Objective The 2014 Ludian Mw6.1 earthquake in Yunnan occurred in a mountainous area with complex tectonics and topography, which caused serious damage as well as co-seismic landslides of an unusual large scale. Becau...Objective The 2014 Ludian Mw6.1 earthquake in Yunnan occurred in a mountainous area with complex tectonics and topography, which caused serious damage as well as co-seismic landslides of an unusual large scale. Because the suspected seismogenic faults on the surface, distribution of aftershocks and focal mechanism solutions are not consistent, it remains difficult to determine what is the real causal fault or seismogenic structure for this event. Actually, it may imply the complicity of the seismic source at depth. In addition, the distribution of the co- seismic landslides also exhibits some diffusion that is different from general eases, likely associated with the seismic focus structure.展开更多
Objective Nowadays, high-resolution remote sensing technology has brought new changes to surveys of earthquakes, and the quantitative study of seismic faults based on this technology has become a trend in the world(Ba...Objective Nowadays, high-resolution remote sensing technology has brought new changes to surveys of earthquakes, and the quantitative study of seismic faults based on this technology has become a trend in the world(Barzegari et al., 2017). An Mw 7.2 earthquake occurred in Yutian of Xinjiang on the western end of the Altyn Tagh fault on March 21 st, 2008. It is difficult to access this depopulated zone because of the high altitude and only 1–2 months of snowmelt. This study utilized high-resolution展开更多
The mechanism study of earthquake occurrence is of great importance to the society,for earthquakes are one of the most damaging natural catastrophes[1,2].Studies show that an earthquake produces a net reduction of str...The mechanism study of earthquake occurrence is of great importance to the society,for earthquakes are one of the most damaging natural catastrophes[1,2].Studies show that an earthquake produces a net reduction of stress on the fault,yet the stress does not disappear,but is transferred to nearby regions,changing the stress state and seismicity of surrounding faults.展开更多
In this paper,we give a brief introduction to the proposal and development history of the earthquake magnitude concept. Moment magnitude MWis the best physical quantity for measuring earthquakes. Compared with other m...In this paper,we give a brief introduction to the proposal and development history of the earthquake magnitude concept. Moment magnitude MWis the best physical quantity for measuring earthquakes. Compared with other magnitude scales used traditionally,moment magnitude is not saturated for all earthquakes,regardless of big and small earthquakes,deep and shallow earthquakes,far field and near field seismic data,geodetic and geological data,moment magnitude can be measured,and can be connected with wellknown magnitude scales such as surface wave magnitude MS. Moment magnitude is a uniform magnitude scale,which is suitable for statistics with wide magnitude range.Moment magnitude is the preferred magnitude selected by the International Seismological community,and it is preferred by the departments responsible for publishing seismic information to the public. Moment magnitude is a uniform magnitude scale,which is suitable for statistics with wide magnitude range. Moment magnitude is a preferred magnitude for international seismology,it is preferred by the agency responsible for providing information about earthquakes to the public. We provide all formulas used in the calculation of moment magnitude,and the calculation steps in detail. We also analyzed some problems and rules to solve these problems by using different formulas and numerical value calculation steps.展开更多
基金supported by the National Natural Science Foundation of China(grant No.41572194)the Institute of Geology,China Earthquake Administration(grant No.IGCEA1604)the National Key Basic Research Program of China(grant No.2013CB733205)
文摘Objective The 2014 Ludian Mw6.1 earthquake in Yunnan occurred in a mountainous area with complex tectonics and topography, which caused serious damage as well as co-seismic landslides of an unusual large scale. Because the suspected seismogenic faults on the surface, distribution of aftershocks and focal mechanism solutions are not consistent, it remains difficult to determine what is the real causal fault or seismogenic structure for this event. Actually, it may imply the complicity of the seismic source at depth. In addition, the distribution of the co- seismic landslides also exhibits some diffusion that is different from general eases, likely associated with the seismic focus structure.
基金supported by the National Natural Science Foundation of China (grants No. 41461164002 and 41631073)
文摘Objective Nowadays, high-resolution remote sensing technology has brought new changes to surveys of earthquakes, and the quantitative study of seismic faults based on this technology has become a trend in the world(Barzegari et al., 2017). An Mw 7.2 earthquake occurred in Yutian of Xinjiang on the western end of the Altyn Tagh fault on March 21 st, 2008. It is difficult to access this depopulated zone because of the high altitude and only 1–2 months of snowmelt. This study utilized high-resolution
基金financially supported by the National Key Research and Development Program of China(201YFC1500302)the National Natural Science Foundation of China(41674106).
文摘The mechanism study of earthquake occurrence is of great importance to the society,for earthquakes are one of the most damaging natural catastrophes[1,2].Studies show that an earthquake produces a net reduction of stress on the fault,yet the stress does not disappear,but is transferred to nearby regions,changing the stress state and seismicity of surrounding faults.
基金the Monitoring Task of Department of Earthquake Monitoring and Prediction,China Earthquake Administration(2018)Technical Support and Effect Analysis of New Magnitude National Standard Implementation.
文摘In this paper,we give a brief introduction to the proposal and development history of the earthquake magnitude concept. Moment magnitude MWis the best physical quantity for measuring earthquakes. Compared with other magnitude scales used traditionally,moment magnitude is not saturated for all earthquakes,regardless of big and small earthquakes,deep and shallow earthquakes,far field and near field seismic data,geodetic and geological data,moment magnitude can be measured,and can be connected with wellknown magnitude scales such as surface wave magnitude MS. Moment magnitude is a uniform magnitude scale,which is suitable for statistics with wide magnitude range.Moment magnitude is the preferred magnitude selected by the International Seismological community,and it is preferred by the departments responsible for publishing seismic information to the public. Moment magnitude is a uniform magnitude scale,which is suitable for statistics with wide magnitude range. Moment magnitude is a preferred magnitude for international seismology,it is preferred by the agency responsible for providing information about earthquakes to the public. We provide all formulas used in the calculation of moment magnitude,and the calculation steps in detail. We also analyzed some problems and rules to solve these problems by using different formulas and numerical value calculation steps.
