b'AEGC 2021Short abstractsThe interest on Induced Polarization in AEM data (AIP) hasExploration through transported cover is a fundamental significantly increased in recent years, both within the researchchallenge for the mineral exploration industry in Australia. This community and in the industry. However, the inversion of AIPcontext is driving the redefinition of approaches and strategies data is particularly ill-posed, especially when spectral modelling,of mineral exploration.such as Cole-Cole modelling, is used. The present study investigates the Forrestania area, located In this study we present a novel approach for model spacein the Yilgarn Craton, Western Australia as a case study to definition, in which the AIP inversion parameters are defined oncombine geochemical landscape evolution and pattern model meshes which do not coincide with the forward meshessimilarity analysis techniques. In the research area within used for data modelling: the link between model and forwardForrestania, dioritic basement and saprock are overlain by meshes is obtained interpolating the model mesh parametersthe saprolitic package of (1) a lower mottled unit; (2) a middle into the forward mesh discretization. This spatial decouplingsmectite/nontronite unit; and (3) an upper kaolinitic unit. allows for defining the AIP model parameters, e.g. the Cole- Lacustrine cover, which is between 6 and 15 m thick, overlies Cole ones, on different model meshes, for instance one for eachthe basement and saprolitic package, and the depth to inversion parameter. In this way, it is possible to define the spectralbasement varies from 40 and ~85 m.parameters, like the time constant and the frequency exponent in the Cole-Cole model, on meshes much coarser than the resistivityThe saprock and the lower/mottled saprolite unit preserve the and chargeability ones, both vertically and horizontally, withbasement geochemical footprint. However, metallic vertical a significant improvement in parameter resolution. However,dispersion processes in the area are not efficient due to the the novel approach is completely general, and allows forpresence of three geochemical barriers/gradients (Fig. 1A). These incorporating any kind of prior information through the definitionbarriers/gradients are (1) the smectite/nontronite and kaolinitic of parameters in problem-taylored meshes. units, (2) the lacustrine and fluvial sediment transported cover, and (3) the soil. In the basement, Au correlates with As (r2 = 0.90); Examples of the novel inversion approach are presented onin the lower saprolite unit Au correlates with Ba (r2 = 0.91), and in different AIP surveys, highlighting the improvements in modelthe soil Au is associated with carbonates.resolution, conversion rate and dependence on the starting model when compared to standard inversion approaches. The landscape regimes in the area are both erosional and depositional. Overall, Au mines and prospects in the region 264: Recognition of igneous rocks encountered in wellsare located within erosional landscape regimes, and the main in the Carnarvon Basin: implications for drilling andAu soil anomalies are also located on the slopes of landscape petroleum systems erosional landforms. Pattern similarity analysis was conducted based on the evaluation of the relationship between the Mr Michael Curtis 1, A/Prof Simon Holford1, Dr Mark Bunch1 andmineralisation and covariate data (digital elevation model, Dr Nick Schofield2 flatness, structures, geology, airborne magnetics, and soil geochemistry). Standard geological data integration and data 1 Australian School of Petroleum and Energy Resources,analytics have highlighted three prospective areas for Au University of Adelaide, Australia exploration in the Forrestania Greenstone Belt with respect to 2 Department of Earth Sciences, University of Aberdeen, Scotland the best Au drilling intersection.The Carnarvon Basin formed during the separation of Greater India and Australia in the Mesozoic. Rifting was associated with266: Geochemical signatures and critical metal the generation of large volumes of melt (possibly related to acontents of key deposit types in the Mount Isa hotspot beneath the Cape Range Fracture Zone), which wasProvince, Queensland, Australiaemplaced into the upper crust of the Exmouth Plateau and Exmouth Sub-basin from the late Jurassic until breakup in theDr Vladimir Lisitsin 1, Ms Courteney Dhnaram1 and Dr Matthew early Cretaceous. Despite the magmatic system spanning 50Valetich1000 km2 across the Exmouth Plateau and Exmouth Sub-basin, few wells have intersected igneous rocks. Of those that have, we find1 Geological Survey of Queenslandthat the majority of igneous rock penetrations are unintentional. Geological Survey of Queensland (GSQ) has undertaken a large-In this contribution, we evaluate the impact of igneous rocks onscale programme of systematic geochemical and mineralogical drilling operations, and petroleum systems, for each well knowncharacterisation of key deposit types and mineral systems in the to have passed through igneous rocks in the Carnarvon Basin. Mount Isa Province, with a particular focus on their critical metal contents. This work contributed to and expanded multi-year 265: Geochemical landscape evolution and patterncollaborative projects between GSQ and CSIRO. The programme similarity analysis at tenement scale for goldencompassed: acquisition of representative drill core and ore samples from multiple deposits of different types (donated by exploration in Forrestania, Yilgarn craton exploration and mining companies); hyperspectral and XRF Dr IgnacioGonzalez-Alvarez 1, Dr Oscar Rondn-Gonzlez2,scanning of continuous core; multi-element geochemistry Mrs Tania Ibrahimi1, Dr Ian Lau1, Ms Monica LeGrass1, Mr Deanon multiple samples from each deposit (from ore to distal Goodwin3, Dr Vasek Metelka1, Mrs Tenten Pinchand1 and Msalteration footprints and background). Target deposit types (and Carmen Krapf4 deposits) include: Iron-oxide copper-gold (IOCG - Ernest Henry, E1, Mount Elliott - SWAN, Eloise, Little Eva, Kalman, Osborne and 1 CSIRO Starra), sediment-hosted Zn-Pb-Ag (Mt Isa Zn-Pb, George Fisher, 2 Snowden Group Dugald River, Cannington), sediment-hosted (sensu lato) Cu (Mt 3 Classic Minerals Ltd. Isa Cu, Capricorn Cu, Lady Annie) and phosphorite (Phosphate 4 GSSA Hill, Ardmore).AUGUST 2021 PREVIEW 108'