b'ASEG newsCommitteesof the basin contains a substantialHolford, S., Schofield, N., MacDonald, J., Duddy, I.allowing for extensive and repeated Jurassic igneous sequence, with Grace-1and Green, P., 2012. Seismic analysis of igneousmineralising fluid mobilisation along specifically confirming a thicknesssystems in sedimentary basins and their impactsthe flanks of the dome. Theres also of at least 1100 m. The uppermoston hydrocarbon prospectivity: examples froma significant density and magnetic section consists of 100 to 450 m ofthe southern Australian margin. The APPEAsusceptibility contrast between the basaltic tabular lava flows, which areJournal,52, https://doi.org/10.1071/aj11017. metabasalt and the metaturbidites characterised by low GR wireline logMillett, J.M., Wilkins, A.D. et al., 2016. The geologythat make potential field methods values and repeating high-low cyclicof offshore drilling through basalt sequences:an ideal vector for imaging buried patterns of density and sonic wireline logUnderstanding operational complicationsportions of the structure.values. The lower section is composedto improve efficiency. Marine and Petroleum of felsic igneous rocks (with relativelyGeology, 77, 1177-1192, https://doi.org/10.1016/A set of potential field anomalies higher GR values) are followed by alteredj.marpetgeo.2016.08.010. analogous to Magdala occur along-igneous rock interbedded with LowerPlanke, S., Symonds, P.A., Alvestad, E. andstrike within the structural trend of the Jurassic sedimentary rocks, extendingSkogseid, J. 2000., Seismic volcanostratigraphyStawell Corridor, where the Murray Basin several hundred meters in thickness. of large-volume basaltic extrusive complexes onsedimentary cover obscures outcrop rifted margins. Journal of Geophysical Research:and geochemical pathfinders (Figure 1). The findings from the Maginnis-1A/ST2Solid Earth, 105, 19335-19351, https://doi.org/A handful of the anomalies have been and Warrabkook-1 wells suggest that the10.1029/1999jb900005. confirmed by drilling to be metabasalts western outboard area is characterisedSchofield, N., Holford, S. et al., 2017. Regionalwith gold intervals at prospective grades. by a basaltic sequence exceeding 400 mmagma plumbing and emplacementThe Wildwood and Lubeck dome targets in thickness, with limited development ofmechanisms of the Faroe-Shetland Sill Complex:fall within the North Stawell Minerals sedimentary reservoirs. These substantialimplications for magma transport and petroleumtenement, where an AGG survey was basaltic sections led to drilling challenges;systems within sedimentary basins. Basinacquired in 2021 to better target the Maginnis-1A/ST2 faced extremely lowResearch, 29, 41-63, https://doi.org/10.1111/ structures. Lateral boundaries for rates of penetration, required fourbre.12164. Wildwood and Lubeck are well imaged tri-cone bits to penetrate a 483-meterSenger, K., Millett, J., Planke, S., Ogata, K.,by the AGG, but their cross-sectional interval. Meanwhile, Warrabkook-1Eide,C.H., Festy, M., Galland, O. and Jerram,geometries are largely unconstrained by experienced significant mud losses andD.A., 2017. Effects of igneous intrusions on thedirect drillhole intersections. On the other subsequent ballooning effects. petroleum system: a review. First Break, 35. hand, the geometry and structural style of Watson, D., Schofield, N., Maguire, A., Telford, C.,Magdala has been thoroughly constrained Failure to accurately predict theMark, N., Archer, S. and Hardman, J., 2020. Raidersby mine mapping and drilling, but was only distribution and characteristics of igneousof the Lost Mud: the geology behind drillingcovered by sparse gravity measurements.rock formations is a significant factor in theincidents within the Balder Formation around lack of successful exploration outcomesthe Corona Ridge, West of Shetland. PetroleumFor this project, we collected ground in the outboard basin. Variety in rock typeGeoscience, 26, 110-125, https://doi.org/ gravity measurements in profiles across and physical properties complicates thedoi:10.1144/petgeo2018-060. the Magdala, Wildwood and Lubeck correlation between well interpretationsZahedi, M.K. and MacDonald, S., 2018. Volcanics:domes to get a comparable dataset for and seismic data, hindering preciseA Commonly Underestimated part of Petroleumforward modelling their geometries predictions of igneous intervals andExploration. ASEG Extended Abstracts, 2018, 1-6. according to their potential field signals, potential sandstone reservoir locations.at enough resolution and sensitivity This study underscores the importance ofRF22M02 University of Melbourne,to attempt to resolve the buttress comprehending igneous rock properties,MScstudent Tom McNamara (supervisorstructures on the dome surfaces that connecting them to seismic data, andDr Mark McLean). controlled fluid flow and mineralisation. evaluating their distribution in a regionalThe profiles were planned with variable context. Addressing these aspects willCharacterisation of metavolcanicstation spacing, up to 25 m apart at enhance the understanding of igneousmegaclast structures within thethe crests of the domes to target the rock complexities, ultimately improvingMoyston Fault hanging wall mlangefine-scale structures, and down to 100 exploration efforts in magma-rich basins.(Moornambool Metamorphic Complex),m apart beyond the flanks of the domes The study offers valuable insights intowestern Victoria: Insights from potentialto ascertain the regional trend. A total the Browse Basin, providing lessonsfield modelling and machine learning. of 397 new gravity measurements were and implications for future petroleumStawell Gold Mine extracts oretaken spanning 16 km.exploration, field development, and thefrom mineralised zones along theThe gravity profiles were forward feasibility of carbon capture and storageflanks of the metamorphosed,modelled in 2D cross-sections, together in this region. structurally buttressed metabasalticwith TMI data extracted from a Geological Magdala Dome, an uptorn megaclastSurvey of Victoria regional compilation. A References about 4 km long and 1 km acrosssection extracted from the existing mine sitting in a tectonic melange. Themodel at Magdala was tested against the Curtis, M.S., Holford, S.P., Bunch, M.A. andcompetency contrast between theobserved gravity, and while it matched Schofield, N.J., 2022. Seismic, petrophysical andMagdala Volcanics metabasalt andthe character of the main Magdala petrological constraints on the alteration ofthe surrounding metaturbiditeDome anomaly, there were complexities igneous rocks in the Northern Carnarvon Basin,that makes up the Moornamboolin the signal that were unaccounted Western Australia: implications for petroleum exploration and drilling operations. The APPEAMetamorphic Complex controlledfor. Incorporating surface drilling and Journal, 62, 196-222, https://doi.org/10.1071/ the local faulting and shear planesmapping constraints, the profiles were aj21172.during Victorias orogenic history,forward modelled to account for the FEBRUARY 2024PREVIEW 11'