Study of Geomorphic Environment on Fractal Characteristics -A Case Study on the Continental Divide of Australia

Aneesha Balakrishnan and Scott Rice-Snow
Department of Geological Science, Ball State University, Muncie, Indiana 47304, USA

The geomorphic environment of a region may be determined by many parameters such as climate, relief, bed rock characteristics, slope, rainfall and tectonics. This present study seeks to determine the effect of geomorphic environment on the complexity of the Australian continental divide trace, as depicted in map view. Australia has experienced geological forces such as tectonic uplift of mountain ranges in early history. With its present location being in the middle of the tectonic plate, it does not show active volcanism, although it experiences minor earthquakes. The degree of irregularity of the Australian continental divide trace can be measured by fractal dimension as calculated by divider method. In order to study the influence of geomorphic processes, the continental divide forming along the Eastern Highland known as Great Dividing Range has been divided into 2 segments north and south. The fractal dimension (D) found for the north part is 1.07 and for the south part is 1.08. Focused examination at coarse resolutions shows an even stronger contrast in D values. The continental divide in the north segment runs along the Great Artesian Basin in the interior Central Lowlands while the south segment runs along the crests of coastal mountain ranges and series of high plateaus. The increase in D value from north to south corresponds to an increase in local relief near the divide. The difference in placement of the drainage divide relative to Australia’s high escarpment may affect the irregularity characteristics of the continental divide.

AAPG Search and Discover Article #90087 © 2008 AAPG/SEG Student Expo, Houston, Texas