In this paper, rock mass is regarded as anisotropic clastic units and the partial differential equation of subsidence has been testified. The solution about homogeneous anisotropy has been obtained. The existence of i...In this paper, rock mass is regarded as anisotropic clastic units and the partial differential equation of subsidence has been testified. The solution about homogeneous anisotropy has been obtained. The existence of inflection point offset in subsidence formula has been proved. Lastly, the relevant influence factors about the offset of inflection point have been simply discussed.展开更多
Goafs are threats to safe mining.Their imaging effects or those of other complex geological bodies are often poor in conventional reflected wave images.Hence,accurate detection of goafs has become an important problem...Goafs are threats to safe mining.Their imaging effects or those of other complex geological bodies are often poor in conventional reflected wave images.Hence,accurate detection of goafs has become an important problem,to be solved with a sense of urgency.Based on scattering theory,we used an equivalent offset method to extract Common Scattering Point gathers,in order to analyze different scattering wave characteristics between Common Scattering Point and Common Mid Point gathers and to compare stack and migration imaging effects.Our research results show that the scattering wave imaging method is more efficient than the conventional imaging method and is therefore a more effective imaging method for detecting goafs and other complex geological bodies.It has important implications for safe mining procedures and infrastructures.展开更多
The paper introduces the steps and methods of multi-approach, multi-level exploration of buried faults in thick Quaternary sediment regions by taking the test exploration of the Yinchuan active fault as example. Based...The paper introduces the steps and methods of multi-approach, multi-level exploration of buried faults in thick Quaternary sediment regions by taking the test exploration of the Yinchuan active fault as example. Based on the comprehensive analyses of previous data, we choose the Xinqushao Village of Xingqing District of Yinchuan City as the test site for the comprehensive exploration. Firstly, we adopted shallow seismic investigation with group intervals of 10m, 5m and lm to gradually trace layer by layer the master fault of the Yinchuan buried fault from a deep depth to a shallow depth where drilling could be used. Then, with composite geological profile drilling, we determined the precise location and dip angle of the fault. The drilling show the buried depth of the upper offset point is 8.3m. Finally, large-scale trenching revealed that the actual buried depth of the upper offset point of the fault is 1.5m from the ground surface and there are paleoearthquake events of 5 stages. Combined with the preliminary result of corresponding sample age, we conclude the Yinchuan buried fault is a mid to late Holocene active fault.展开更多
文摘In this paper, rock mass is regarded as anisotropic clastic units and the partial differential equation of subsidence has been testified. The solution about homogeneous anisotropy has been obtained. The existence of inflection point offset in subsidence formula has been proved. Lastly, the relevant influence factors about the offset of inflection point have been simply discussed.
基金Financial support for this work,provided by the Key National Project(No.2008ZX05035)the State Science and Technology Support Program,the National Natural Science Foundation of China (Nos.40574057,40874054,40804026)the State Basic Research and Development Program of China(No.2007CB209406)
文摘Goafs are threats to safe mining.Their imaging effects or those of other complex geological bodies are often poor in conventional reflected wave images.Hence,accurate detection of goafs has become an important problem,to be solved with a sense of urgency.Based on scattering theory,we used an equivalent offset method to extract Common Scattering Point gathers,in order to analyze different scattering wave characteristics between Common Scattering Point and Common Mid Point gathers and to compare stack and migration imaging effects.Our research results show that the scattering wave imaging method is more efficient than the conventional imaging method and is therefore a more effective imaging method for detecting goafs and other complex geological bodies.It has important implications for safe mining procedures and infrastructures.
基金The research was jointly sponsored by the National Development and Reform Commission of China under the project of"Experimental Exploration of Active Fault in Urban Area"(20041138)by National Natural Science Foundation of China (40234040)
文摘The paper introduces the steps and methods of multi-approach, multi-level exploration of buried faults in thick Quaternary sediment regions by taking the test exploration of the Yinchuan active fault as example. Based on the comprehensive analyses of previous data, we choose the Xinqushao Village of Xingqing District of Yinchuan City as the test site for the comprehensive exploration. Firstly, we adopted shallow seismic investigation with group intervals of 10m, 5m and lm to gradually trace layer by layer the master fault of the Yinchuan buried fault from a deep depth to a shallow depth where drilling could be used. Then, with composite geological profile drilling, we determined the precise location and dip angle of the fault. The drilling show the buried depth of the upper offset point is 8.3m. Finally, large-scale trenching revealed that the actual buried depth of the upper offset point of the fault is 1.5m from the ground surface and there are paleoearthquake events of 5 stages. Combined with the preliminary result of corresponding sample age, we conclude the Yinchuan buried fault is a mid to late Holocene active fault.
