Gippsland Basin 3D forward modelling in Badlands

Summary The Gippsland basin geological history is modelled using the Badlands software constrained by a realistic 3D structural and stratigraphic model built in Petrel. The aim is to assess and calibrate the theoretical tectonic and sedimentary models using empirical data for a rift basin. The theoretical models are used to assess and measure the relative effect of significant variables for sedimentary basins, including climate, extension, subsidence, uplift, erosion and sedimentation. The modelling results indicate several insights for the Gippsland Basin. The initial paleo-topography at ~145 Ma was an extensive highland area. The Early Cretaceous paleo-environment was intracratonic, with sediment transport from east to west, and at some stage included an inland sea. The Mid Cretaceous uplift caused emergence of the entire basin, substantial regional erosion and changed the basin architecture. Subsidence associated with Tasman Sea rifting formed the Central Deep and flipped the fluvial paleo-drainage system towards the east. Latrobe Group sediments filled the basin being progressively transgressed by rising sea level to flood most areas by the Oligocene. The models simulate the progradation of the carbonate shelf sediments, sub-marine channels and anticlines over the basin since then.