Large potential field anomalies can be observed in the Marla region of northern South Australia, and have been used to define the northern limit of the Gawler Craton. The subject project’s aim was to model the plausible source(s) for each of those anomalies in order to try to explain their existence. Within this region, the poorly known basement is buried beneath Neoproterozoic to Recent cover sediments of the eastern Officer, Arckaringa and Eromanga basins, so the first step taken in the analysis was to constrain the geometry of the basins. The outcropping geology, drillhole data and seismic reflection profiles were then used to map out the depth to crystalline basement, and depth to the base of the Arckaringa Basin fill sequence. In the model presented here, the depth to basement horizon shows, in particular, the complex geometry of the Munyarai Trough, which forms a foreland to the uplifted Musgrave Block; the prominent features of the Marla Overthrust Zone and Ammaroodinna Ridge, which were uplifted after the deposition of Cambrian to Silurian sedimentary rocks; and lastly, the major tectonic element of the Middle Bore Fault Zone, which was last active during deposition of the Arckaringa Basin and the Wintinna Trough. Note that the geometries of the included faults have been interpreted based on seismic data, with the result that the faults are often poorly imaged, especially parts of the Middle Bore Fault Zone. Also shown in the 3D model are isosurfaces of petrophysical properties (density and magnetic susceptibility) used for constraining UBC-GIF inversions. To the south of the Middle Bore Fault Zone, potential field anomalies are small and are often shallowly sourced, and the magnetic and gravity anomalism is broadly coincident. To the north of the Middle Bore Fault Zone, a large high density body is inferred, whereas below the Ammaroodinna Ridge, and extending a little to the south-east below the Manya Trough, is an offset magnetic anomaly. The largest magnetic susceptibility body observed appears to dip to the north-west, which is consistent with the general dip of structures imaged by the GOMA seismic line (Korsch et al., 2010). The authors conclude that the major potential field anomalies in this northernmost region of the Province have a basement source, and represent a lower crust having significantly different properties to those of the southern Nawa Domain, the area to the south of the Middle Bore Fault Zone, and also the Musgrave Block further to the north. This distinctive geophysical region may indicate a major geological boundary, although the significance and age of such a boundary are unclear. However, rocks studied from across the entire region all show evidence of Kimban aged granulite to amphibolite grade metamorphism or magmatism (Fanning et al., 2007; Payne et al., 2008).