DISTRIBUTION REGULARITY AND DEVELOPMENT BACKGROUND OF LANDSLIDES AT EDGE OF LOESS TABLE LAND FROM BAOJI TO CHANGXING

This paper is based on the predecessors' research and is aided with investigation and prospection at field. It analyzes the distribution regularity and development background of landslides at the edge of the loess table lands from Baoji to Changxing. It proves the following five points. (1)The scales of the landslides decrease gradually from super large to large and middle,even small.(2)Landslides are at these sites where Ⅲ terrace or both Ⅲ and Ⅱ terrace disappeared.(3)Development of landslides mainly has three periods: early stage of late Pleistocene epoch,early stage of Holocene epoch and last stage of Holocene epoch.(4)The eastward tilting movement with activity difference of the lithosphere in the west of Weihe river basin resulted in the physiognomy pattern of tablelands with distinct altitude differences. Then it controlled the development regular change of scales of the landslides. The northward movement of Weihe river and intense riverside eroding induced the concentrated development of landslides at the edge of the tablelands in different periods.(5)The intense human engineering movements are the main inducing factor of new landslides or revival of old landslides in late stage of Holocene.