Australian Landscapes
Australian Landscapes provides an up-to-date statement on the geomorphology of Australia. Karst, desert, bedrock rivers, coasts, submarine geomorphology, biogeomorphology and tectonics are all covered, aided by the latest geochronological techniques and remote sensing approaches. The antiquity and enduring geomorphological stability of the Australian continent are emphasized in several chapters, but the cutting-edge techniques used to establish that stability also reveal much complexity, including areas of considerable recent tectonic activity and a wide range of rates of landscape change.
Links to the biological sphere are explored, in relation both to the lengthy human presence on the continent and to a biota that resulted from Cenozoic aridification of the continent, dated using new techniques. New syntheses of glaciation in Tasmania, aridification in South Australia and aeolian activity all focus on Quaternary landscape evolution.
This major synthesis of Australian geomorphology is dedicated to Professor John Chappell (The Australian National University) and Professor Martin Williams (University of Adelaide).
Tectonic geomorphology of Australia
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Published:January 01, 2010
Abstract
The Australian continent is actively deforming in response to far-field stresses generated by plate boundary interactions and buoyancy forces associated with mantle dynamics. On the largest scale (several 103 km), the submergence of the northern continental shelf is driven by dynamic topography caused by mantle downwelling along the Indo-Pacific subduction system and accentuated by a regionally elevated geoid. The emergence of the southern shelf is attributed to the progressive movement of Australia away from a dynamic topography low. On the intermediate scale (several 102 km), low-amplitude (c. 100–200 m) long-wavelength (c. 100–300 km) topographic undulations are driven by (1) anomalous, smaller-scale upper mantle convection, and/or (2) lithospheric-scale buckling associated with plate boundary tectonic forcing. On the smallest scale (101 km), fault-related deformation driven by partitioning of far-field stresses has modified surface topography at rates of up to c. 170 m Ma−1, generated more than 30–50% of the contemporary topographic relief between some of Australia's highlands and adjacent piedmonts, and exerted a first-order control on long-term (104–106 a) bedrock erosion. Although Australia is often regarded as tectonically and geomorphologically quiescent, Neogene to Recent tectonically induced landscape evolution has occurred across the continent, with geomorphological expressions ranging from mild to dramatic.