b'Education matters Dina Chu, University of Tasmania:delineate stratigraphically controlleda better understanding of the fracture Geophysical Characterisation of the Pinezones of disseminated pyrrhotite formednetworks in the Hawkesbury Sandstone Creek Gold Deposit. by thermal metamorphism of originaland how fractures may contribute to the pyritic beds. The regional magneticflow pathways between underground anomaly pattern provides a basis forand groundwater systems. It also aims to detailed structural interpretation. determine the possibility of an alternate theory for regional deformation, in the Petrophysical measurements indicateform of detachment folding.that geophysical methods are likely to be ineffective for mapping local lithologicalThis study was conducted on the or stratigraphic variations at Pine CreekSouthern Highlands of New South or for direct delineation of mineralisation.Wales, with a key focus on three rock However, downhole wireline loggingoutcrops at Yanderra. Photogrammetry suggests that some mineralised intervalsmodels were developed which were then may be associated with elevateduploaded to a 3D geological software electrical conductivity and chargeabilityprogram (IPM-MOVE) for geological and this possibility should be furtherinterpretation. The established mesh The Pine Creek area, Northern Territoryevaluated. Structural interpretation ofsurfaces were interpreted to develop contains structurally controlledthe regional aeromagnetic data hascross-sections and quantitative results, orogenic gold mineralisation withinhighlighted antiformal regions underwith a particular focus on fracture quartz-sulphide veins that are typicallyshallow cover that may be prospectivelength and spacing at each outcrop. The concentrated in hinges of antiforms.for Pine Creek style mineralisation. acquired fracture measurements, along Limited geophysical prospecting has beenwith three test apertures were used undertaken in this environment and theRebecca Chapple, University ofto develop a conceptual model of the potential effectiveness of geophysicalWollongong: 3D geological mappingporosity and hydraulic conductivity of methods for discrimination of goldof fracture networks in the Hawkesburyfracture networks within each outcrop.mineralisation, rock types and stratigraphySandstone and their implications to has not previously been tested. groundwater flow. The calculated porosity of the fractures Petrophysical measurementsin the Hawkesbury Sandstone, based conducted on drill core from theon observed fracture length, ranged Gandys and International prospectsfrom 0.001-0.011% with three different characterise the properties ofapertures, while the conceptual model mineralisation and host stratigraphy,based on fracture spacing ranged from and can be used to assess the likely0.001-0.022%. The expected hydraulic efficacy of large-scale geophysicalconductivity of fractures ranged from survey methods. Quantitative and0.040 m/day to 15.64 m/day. The depth qualitative interpretation of regionalto detachment was calculated to be aeromagnetic data here provide aapproximately 325 m, which indicates a basis for interpretation of the structuraldetachment layer is possibly within the framework in the Pine Creek area. Illawarra Coal Measures.Drill core petrophysical measurementsThroughout history, there has beenFractures are a clear host to fluid cannot be used to reliably discriminateextensive research performed on themovement through rock outcrops. local lithological and stratigraphicHawkesbury Sandstone, however, littleLongwall mining can cause movement variations at Pine Creek or to identifyhas been done within academic literatureon existing fractures due to subsidence, mineralised rocks. Rock physicalon the fracture networks throughoutand thus, have implications for the properties have been homogenisedit, specifically on their influence onmovement of groundwater throughout primarily by the effects of thermalgroundwater flow and storage. Thethem. This could have the potential metamorphism and alteration. Northwest- regional deformation is also believed toto affect recharge within aquifers trending regional magnetic anomaliesbe due to basement control, with littlethroughout the Sydney Basin and should are interpreted, on the basis of modelling,research performed on alternate theoriesbe considered in future fracture studies to be concordant to bedding and likelyof deformation. This study aims to developand mining operations.45 PREVIEW DECEMBER 2021'