The results of a study undertaken to produce depth estimates to the top of magnetic anomaly sources are presented within this report. The area of interest is located within the present-day preserved footprint of the ~500 Ma Delamerian Orogenic Belt, and is bounded by the current Geological Survey of South Australia (GSSA)'s Section 15 Gazetted Area boundary. There are some sparse outcrops of pre-Delamerian Orogeny rocks along the subject area's boundary in the west and north, but mostly these older, largely unknown rocks are now covered by sedimentary basins of variable thickness. This study forms part of GSSA’s involvement with delivering the third of three MinEx CRC research programs, namely the National Drilling Initiative (NDI). Data collected from eleven past government and private company airborne magnetic surveys have been investigated, and results are being provided as both a combined coverage set and individual sets created for each survey's coverage. A total of 437 depth estimates have been produced for single causative magnetic anomalies located within the boundaries of the eleven airborne surveys. For the combined coverage result set, the final grid interpolation distance was 250 m, and the produced contour interval was 50 m. As noted by Foss (cf. RB 2020/00018 re. the GCAS Region 9B magnetic data modelling), the data in the grid has been greatly smoothed by the gridding process, and therefore is a poor representation of the true basement surface. This is due to the large grid interpolation distances compared with the scale of local complexity of the true geological surface. Results are presented as magnetic basement depth grids and contours. All calculations were completed using the magnetic inversion tool contained within ModelVision, a proprietary software package marketed by Tensor Research. The methodology used was based on the “sweet-spot” traverse inversion depth-estimation technique described by Foss in appendix 5 of this report.