Activity Features and Slip Rate of the Lingwu Fault in Late Quaternary

The Lingwn fault is in the eastern boundarv of the southern section of Yinchuan graben. It has a close relation to seismicity in the Lingwu-Wuzhong region. Few researches have been aone. In this paper, on the basis of the data obtained from field investigation, the activity features in Late Quaternary have been discussed. The vertical displacement and its slip rate have been also estimated. The fault is 48km in length, being divided into 3 segments according to geological and topographical characteristics. The last rupture along its northern and middle segments was occurred in late of Late Pleistocene or early Holocene while that along the southern segment was occurred in middle Holocene. The vertical slip rate is estimated as 0.23 - 0.25mm/a since about 66 ka B. P. based on the vertical displacements of terraces I, II and III and their ages.