This dataset is the basin wetlands throughout the area of the Simpson Desert that lies above the Northern Territory (NT) portion of the Great Artesian Basin (groundwater basin). Some polygons of some wetlands types (e.g. swamps, clay pans, waterholes) occur within a broader floodplain area. In these cases the floodplain is mapped as a distinct polygon that overlaps other wetland polygons. Drainage lines are not delineated in this mapping, although some drainage lines are within the areas inundated in large events. Some waterhole wetlands within drainage lines were mapped but not systematically across the area. The mapping covers most of the NT part of the Simpson Desert and includes the Pedirka Basin (geological basin). In some areas, small clay pans were not mapped for this product either because they were smaller than the minimum size (<900m2) or because there was no record of past inundation in Landsat satellite imagery. In eight locations there is a very high density of small clay pans (<900m2) and these have been mapped as point features in an accompanying dataset.