PRESENT CRUSTAL DEFORMATION AND STRAIN CHARACTERISTICS OF DATONG BASIN
1) College of Geology Engineering and Geomatics, Chang’an University，Xi’an 710054
2)Key Laboratory of Western China’s Mineral Resources and Geological Engineering,
Ministry of Education, Xi’an 710054
3) Second Crust Monitoring and Application Center, CEA, Xi’an 710054
Abstract Based on the high precision GPS monitoring data from 2006 to 2010 of China Crustal Movement Observation Network, the present crustal threedimensional velocity fields of Datong basin are obtained. Mainwhile by making use of strain analysis of graphical elements combined with significant test method, the present crustal strain parameters and its distribution features are also obtained, then the tectonic origin of ground fissures in Datong is analyzed. The results show that the present crustal movement of Datong basin demonstrates an overall horizontal extension and internal rift subsidence. The interior basin demonstrates overall tensile strain with the NW-SE direction, the most significant strain is at the northwest of the basin, with its value reaching 1.9×10-6/a, and this area is also the typical crack of Datong basin. The ground fissures in Datong basin is controlled by fault activities under the regional tensional stress field with the NW-SN direction.
