b'AEGC 2023Short abstractschanges in the sedimentary environments. To succeed infor target anomalies associated with unconsolidated subsurface hydrocarbon exploration in such areas, it is necessary tostrata or voiding.conduct an integrated geological study to deeper understand tectonic, magmatic, and sedimentary evolution of the region.The first sparse 3D hardrock seismic survey at Olympic Our study comes from the Browse Basin which is a typicalDampassive continental margin located in the Australian Northwest Shelf. The exploration of the Jurassic and Cretaceous sandstoneJared Townsend 1, Heather Schijns1, Kathy Ehrig2, David reservoirs of this basin has been active in the past decadesHaddow2 and Max Shawcross2where over 20 hydrocarbon discoveries were made. Although1 BHP Group Limited the hydrocarbon resource is highly promising, severely faulted2 BHP Olympic Damreservoirs and distribution of unpredictable igneous rocks are recognised as one of the major risks for both exploration andThe first sparse 3D hardrock seismic survey at BHPs Olympic field development activities. Dam (OD) mine was acquired during June to August of 2022. OD is located in South Australia and is the flagship deposit for Our study aimed to investigate the basin-wide record ofIron-Oxide Copper Gold (IOCG) style mineralisation. OD is one Mesozoic tectonic and igneous events by integrating multipleof the largest known copper deposits and the single largest geoscience data including regional 2D and 3D seismic surveys,uranium deposit in the world, with mineralisation hosted in data from exploration/appraisal wells, and regional gravity- a hydrothermal breccia unconformably overlain by ~350 m magnetic data. This project discusses the basin architecture, theof flat-lying Neoproterozoic to Cambrian sediments. The distribution of intrusives and extrusive rocks, the petrologicalresearch topic is the acquisition of sparse 3D hardrock seismic characteristics of igneous and sedimentary rocks, and theirdata on more than 200 line km of existing roads and tracks at correlation to seismic facies. We also interpreted a successiona busy mining operation and the immediate learnings from of Mesozoic palaeo-environmental maps of the Browse Basin,preliminary results.which illustrate transitions of igneous rock distribution and types through geological time. The outcome of this studyHardrock seismic has been adapted from extensive use in will contribute on future exploration and field developmenthydrocarbon exploration and has the benefit of maintaining planning in the Browse Basin. high spatial resolution down to several kilometres of depth. Advances in technologies over the last decade for acquisition, processing, and interpretation of land seismic are mitigating the MASW and microgravitya novel approach tochallenges of using this technique for resource characterisation investigating Karstic features in a large tailings storagein hardrock terrains. Effective application of hardrock seismic at facility. OD will aid accelerated resource characterisation and improve the targeting of deep drillholes beneath the current known Aaron Tomkins and Benjamin Thomas resource.Multi-channel Analysis of Surface Waves (MASW) is a non- The process of acquiring seismic data on a large mining destructive seismic method which uses the elastic propertiesoperation is unknown to most members of this industry. A of subsurface materials to determine the subsurface structure.broad range of stakeholders from the General Mine Managers By analysis of the dispersive properties of varying frequenciesdown to specific Area Owners and Supervisors were identified, from a single seismic source, shear-wave velocity (Vs) andengaged, educated, and convinced that we could safely and associated geotechnical parameters can be determined.effectively achieve this survey. Environmental and Cultural Microgravity is a potential field technique used to accuratelyHeritage engagements commenced over a year before the record localised variations in the earths gravitational field.survey and Traditional Owners were invited to ensure that BHPs The variations in gravitational readings are caused by densityrigorous land use standards were being honoured.contrasts of the rocks and sediments beneath the reading location. Both methods are therefore an indicator of differentThis adaptation of modern-day hardrock 3D seismic techniques subsurface units and through careful interpretation, anover a metalliferous orebody represents the first of many more accurate image of the subsurface can be inferred. Althoughapplications for BHP to aid resource characterisation and the both have been used independently for karstic investigations,targeting of deep drillholes.they have not been combined for a large-scale geotechnical investigation and used to constrain the overall 3DA review of the geophysical response of Codelcos geotechnical model.Ministro Hales mine.This paper presents an alternative way of using seismic and gravity investigations with the primary objective to targetHector Verdejo 1 Jimena Vargas2, Terry Ritchie3 and Peter unconsolidated subsurface strata or voiding, within limestoneRowston3terrains. The way data is collected and combined within this1 Geophysical Resources and Services paper is specifically designed and applicable for Tailings Storage2 CODELCO Facilities. The paper introduces the reader to automated GPS3 Geophysical Resources and Services Pty.corrected MASW data collection, while handling large datasets in excess of 85 000 shots. The paper also covers 3D inversionHistorically, Codelco carried out an intensive exploration and display of the MASW data, and how modelled data canprogramme in the proximity of the well-known porphyry, be interrogated to use results and findings to plan a GravityChuquicamata. A suite of geophysical data including gravity, campaign over anomalous areas. Finally, the paper will outlineairborne magnetics and electromagmetics (EM), time domain how all datasets can then be used to constrain final 3D modelsEM (TDEM), and induced polarisation (IP), were recorded and 147 PREVIEW FEBRUARY 2023'