摘要
The studies of the Quaternary sediments,the sedimentation in southern Ningxia and the Quaternary chronologic dating show many late Pleistocene sedimentary basins occurred in southern Ningxia in the late Pleistocene.The Late Pleistocene sediments in the basins are mainly featured by alluvial fan sediments,lacustrine argillaceous-silty sediments,basin-margin-slope lithofacies associations,first-terrace sediments of modern fluvial and loess sediment.The sedimentation of these basins suggests that the late Pleistocene sedimentary basin was controlled by regionally tectonic extension,which indicates that an obvious tectonic extension affected the southern Ningxia in the northeastward growth and uplift of the Tibetan Plateau,and provides a sedimentological evidence for the phasal uplift of the Tibetan Plateau.