerical simulation, and new arguments are offered.展开更多
基金National Natural Science Foundation of China (40238059, 40172101).
文摘The Bohai Sea basin is located in the east to the Cenozoic rift basin of North China. It is a inner-land sea basin formed during Late Quaternary time. In this basin there are numerous active faults and many major earthquakes have occurred. Its major active tectonic zones are the northern section of the NE trending Yingkou-Weifang fault zone, Miaoxibei-Huanghekou-Linyi fault zone, and NW striking Beijing-Penglai fault zone, which intersect at the center of the Bohai Sea basin. These tectonic zones subdivide the sea area into four secondary neotectonic areas, which are subject to the recent tectonic stress field. Using the data of 38 focal plane solutions and 75 drill stress measurements, and the result of numerical modeling, we analyze the recent tectonic stress field of this region. Our result shows that this stress field is characterized by dominant horizontal or nearly horizontal stress. Its compres-sive stress is in the direction NE60~90, and the tensional stress is in NS-NW30. There are some differences of principal stress between secondary tectonic areas. A remarkable feature of the Bohai Sea basin is a conjugate shear rupture zone, which develops in the crust and is the major seismogenic structure.
文摘By comprehension of earthquake focal mechanism solutions and the data of in-situ stress measurements, the tectonic stress field in Shanxi region has been summarized, which indicate that the stress state in this region is different from that of its eastern surrounding regions. The next, by fitting the measured data, the boundary forces that influenced the distribution of the stress field in this region has been studied using inversion method. The inversion results showed the following messages: the effect of the boundary force between the blocks is the main determinative factor for the recent tectonic stress field in Shanxi and the regional material and its property is a secondary factor; the horizontal main stress of tectonic stress field in Shanxi region is consistent with the stretch of fault basins.
文摘The recent stress field of China has been reconstructed in recent years by many researchers, who generally suggest that it must be related to the effect of adjoining plates. Based on the analysis on the forces and their directions along the respective sections of the plate boundaries of the east margin in China, the relation between the recent stress field of China and effect of adjoining plates are discussed by means of numerical simulation, and new arguments are offered.
