Fangjun Li

3D modelling of flexural isostatic deformation

Modelling of the isostatic loading of the earths crust in three dimensions is a difficult problem due to the length scales involved, the lack of scalability of the underlying equations and the slow convergence of the solution under conventional techniques. In this paper, a new method to solve the three-dimensional (3D) flexure equation has been developed. The long-standing challenge in numerically modelling flexural isostasy at large scale and high rigidity is addressed. The program is capable of modelling both local and regional isostatic compensation. Compared with other schemes, the isostatic model presented here is more robust and computationally efficient.

Multigrain seabed sediment transport modelling for the south-west Australian Shelf

With increasing concerns about climate change and sea-level rise, there is a need for a comprehensive under- standing of the sedimentary processes involved in the erosion, transport and deposition of sediment on the continental shelf. In the present paper, long-term and large-scale seabed morphological changes on the south-west Australian con- tinental shelf were investigated by a comprehensive sediment transport model, Sedsim. The investigated area covers the continental shelf and abyssal basins of the south-western region. The regional seabed is sensitive to environmental forces and sediment supply, and most terrigenous sediment carried down by major rivers is trapped in inland lakes or estuaries. Only a small fraction of fine-grain sediment reaches the continental shelf. The simulation has also confirmed that the Leeuwin Current and high-energy waves play the most important roles in regional long-term seabed evolution. Although the numerical implementation only approximates some forcing and responses, it represents a significant step forward in understanding the nature of potential long-term seabed change as a response to possible climate change scenarios. The 50-year forecast on the seabed morphological changes provides a reference for the management of coastal and offshore resources, as well as infrastructure, in a sustainable way.