关键词: 全新世, 左阶羽列, 右旋走滑

Abstract: The fault scarp of the Tangto fault is 36 km long,1 to 3m high,striking NE15?. Its east side has been uplifted. The fault scarp in ground surface approximately is along the fault face that consists of Cretaceous sandstone and Archaean gneiss. Twelve gullies which strike nearly EW were dislocated in right lateral mode by three left-stepping echelon secondary faults in 1.1km distance,in the vicinity of Juquan village,where the gullies are contorted with right angle or their lower and upper reaches are offset. The horizontal dislocation is 3-25m. The biggest is in middle,the smaller is in either end of the fault in one of the three secondary fault. In a place along the fault,it has been discovered that the peat which has a few square metre has been uplifted. Its position is about 2.0m to the bottom at present. It is considered that the peat was the early sediment in the pool along the fault scarp. The 11G dating of the peat is 3681 a B.P. and two faulting can be shown. One occurred before 3681a probably and the other is the dextral strike slip faulting occurring in last 3681a. If creep-slip is not in consideration,two earthquake events would have occurred since Middle-Late Holo-cene.

Key words: Holocene, Left-stepping echelon, Dextral shrike-slip