b'AEGC 2023Short abstractsbeing modelled with a 3D inversion programme. A cooperative(IOCG) and iron sulfide-copper-gold (ISCG) deposits. Monazite joint inversion is being conducted between the magnetics andchemistry has recently been shown to be useful in exploration the EM, and where available, surface, geotechnical and boreholefor hematite-group IOCG deposits in the Gawler Craton, information is being incorporated. South Australia, where the monazite preserves elevated concentrations of light rare earth elements (Ce and La) relative to monazite that has grown in other geological settings (e.g., Uranium exploration in the Athabasca Basin using low- metamorphic monazite, monazite associated with shear zones). noise airborne gravity gradient data. However, the applicability of the IOCG monazite geochemical Darren Burrows and Adam Smiarowski exploration criteria outside of the Gawler Craton and to ISCG systems has yet to be investigated. This study will present Xcalibur monazite chemistry from selected IOCG and ISCG deposits in the Cloncurry District, Queensland, to attempt to define if broad The Athabasca Basin, northern Saskatchewan, Canada, ismonazite geochemical exploration criteria are applicable to renowned for the largest, high-grade uranium deposits in theIOCG/ISCG exploration. Monazite chemistry has been analysed world. Historically, most of the deposits have been discoveredusing the same methodology of earlier studies in the Gawler within the Basin with as much as 700 m of overlying sandstoneCraton so that direct comparison of geochemical exploration cover. A new generation of shallow, basement-hosted depositscriteria can be made.are currently being explored for near the margins and outside of the Basin. We will show examples of low-noise airborne gravity gradient data, and how it is sensitive to zones of hydrothermalIntegrated regional velocity model building through alteration which could be indicative of uranium fertile fluidFWI and well-constrained tomography for exploration systems. The gravity gradient data was combined with structuraland fields development- Wheatstone Australia.interpretations of airborne magnetic to highlight prospective drill targets. Saidamiri Besheli 1 Talal Esmaiel1, Aishah Al-Toum1, Peter Thomas2 and Manish Agarwal2The hydrothermal fluids result in extensive argillic alteration halos that commonly form around uranium deposits. The1 KUFPEC alteration halos are the main target for the airborne gravity2 Applied Geoscience Pty Ltdsurveys. However, gravity methods will only be effective at mapping potential alteration zones in areas where the Basin isThe Julimar gas field is located in the Carnarvon Basin, NW shallow, or where the Athabasca Group has been eroded andof Australia. Julimar and Brunello fields supply 20% gas to basement rocks are exposed. A new generation of shallow,the Wheatstone LNG project. Julimar Phase 2 development basement-hosted deposits are currently being explored for near(JDP-2) campaign was successfully completed in 2021. In the margins and outside of the Basin. preparation for the JDP-3 and exploration activities, KUFPEC have successfully initiated and completed Integrated A case study of the Baseload Energy Hook block will be shown.Regional Velocity Modeling for an area of 3000 m2. FWI The ACKIO uranium discovery will be highlighted using thevelocity models from five 3D seismic surveys along with 80+ magnetic and the gravity data to understand the structural andwells were integrated for velocity modeling in this study. A hydrothermal aspects of the this target respectively. final merged velocity model was built through two iterations of the leading-edge technology of Well Constrained Monazite chemistry for IOCG and ISCG exploration. Tomography (WCT), supported by detailed well ties analysis.Travis BatchCaroline Tiddy , Adrienne Brotodewo , DavidIn this part of the Carnarvon Basin, velocity model and depth 1 1 1Giles , Glen Littleand Antonio Belperio conversion are deemed to be challenging due to presence of 1 2 2complex water bottom topography, heterogeneous Tertiary 1 Mineral Exploration Cooperative Research Centre (MinEx CRC) carbonates and complex overburden channels and canyons. 2 Demetallica The study was designed to reduce uncertainty associated with seismic interpretation, depth conversion, prospect generation, Within Australia and around the globe, the rate of discoverywell placement and resources estimation. Dip-steered filters of economic mineral deposits has been declining since mostwere used to guide the tomography for the first time in this easily accessible surface and shallow deposits have alreadyarea. WCT is a ray-based/inversion approach to tie well data to a been exploited. To combat the risk of drilling, techniquesvelocity model and is based on tomographic principles in which which value-add to drilling are being developed. One suchdepth errors are converted to time errors along zero-offset rays technique is using the geochemistry of resistate mineral phasesto minimise the error in the velocity model.(e.g. monazite, zircon) to indicate the presence of nearby mineralisation. To quantitatively measure uncertainties around the velocity model, two iterations of WCT velocity model building were Monazite is an accessory mineral with a general formulaperformed. The uncertainties associated with the first iteration AXO 4(where A = light REE, U, Th, etc.; X = P, rarely As) and isof WCT were quantified through Blind Well Testing at 22 wells. commonly used for geochronology. It is highly susceptibleThe second iteration of WCT with integration of 86 wells was to alteration by hydrothermal fluids, which can change theperformed to create the final velocity model.chemistry of monazite to reflect the conditions it experienced during alteration and the composition of the hydrothermalThe results/insights from the final integrated velocity model fluids. have provided an excellent basis for the depth conversion, prospect maturation, well placement and resources estimation Hydrothermal fluids are a common component of variousover KUFPECs producing and exploration assets in the mineralising systems, including iron oxide-copper-goldWheatstone area.85 PREVIEW FEBRUARY 2023'