QUATERNARY PERIGLACIAL STAGES OF THE SONGLIAO PLAIN
Sun Jianzhong (Institute of Geological Sciences, Jilin Province)
Periglacial structures are widely distributed at Songliao plain in the North- eastern Region of China.Their common forms are:ice wedges,involutions and solifluctions.According to stratigraphical and chronological data,The periglacial stages have been divided as following: 1.Baitushan periglacial stage,characterized by the involutions developed in Baitushan formation.Paleomagnetic dating 3.4—3.0—1.7m.y.B.P. 2.Huangshan periglacial stage,characterized by the involutions and ice wedges developed in Huangshan formation.Paleomagnetic dating 1.2～1.0— 0.75m.y.B.P. 3.Donggang periglacial stage,characterized by the involutions developed in Donggang formation.Thermo-luminescent dating:0.2—0.15m.y.B.P. 4.Guxiangtun periglacial stage,characterized by the ice wedges and involutions developed in Guxiangtun formation and by the cold-loving fauna and flora:Mammuthus-Coelodonta fauna and dark coniferous forest flora and permafrost fauna in the same formation.C~(14) dating:70,000—10,000 years B.P. 5.Tailitu periglacial stage,characterized by the solifluction found near Tailitu village.It might occur in early Holocene. 6.Modern periglacial stage,characterized by the ice wedges and involu- tions filled by black soil.This stage might be corresponding to the little ice age.