Morphometry of lunette dunes in the Tirari Desert, South Australia

Abstract

Abstract Morphometry and formation processes are key research problems in the study of aeolian sandy landforms. Based on morphometric parameters inferred from satellite images and the calculation of the drift potential (DP), we examined general characteristics of lunette dunes in the Tirari Desert, South Australia, along with their morphometry and formation processes to determine how this landform type initially formed and its relationship to surrounding linear dune distribution. Results show that the morphometric parameters of lunette dunes and connective lake systems exhibit moderate correlations. It suggests that the morphology of these dunes is controlled by the lakes. Spatially, the lunette dunes present regular arrangement, and the strike of their alignment are approximately in accordance with the linear dunes. The calculated DP implies that the lunette dunes developed under a low-wind-energy environment, which is a wind regime similar to that required for the formation of the surrounding linear dunes. Even though, the resultant DP demonstrates that the summer wind should be responsible for the growth of the lunette dunes. However, accompanied with the repeated drying of lakes and even its disappearance during the dune development process, it not only contributes to the development of lunette dunes but also promotes their transformation to linear dunes.