|
Lianwang Chen, Institute of Crustal Dynamics, CEA (China)
Hong Li, Institute of Crustal Dynamics, CEA (China)
Yujiang Li, Institute of Crustal Dynamics, CEA (China)
|
|
Based on related data of seismogeology, geophysics, focal mechanism solution and GPS data, a finer 3-D finite element model of active faults in Guangzhou area has been built up to numerically simulate the motion modes nowadays and the Coulomb failure stress rates of four active faults in Guangzhou area on the given boundary condition. The numerical results are as follows: 1) the motion mode of Guangzhou-Conghua fault is compressional thrusting, in the southern segment, vertical slip rate is 0.0465 mm/a, horizontal slip rate is 0.0024 mm/a, the ratio is 19.4; in northern segment, vertical slip rate is 0.0426 mm/a, horizontal slip rate is 0.002 mm/a, the ratio is 21.3. 2) the motion mode of the west segment of Shougouling fault is right-lateral strike slipping but the east segment is right-lateral strike-slipping dominantly and thrusting accompanying, in the western segment, vertical slip rate is 0.0018 mm/a, horizontal slip rate is 0.0178 mm/a, the ratio is 0.1; in eastern segment, vertical slip rate is 0.0265 mm/a, horizontal slip rate is 0.0462 mm/a, the ratio is 0.6. 3) the motion modes of the west and east branches of Zhujiangkou fault are both left-lateral strike-slipping and thrusting as well as, in the western branch, vertical slip rate is 0.0055 mm/a, horizontal slip rate is 0.262 mm/a, the ratio is 0.2; in eastern branch, vertical slip rate is 0.007 mm/a, horizontal slip rate is 0.0255 mm/a, the ratio is 0.3. 4) the average Coulomb failure stress cumulative rates per year of Guangzhou-Conghua fault (4345 Pa/a) and the east segment of Shougouling fault (1330 Pa/a) are evidently higher than that of the west segment of Shougouling fault (621 Pa/a) and the west branch (584 Pa/a) and the east branch (613 Pa/a) of Zhujiangkou fault.
|
