Taking the Huaihe to the Nvshanhu segment of the Tanlu( Tancheng-Lujiang) fault zone as the main research target to explore whether there has been new activity since the late Quaternary,and based on the interpretation...Taking the Huaihe to the Nvshanhu segment of the Tanlu( Tancheng-Lujiang) fault zone as the main research target to explore whether there has been new activity since the late Quaternary,and based on the interpretation of remote sensing images and repeated surface investigations,we excavated trenches at the sections where the tectonic landform is significant,identified and recorded the deformation patterns of the fault and analyzed the activity behavior. Samples of new activity and deformation were collected and oriented slices were ground based on the samples ' original state to make the micro structural analysis and demonstration. All of the above research shows very clear linear tectonic geomorphology along the fault,three trenches across the fault zone all revealed new deformation traces since late Quaternary. The latest stratum dislocated by the fault is the late Quaternary and Holocene. The main slip mode is stick slip,as represented typically by fault scarps,wedge accumulation,the faults and the filled cracks and so on. In general,it shows the characteristics of brittle high-speed deformation and belongs to the prehistoric earthquake ruins. The above understanding was confirmed partially by microscopic analysis. In addition,the similarities and differences and the possible reasons for the characteristics of the latest activities of the Tancheng-Lujiang fault zone in the north and south of the Huaihe River regions are also discussed in this paper.展开更多
基金jointly funded by the Anhui provincial geological public-welfare project“New Activities of Quaternary and Medium Velocity Structure Exploration and Evaluation for Key Sections of the Tan-Lu Fault Zone(the Anhui segment)”(2015-g-25)the project of“3-D Seismic Section Model and Earthquake Prediction Research in the Tanlu Fault Zone”,China Earthquake Administration(TYZ20160101)
文摘Taking the Huaihe to the Nvshanhu segment of the Tanlu( Tancheng-Lujiang) fault zone as the main research target to explore whether there has been new activity since the late Quaternary,and based on the interpretation of remote sensing images and repeated surface investigations,we excavated trenches at the sections where the tectonic landform is significant,identified and recorded the deformation patterns of the fault and analyzed the activity behavior. Samples of new activity and deformation were collected and oriented slices were ground based on the samples ' original state to make the micro structural analysis and demonstration. All of the above research shows very clear linear tectonic geomorphology along the fault,three trenches across the fault zone all revealed new deformation traces since late Quaternary. The latest stratum dislocated by the fault is the late Quaternary and Holocene. The main slip mode is stick slip,as represented typically by fault scarps,wedge accumulation,the faults and the filled cracks and so on. In general,it shows the characteristics of brittle high-speed deformation and belongs to the prehistoric earthquake ruins. The above understanding was confirmed partially by microscopic analysis. In addition,the similarities and differences and the possible reasons for the characteristics of the latest activities of the Tancheng-Lujiang fault zone in the north and south of the Huaihe River regions are also discussed in this paper.
