1. Potential Field Interpretation of the Capricorn Orogen JAMES GOODWIN Worms, forward modelling and 3D inversion

2. Potential Field Interpretation of the Capricorn Orogen Purpose Investigate regional-scale crustal architecture Relationship between Pilbara/Capricorn/Yilgarn Compare with seismic line interpretation Interpretation Techniques Image processing Multiscale edge detection (worms) Forward modelling 3D inversion (unconstrained)

3. Potential Field Interpretation of the Capricorn Orogen Seismic line 10GA-CP1 Hamersley Ashburton Magnetics RTP Surface Geology Nanjilgardy Fault

4. Potential Field Interpretation of the Capricorn Orogen Leake Springs Metamorphics = correlative of Upper Wyloo Group (Cawood and Tyler 2004; Sheppard et al., 2007) Seismic line 10GA-CP1 Ashburton Fm Hamersley Group Collier Edmund Group Leake Springs Metamorphics

5. Potential Field Interpretation of the Capricorn Orogen Hamersley Ashburton Bouguer Gravity Gravity Worms Magnetics Worms Seismic line 10GA-CP1 Karra Well Fault (SW dipping) Baring Downs Fault

6. Potential Field Interpretation of the Capricorn Orogen MAGNETIC INVERSION GRAVITY INVERSION GRAVITY MAGNETICS RTP Baring Downs Fault Hamersley Group Off line effects 0 30 60 Depth (km) 0 mGals -100 mGals 1000 nT -1000 nT 2.7 2.6 2.7 2.6 3.2 2.9 3.2 / 0.10 2.9 2.8 2.67 2.7 2.8 2.6 Mantle Lower Crust Granite-Greenstone Bandee UWG LWG N S Hamersley Fortescue Group

7. Potential Field Interpretation of the Capricorn Orogen Seismic line 10GA-CP2 Collier Moorarie Supersuite Durlacher Supersuite Moogie Metamorphics Edmund Group Leake Springs Metamorphics Lyons River Fault ? contact Surface Geology Magnetics RTP Magnetics Worms Gravity Worms Bouguer Gravity Durlacher Supersuite Cardilya Fault

8. Potential Field Interpretation of the Capricorn Orogen Bandee Seismic Province Glenburgh Terrane MAGNETIC INVERSION GRAVITY INVERSION GRAVITY MAGNETICS RTP Bandee Seismic Province Glenburgh Terrane Edmund Group Durlarcher Moorarie -10 mGals -50 mGals 500 nT -500 nT 2.85 2.77 2.9 3.2 2.8 2.9 2.8 / 0.02 2.8 2.67 2.6 2.9 2.67 2.6 N S UWG LWG Mantle Leake Springs Metamorphics 2.7 / 0.05 Edmund Group Lyons River Fault

9. Potential Field Interpretation of the Capricorn Orogen Seismic line 10GA-CP3 Errabiddy Shear Zone Narryer Terrane Dalgaringa Supersuite Surface Geology Magnetics RTP Magnetics Worms Gravity Worms Bouguer Gravity

10. Potential Field Interpretation of the Capricorn Orogen BIF 74257 Seismic line 10GA-CP3 10GA-CP3

11. Potential Field Interpretation of the Capricorn Orogen Seismic line 10GA-CP3

12. Potential Field Interpretation of the Capricorn Orogen Narryer Terrane Glenburgh Terrane Errabiddy Shear Zone MAGNETIC INVERSION GRAVITY INVERSION

13. Potential Field Interpretation of the Capricorn Orogen Key Findings Forward models suggest the seismic line interpretation is consistent with potential field data. Hamersley Group has the potential to extend as far south as the Edmund Basin Magnetic anomalies attributed mainly to the Hamersley Group, Leake Springs Metamorphics and BIF 74257 Yilgarn-Capricorn boundary is south-dipping