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Viscoelastic stress change from the 1931 M_(w)7.8 Fuyun earthquake and its impacts on seismic activity around the Altai mountains
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作者 Yali Shao jiankun He +1 位作者 Xinguo Wang Youjia Zhao 《Geodesy and Geodynamics》 EI CSCD 2024年第4期326-337,共12页
The 1931 M_(w)7.8 Fuyun earthquake occurred around the Altai mountains, an intracontinental deformation belt with limited active strain-rate accumulation. To explore whether seismic activity in this deformation belt w... The 1931 M_(w)7.8 Fuyun earthquake occurred around the Altai mountains, an intracontinental deformation belt with limited active strain-rate accumulation. To explore whether seismic activity in this deformation belt was affected by stress interaction among different active faults, we calculate the Coulomb failure stress change(ΔCFS) induced by the Fuyun earthquake due to coseismic deformation of the elastic crust and postseismic viscoelastic relaxation of the lower crust and upper mantle. Numerical results show that the total ΔCFS at a 10-km depth produced by the Fuyun earthquake attains approximately 0.015-0.134 bar near the epicenter, and just before the occurrence of the 2003 M_(w)7.2 Chuya earthquake, which distances about 400 km away from the Fuyun earthquake. Among the increased ΔCFS,viscoelastic relaxation from 1931 to 2003 contributes to approximately 0.014-0.131 bar, accounting for>90% of the total ΔCFS. More importantly, we find that for the recorded seismicity in the region with a radius of about 270 km to the Fuyun earthquake from 1970 to 2018, the percentage of earthquakes that fall in positive lobes of ΔCFS resolved on the NNW-SSE Fuyun strike-slip fault, on the NWW-SEE Irtysh strike-slip fault, and on the NW-SE Kurti reverse fault is up to 67.22%-91.36%. Therefore, the predictedΔCFS suggests that the impact of the 1931 M_(w)7.8 Fuyun earthquake on seismic activity around the Altai mountains is still significant as to hasten occurrence of the 2003 M_(w)7.2 Chuya earthquake at a relatively far distance and to trigger its aftershocks in the near-field even after several decades of the mainshock. 展开更多
关键词 Altai mountains Fuyunearthquake Coulomb failure stress change Viscoelasticrelaxation seismic activity
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Late-Quaternary Slip Rate and Seismic Activity of the Xianshuihe Fault Zone in Southwest China 被引量:14
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作者 ZHANG Yongshuang YAO Xin +2 位作者 YU Kai DU Guoliang GUO Changbao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第2期525-536,共12页
The Xianshuihe fault zone is a seismo-genetic fault zone of left-lateral slip in Southwest China. Since 1725, a total of 59 Ms ≥ 5.0 earthquakes have occurred along this fault zone, including 18 Ms 6.0–6.9 and eight... The Xianshuihe fault zone is a seismo-genetic fault zone of left-lateral slip in Southwest China. Since 1725, a total of 59 Ms ≥ 5.0 earthquakes have occurred along this fault zone, including 18 Ms 6.0–6.9 and eight Ms ≥ 7.0 earthquakes. The seismic risk of the Xianshuihe fault zone is a large and realistic threat to the western Sichuan economic corridor. Based on previous studies, we carried out field geological survey and remote sensing interpretation in the fault zone. In addition, geophysical surveys, trenching and age-dating were conducted in the key parts to better understand the geometry, spatial distribution and activity of the fault zone. We infer to divide the fault zone into two parts: the northwest part and the southeast part, with total eight segments. Their Late Quaternary slip rates vary in a range of 11.5 mm/a –(3±1) mm/a. The seismic activities of the Xianshuihe fault zone are frequent and strong, periodical, and reoccurred. Combining the spatial and temporal distribution of the historical earthquakes, the seismic hazard of the Xianshuihe fault zone has been predicted by using the relationship between magnitude and frequency of earthquakes caused by different fault segments. The prediction results show that the segment between Daofu and Qianning has a possibility of Ms ≥ 7.0 earthquakes, while the segment between Shimian and Luding is likely to have earthquakes of about Ms 7.0. It is suggested to establish a GPS or In SAR-based real-time monitoring network of surface displacement to cover the Xianshuihe fault zone, and an early warning system of earthquakes and post seismic geohazards to cover the major residential areas. 展开更多
关键词 Xianshuihe fault zone earthquake left-lateral strike-slip fault slip rate seismic activity prediction
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The Crustal Structure and Seismic Activity in North China 被引量:4
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作者 Feng Rui Institute of Geophysics, State Seismological Bureau, Beijing Huang Guifang, Zheng Shuzhen, Wang Jun, Yan Huifen Geophysical Prospecting Party, State Seismological Bureau, Zhengzhou, Henan and Zhang Ruoshui Seismological Technique College, State Seismological Bureau, Yanjiao,Hebei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1989年第4期343-359,448-449,共19页
A layered crustal block model of North China has been constructed based on large amount of data from seismic sounding carried out in recent two decades. Some deep fault zones, such as the Zhangjiakou.Penglai and Tanch... A layered crustal block model of North China has been constructed based on large amount of data from seismic sounding carried out in recent two decades. Some deep fault zones, such as the Zhangjiakou.Penglai and Tancheng-Lujiang fault zones, divide the upper crust of North China into three upper crustal terranes and nine bolcks. There are distinct differences in velocity and depth distributions, which reflects Cenozoic block faulting in North China in the process of formation of the deep structure. The upper crust shows the features of transition in isostatic adjustment. The existence of a low-velocity layer in the middle crust is characteristic of the crustal structure in North China. There seems to be an increase of rheology of the rocks in the lower crust and a persistence of stable regional stress field. The patterns of the Moho on two sides of the Yanshan-Taihang Mountains are different. The relief of the Moho around Beijing, Shijiazhuang and Guangrao where the deep faults join together shows a quadrantal distribution in some degree. The dynamic sources for seismic activity are the NE-SW horizontal compression and the diapirism of the upper mantle. The middle and upper crust, especially the layered block structure has the most significant effects on seismicity, and the occurrence of earthquakes is more closely related to them than to the Moho. 展开更多
关键词 The Crustal Structure and seismic activity in North China activity
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Numerical calculations of tectonic stress field of Chinese mainland and its neighboring regions and their applications to explanation of seismic activity 被引量:2
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作者 焦明若 张国民 +1 位作者 车时 刘杰 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第2期137-147,共11页
This paper made a numerical simulation to the basic tectonic stress field of Chinese mainland and its neighboringregion using the visco-elasticity finite element model and the new published displacement rate result. M... This paper made a numerical simulation to the basic tectonic stress field of Chinese mainland and its neighboringregion using the visco-elasticity finite element model and the new published displacement rate result. Main contents include the simulation of maximum shear stress and its varying rate, the maximum shear strain and its varyingrate, the shear strain energy density and its varying rate. In view of the high inhomogeneous distribution characterof seismicity in space and time in Chinese mainland and its neighboring area, the normalized background energyvalue was given by means of normalized treatment to the earthquake energy release in the eastern and westernparts of Chinese mainland. And the comparison of the simulation result with the actual seismicity was made. Thefesults show that the simulation values can explain well the earthquake distribution character of Chinese mainlandand its neighboring area. 展开更多
关键词 tectonic stress field numerical simulation seismic activity Chinese mainland
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Magnetic constraints on the spatial distribution of seismic activity 被引量:1
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作者 Liguo Jiao Huaran Chen Mengtan Gao 《Earthquake Science》 2013年第2期125-136,共12页
The lithospheric magnetic field (LMF) in China and its surrounding are calculated using the spherical har- monic coefficients given by the NGDC-720 model. The LMF comes from the magnetization of minerals in the crus... The lithospheric magnetic field (LMF) in China and its surrounding are calculated using the spherical har- monic coefficients given by the NGDC-720 model. The LMF comes from the magnetization of minerals in the crust and in the uppermost mantle. It may, therefore, provide unique insight into lithospheric tectonic processes and mechanisms. Here, we study the geomagnetic manifesta- tion of active tectonic blocks, and find a close correlation between the LMF and seismicity. Many large faults are found to closely overlap with magnetic anomalies, or are distributed along the boundaries of magnetic anomalies. Earthquakes in these fault regions have occurred on the boundaries of magnetic anomalies, or in the transition zones between posilive and negative anomalies. We ana- lyze the components of the LMF, and the LMFs at different altitudes, finding that the vertical component, Bz at 200 kin, is the most related to seismic activity. Relevant physical mechanisms are also discussed. We propose that the stress or viscosity differences caused by temperature variations, which manifest in the LMF, may be the pre- dominant reason for the correlation between the LMF and seismic activity along large faults. 展开更多
关键词 NGDC-720 Lithospheric magneticlield China - Active tectonic block seismic activity
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The regional characteristics of seismic activity in China 被引量:1
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作者 时振梁 王健 张晓东 《Acta Seismologica Sinica(English Edition)》 CSCD 1995年第1期25-30,共6页
In this paper, the regional characteristics of seismicity of strong earthquakes in 27 seismic provinces in the wholeChina were discussed. It is divided into b kinds of regions on the basis of analyzing the earthquake&... In this paper, the regional characteristics of seismicity of strong earthquakes in 27 seismic provinces in the wholeChina were discussed. It is divided into b kinds of regions on the basis of analyzing the earthquake's annual average rate of M≥6, b-value and the maximum magnitude in history in those provinces. Among them, the seismicactivity in the eastern part of Taiwan seismic province is the highest, where the annual average rate of earthquake occurrence vM≥6 is more than 1. The second kind region includes Pamir, south and north Tianshan, Yunnan-Sichuan, west Kunlun, Himalaya and western part of Taiwan etc. 9 seismic provinces, vM≥6 are 0. 12 -0. 34. The third kind of regions contains 10 seismic provinces, such as 4 provinces in North China, northeastborder of Qingzang (Qinghai-Xizang) plateau, Gobi-Altay and the outside southeast coast province etc., wherevM≥6=0. 032-0. 08, the maximum earthquakes of Mmax≥8 were recorded in the history in most seismicprovinces of the region, only a few seismic provinces recorded Mmax=7.3-7. 5. The fourth kind of regions include 6 seismic provinces, such as the northeast China, the middle and lower reaches of the Yangtze River and South China etc., where, vM≥6=0. 01-0. 03, the largest earthquake recorded in the history is Mmax<7. Thefifth kind of regions is the one with the lowest seismic activities, Mmax=53/4 be recorded as the maximum magnitude there. The regional characteristics of the strong earthquake activity have close relationship with tectonicmovement of the surrounding plate and of the introplate block. 展开更多
关键词 strong earthquakes seismic activity China
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The Characteristics of Seismic Activity Before the Devastating Earthquake with M_W9.0 Off the West Coast of Northern Sumatra 被引量:1
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作者 Xue Yan Song Zhiping +1 位作者 Mei Shirong Liu Jie 《Earthquake Research in China》 2006年第2期118-126,共9页
The characteristics of seismic activity in different time-spatial domain before the M_W9.0 earthquake were studied. The results are as follows:The activity of the deep earthquakes in the north boundary zone of the Aus... The characteristics of seismic activity in different time-spatial domain before the M_W9.0 earthquake were studied. The results are as follows:The activity of the deep earthquakes in the north boundary zone of the Australian plate had been evidently strengthened since 1994, showing an increased frequency, magnitude and depth, especially in regards to the heterogeneous distribution of the earthquake depth (namely between 500km and 689km). Meanwhile the shallow earthquakes of M≥7.0 in the Sumatra island and its vicinity had been obviously strengthened too, and formed a strengthening area with a length of about 1000 km and width 300 km. ②The time distribution of global strong earthquakes with M≥7.0 shows that the character of anomalous seismic quiescence-activity one year before the M_W9.0 earthquake and during its active period, the strong earthquakes formed a seismic belt striking in NWW direction. At the same time, there is a seismic gap formed by earthquakes of M≥5.0 in the epicenter and its neighboring region. ③Two deep earthquakes of M≥7.0 occurred in the west and in the east of the north boundary zone of the Australian plate half year ago. It is notable that one of them occurred in the Sumatra island where no deep earthquake with M≥6.0 has occurred in the past thirty years. ④The space distribution of moderate shocks occurring three days ago exhibited a NWW-strike seismic belt along the north boundary zone of the Australian plate. ⑤The activity of volcanoes distributed in the north boundary zone of the Australian plate had been strengthened in the past 4 years, especially several months before the occurrence of the M_W9.0 earthquake. 展开更多
关键词 The Australian plate Sumatra island Sunda trench seismic gap Strengthened seismic activity seismic belt Deep earthquake activity Volcano activity
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The Deformation of Active Tectonic Blocks on the Chinese Mainland and Its Relationship with Seismic Activity 被引量:1
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作者 WangHui ZhangGuomin +1 位作者 WuYun MaHongsheng 《Earthquake Research in China》 2004年第1期54-66,共13页
Based on the hypothesis of the active tectonic blocks on the Chinese continent and its adjacent regions (both the method of the DDA on a spherical surface and the GPS survey results observed from 1991 to 2001 are used... Based on the hypothesis of the active tectonic blocks on the Chinese continent and its adjacent regions (both the method of the DDA on a spherical surface and the GPS survey results observed from 1991 to 2001 are used), the movements and deformations of each active tectonic block are calculated. The calculation results show that although the movements and deformations of active tectonic blocks in the eastern region and in the western region of China are different, active tectonic blocks in the same active tectonic block region are coherent. Then, the relative velocities of the active tectonic blocks’ boundary zones are calculated, and the relationship between current crustal motion and strong seismic activities is discussed. Earthquakes ( M S≥7 0) on the Chinese continent since 1988 all occurred on boundary zones of active tectonic blocks with high slipping speed. 展开更多
关键词 Active tectonic blocks DDA on spherical surface GPS survey results seismic activity
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Characteristics of seismic activity before several large Sumatra, Indonesia, earthquakes
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作者 薛艳 宋治平 +1 位作者 梅世蓉 马宏生 《Acta Seismologica Sinica(English Edition)》 CSCD 2008年第3期325-329,333,共6页
Two great earthquakes of MS8.5 and MS8.3 determined by the China Earthquake Networks Center (CENC) occurred successively on September 12 and 13, 2007 in the sea area to the south of Sumatra, which is another group of ... Two great earthquakes of MS8.5 and MS8.3 determined by the China Earthquake Networks Center (CENC) occurred successively on September 12 and 13, 2007 in the sea area to the south of Sumatra, which is another group of large earthquakes after MS8.7 event on December 26, 2004 and MS8.5 event on March 29, 2005. The 展开更多
关键词 seismic gap strengthened seismic activity deep earthquake activity Wadati-Benioff belt
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Identification of expected seismic activity areas by forecasting complex seismic-mode parameters in Uzbekistan
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作者 T.U.Artikov R.S.Ibragimov +1 位作者 T.L.Ibragimova M.A.Mirzaev 《Geodesy and Geodynamics》 2018年第2期121-130,共10页
In this paper, the author proposed a methodology to reveal expected seismic activation places for coming years by a complex of forecasting parameters of a seismic mode. Areas in Uzbekistan where currently observed ano... In this paper, the author proposed a methodology to reveal expected seismic activation places for coming years by a complex of forecasting parameters of a seismic mode. Areas in Uzbekistan where currently observed anomalies in various parameters of a seismic mode has been revealed. By number of displayed abnormal signs the areas has been ranked based on probability of occurrence of strong earthquakes there. It has prepared schemes of the synoptic forecast of expected seismic activation places in case of occurrence of strong earthquakes in the Central-Asian region. 展开更多
关键词 Long-term forecast of earthquakes Parameters of seismic mode seismic activity seismic gap
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Study on the Characteristics of Seismic Activity in the Interior of the Ordos Block
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作者 Xu Weijin Gao Mengtan +1 位作者 Ren Xuemei Feng Xijie 《Earthquake Research in China》 2009年第4期467-479,共13页
The temporal and spatial distribution characteristics of earthquakes in the Ordos block are studied by using historical earthquake data,instrument data of the regional seismic network around the Ordos block and the hi... The temporal and spatial distribution characteristics of earthquakes in the Ordos block are studied by using historical earthquake data,instrument data of the regional seismic network around the Ordos block and the historical felt earthquake data,and the relationship between seismicity in the Ordos block and seismicity around the Ordos block is discussed. The result shows that the Ordos block is a typical moderate-strong earthquake active region where many M_S≥5.0 destructive earthquakes have occurred. The temporal and spatial distribution of earthquakes in the Ordos block is asymmetrical. The temporal distribution of earthquakes shows a periodic characteristic and the activity of earthquakes in the southeastern Ordos block is higher than in the northwest Ordos block. The M_S≥5.0 moderate size earthquakes in the Ordos block are controlled by the M_S≥6.0 earthquake around the Ordos block. 展开更多
关键词 Ordos block seismic activity Spatio-temporal distribution
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Earthquake Disaster and Seismic Activity in China Since 1949
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作者 Dong Songsheng,Lou Baotang,Gong Shourong,Zheng Jianhua,and Li HuaSeismological Bureau of Jiangsu Province,Nanjing 210014,China 《Earthquake Research in China》 1997年第2期6-16,共11页
An outline is given in the present paper of the general situation of earthquake disasters and their temporal,spatial,and magnitude distributions in China since 1949,based on recently published Chinese disaster data.A ... An outline is given in the present paper of the general situation of earthquake disasters and their temporal,spatial,and magnitude distributions in China since 1949,based on recently published Chinese disaster data.A comparison was made between the earthquake disasters and seismic activities in China during this period.The results show that 477 disaster-causing earthquakes have occurred during this period,resulting in a death toll of 278,000 persons and the collapse of 11,000,000 rooms in residence houses.The total direct economic losses exceeded 42 billion Yuan(Chinese currency,the same below).A comparison of earthquake disasters in various regions(between East and West China,between various provinces,etc.)has shown that both correlations and significant differences exist between the spatial distributions of earthquake disasters and seismic activities in China.For example,seismic activity shows a feature of being "stronger in the West than in the East," whereas the earthquake disasters are stronger 展开更多
关键词 Earthquake Disaster and seismic activity in China Since 1949 WEST activity
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Analysis of Seismic Activity Characteristics before the Yutian M_S7.3 Earthquake,Xinjiang on February 12,2014
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作者 Nie Xiaohong Wang Qiong 《Earthquake Research in China》 2014年第4期462-474,共13页
This paper introduces the geological structure background around the 2014 Yutian Ms7. 3 earthquake area, investigates and analyzes the regime of small earthquake activity and the characteristics of regional seismicity... This paper introduces the geological structure background around the 2014 Yutian Ms7. 3 earthquake area, investigates and analyzes the regime of small earthquake activity and the characteristics of regional seismicity pattern in Xinjiang before the earthquake, and compares the characteristics of the regional seismic activity with the 2008 Yutian Ms7.3 earthquake. The results show: ① 2 ~ 3 years before the 2014 Yutian Ms7. 3 earthquake, Xinjiang was in a seismic active state with strong earthquake occurring successively, and before the 2008 Ms 7. 3 earthquake, Xinjiang was in the quiet state of moderate-small earthquakes with M3. 0 ~ 4. 0. ② Before this Yutian Ms7. 3 earthquake, the regional seismic activity showed a short-term anomaly feature, that is, seismicity of M ≥ 5. 0 earthquakes significantly increased on the Altun seismic zone and in the source area three years before the Ms7.3 earthquake, while a five year long quiescence of seismicity of M ≥4. 0 earthquakes appeared on the east of the source area in a range of about 440kin. Six months before this M7. 3 earthquake, there existed seismic gap of M3. 0 ~ 4. 0 earthquakes and near-conjugate seismic belt magnitude 3. 0 and 4. 0 in the source area. ③ The state of strong earthquake activity and the seismicity pattern of small earthquakes before this Yutian Ms7. 3 earthquake were significantly different to that before the 2008 Yutian Ms7. 3 earthquake, and this may be related to the different seismogenic environments of the two Ms7. 3 earthquakes. 展开更多
关键词 The Yutian Ms7. 3 earthquake Characteristics of seismic activity Short-termanomaly
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The forecasting efficiency under different selected regions by Pattern Informatics Method and seismic potential estimation in the North-South Seismic Zone
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作者 Weixi Tian Yongxian Zhang 《Earthquake Science》 2024年第4期368-382,共15页
In 2022,four earthquakes with M_(S)≥6.0 including the Menyuan M_(S)6.9 and Luding M_(S)6.8 earthquakes occurred in the North-South Seismic Zone(NSSZ),which demonstrated high and strong seismicity.Pattern Informatics(... In 2022,four earthquakes with M_(S)≥6.0 including the Menyuan M_(S)6.9 and Luding M_(S)6.8 earthquakes occurred in the North-South Seismic Zone(NSSZ),which demonstrated high and strong seismicity.Pattern Informatics(PI)method,as an effective long and medium term earthquake forecasting method,has been applied to the strong earthquake forecasting in Chinese mainland and results have shown the positive performance.The earthquake catalog with magnitude above M_(S)3.0 since 1970 provided by China Earthquake Networks Center was employed in this study and the Receiver Operating Characteristic(ROC)method was applied to test the forecasting efficiency of the PI method in each selected region related to the North-South Seismic Zone systematically.Based on this,we selected the area with the best ROC testing result and analyzed the evolution process of the PI hotspot map reflecting the small seismic activity pattern prior to the Menyuan M_(S)6.9 and Luding M_(S)6.8 earthquakes.A“forward”forecast for the area was carried out to assess seismic risk.The study shows the following.1)PI forecasting has higher forecasting efficiency in the selected study region where the difference of seismicity in any place of the region is smaller.2)In areas with smaller differences of seismicity,the activity pattern of small earthquakes prior to the Menyuan M_(S)6.9 and Luding M_(S)6.8 earthquakes can be obtained by analyzing the spatio-temporal evolution process of the PI hotspot map.3)The hotspot evolution in and around the southern Tazang fault in the study area is similar to that prior to the strong earthquakes,which suggests the possible seismic hazard in the future.This study could provide some ideas to the seismic hazard assessment in other regions with high seismicity,such as Japan,Californi,Turkey,and Indonesia. 展开更多
关键词 Luding M_(S)6.8 and Menyuan M_(S)6.9 earthquake Pattern Informatics Method North-South seismic Zone earthquake forecasting seismic activity pattern.
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Research on the relationship between Earth's variable rotation and global seismic activity 被引量:2
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作者 郑大伟 周永宏 《Acta Seismologica Sinica(English Edition)》 CSCD 1995年第1期31-37,共7页
Based on the time series of observational variations of the length of day (LOD) and seismic data in the world,the relations of the decadal fluctuation and seasonal variation in the Earth's rotation with global sei... Based on the time series of observational variations of the length of day (LOD) and seismic data in the world,the relations of the decadal fluctuation and seasonal variation in the Earth's rotation with global seismic activityare studied in this paper. The results suggest that there are overall correlations on temporal scale and regionaldiscrepancy on spatial scale between global seismic activity and the Earth's variable rotation, especially the seismic activity in the Eurasian seismic zone (not including southeast Asia) and the Lower California-Eastern Alaskaseismic zone correlating well with the Earth's variable rotation. According to the relations mentioned above, theobservational data of the Earth'S rotation might provide a referential basis for monitoring global seismic activity. 展开更多
关键词 Earth rotation seismic activity correlation analysis
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Plasma perturbations in the coexisting environment of VLF transmitter emission, lightning strokes and seismic activity 被引量:4
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作者 TAO Dan LIU WenLong MA YuDuan 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第5期678-686,共9页
We analyzed plasma perturbations occurring in the coexisting environment of powerful VLF transmitter emission, intense lightning strokes and strong seismic activity during pregnant period. The results suggest that ano... We analyzed plasma perturbations occurring in the coexisting environment of powerful VLF transmitter emission, intense lightning strokes and strong seismic activity during pregnant period. The results suggest that anomalous electron bursts with energy dispersion in the range of ~100–350 keV, forming the "wisp" signature, are due to cyclotron resonance of electrons with monochromatic waves from the powerful NWC VLF transmitters during nighttime. The intense broad band VLF emissions (up-going 0+ whistlers) are observed while the DEMETER satellite goes through the region of intense thunderstorm activities at mid-latitudes. However, the effects of intense lightning activity and pregnant earthquake have little impact on this kind of stable energy-dispersed electron structures, despite the fact that they are presumably two primary reasons for the particle precipitation in the ionosphere. The case studied here provides us a valuable opportunity to address the various sources triggering the anomalous plasma perturbations in the ionosphere. 展开更多
关键词 plasma perturbation electron precipitation cyclotron resonance VLF transmitter lightning seismic activity
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Impacts of seismic activity and climatic change on Chinese history in the recent millennium
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作者 FAN Jiawei JIANG Hanchao +1 位作者 XU Hongyan ZHANG Wei 《Journal of Geographical Sciences》 SCIE CSCD 2022年第11期2328-2348,共21页
General history of disasters in China suggests that China has frequently experienced two major natural disasters in its long history,one is from catastrophic earthquake events,and the other is from extreme climatic ev... General history of disasters in China suggests that China has frequently experienced two major natural disasters in its long history,one is from catastrophic earthquake events,and the other is from extreme climatic events,due to its unique active tectonic environment and climatic complexity.Although these two major natural disasters have caused great damage to human society,it remains unclear whether and how they affect Chinese dynasty alternation on decadal(emperor)timescales.Based on detailed comparisons between abrupt climatic changes,catastrophic seismic activities,and the history of Chinese dynasty alternation from 1000–2000 AD,we conclude that on decadal timescales,extreme drought(and/or flood)events could indeed significantly reduce agricultural production,cause severe food shortages and famine,and result in increases in population exile,rising food prices and inflation,and insufficient supplies for military defense,which could exceed social resilience and eventually lead to financial risks and social upheavals of the dynasties.In addition,catastrophic seismic events in the densely populated,agricultural areas of China,including the 1303 surface wave magnitude(M_(s))8.0 Hongtong earthquake,the 1556 M_(s)8.25Huaxian earthquake and the 1920 M_(s)8.5 Haiyuan earthquake,caused more than 200,000casualties and millions of victims to live in exile which was almost equivalent to the order of magnitude of those extreme climatic events-induced refugees.The secondary geological hazards related to the earthquakes(e.g.,extensive landslides and soil erosion),which could last for decades,caused more casualties and reduced food production.Furthermore,great plague spread caused by the casualties could significantly increase psychological panic among the survivors,resulting in social instability.Therefore,catastrophic seismic events could also accelerate the collapse of the dynasties(e.g.,the Ming dynasty)without immediate mitigation measures.This study indicates that catastrophic seismic activities,as well as extreme climatic events,could have great effects on the social structures and thus on the Chinese dynasty alternation on decadal timescales,which highlights the far-reaching implications of geological hazard research. 展开更多
关键词 catastrophic seismic activity extreme climatic event agricultural production social stability Chinese dynasty alternation
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Seismic activity and active faults in Huailai basin
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作者 王培德 田玉红 +1 位作者 李春来 陈运泰 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第5期125-129,共5页
SeismicactivityandactivefaultsinHuailaibasinPEIDEWANG(王培德)YUHONGTIAN(田玉红)CHUNLAILI(李春来)YUNTAICHEN(陈运泰)Instit... SeismicactivityandactivefaultsinHuailaibasinPEIDEWANG(王培德)YUHONGTIAN(田玉红)CHUNLAILI(李春来)YUNTAICHEN(陈运泰)InstituteofGeophys... 展开更多
关键词 Huailai basin seismic activity active fault digital seismic network
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Features of isostatic gravity anomaly and seismic activity in the Central Asian region
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作者 方盛明 冯锐 +3 位作者 田长征 孙桂香 王志理 李长法 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第6期105-109,共5页
In this paper, the lithospheric isostatic gravity anomaly with its distribution features in the Central Asian region (30°~70°N, 50°~140°E), according to the research of the lithospheric isostati... In this paper, the lithospheric isostatic gravity anomaly with its distribution features in the Central Asian region (30°~70°N, 50°~140°E), according to the research of the lithospheric isostatic principle, is discussed. Moreover, some primary structures and seismic activities in this region are discussed. 展开更多
关键词 isostatic gravity anomaly regional structure seismic activity the Central Asian region
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Advances in seismological methods for characterizing fault zone structure
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作者 Yan Cai Jianping Wu +1 位作者 Yaning Liu Shijie Gao 《Earthquake Science》 2024年第2期122-138,共17页
Large earthquakes frequently occur along complex fault systems.Understanding seismic rupture and long-term fault evolution requires constraining the geometric and material properties of fault zone structures.We provid... Large earthquakes frequently occur along complex fault systems.Understanding seismic rupture and long-term fault evolution requires constraining the geometric and material properties of fault zone structures.We provide a comprehensive overview of recent advancements in seismological methods used to study fault zone structures,including seismic tomography,fault zone seismic wave analysis,and seismicity analysis.Observational conditions limit our current ability to fully characterize fault zones,for example,insufficient imaging resolution to discern small-scale anomalies,incomplete capture of crucial fault zone seismic waves,and limited precision in event location accuracy.Dense seismic arrays can overcome these limitations and enable more detailed investigations of fault zone structures.Moreover,we present new insights into the structure of the Anninghe-Xiaojiang fault zone in the southeastern margin of the Qinghai-Xizang Plateau based on data collected from a dense seismic array.We found that utilizing a dense seismic array can identify small-scale features within fault zones,aiding in the interpretation of fault zone geometry and material properties. 展开更多
关键词 fault zone structure TOMOGRAPHY fault zone wave seismic activity Anninghe-Xiaojiang fault zone
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