Periglacial landforms and deposits of Tasmania

• Main Author: Colhoun, Eric A.
• Other Authors: The University of Newcastle. Faculty of Science & Information Technology, School of Mathematical and Physical Sciences
• Format: Article in Journal/Newspaper
• Language: English
• Published: Academy of Science of South Africa 2002
• Subjects: glacial landforms; Pleistocene; stratigraphic geography; Tasmania; periglacial processes; Ice; permafrost
• Online Access: http://hdl.handle.net/1959.13/33904

Only limited parts of Tasmania were glaciated during the late Pleistocene. The extra-glacial regions exhibit many landforms and deposits that were developed at least partly by periglacial processes. Block streams, block fields and screes are well developed above 900 m on the dolerite plateaux of central and eastern Tasmania, while slope deposits of angular clasts occur on the siliceous rocks of western mountain areas. Extensive fossil solifluction deposits extend down to c. 500 m in central Tasmania, whereas modern frost-creep terraces and solifluction lobes occur only locally above 900 m in poorly vegetated areas. Active sorted polygonsmay occur on bare areas down to 600 m, and contemporary snowpatch erosion occurs above 1000 m. Fossil ice-pushed shoreline features occur on some lakes on the dolerite Central Plateau, while stabilized terrestrial sand dunes occur at lower altitudes in theMidlands and east. Few of these landforms and deposits are yet well dated, and many may have been formed during several cold stages of the Pleistocene. There is little evidence for Pleistocene permafrost below 1000-1200 m on the island.