b'AEGC 2023Short abstractsAustralia-wide downhole DAS array for observationalworld to focus on the spectral shift in the composition of seismology. alunite from potassium-rich (K-alunite) to sodium-rich (Na-alunite) to vector the mineralisation. In recent years, spectral Roman Pevzner1, Konstantin Tertyshnikov1, Sinem yavuz1, Pavelresolution of these instruments have increased due to demand Shashkin1, Valeriya Shulakova2 and Boris Gurevich by correlating data sets from other remote sensing technologies 1 Curtin Universitylike hyperspectral imaging. This study focuses on using ultra 2 CSIRO high resolution to characterise K-alunite from Na-alunite by identifying additional features not seen with lower resolution Downhole seismic acquired with distributed acoustic sensorsspectrometers, an application that can be used in the future for (DAS) provides a unique opportunity to record genuinelybetter understanding of mineralised zones.broadband data with a frequency range varying from sub-mHz to several kHz. As such, downhole DAS can be used to detectUsing computer vision and drill core photography to and track local microearthquakes caused by fluid injection into a reservoir, analyse natural seismicity or look at infra-low frequenciesautomate geological logging workflows and improve such as oceanic microseisms. Most existing studies use localorebody knowledge.single-well installations or multi-well installations spread over a few km. In 2020-2022, we acquired continuous DAS data in threeNathanael Pittawaydifferent locations across Australia: Otway International Test CentreDatarock Pty Ltdin Victoria, National Geosequestration Laboratory (NGL) training well at the Curtin University Campus in Perth and Harvey-3 well,Core logging is often carried out by many geologists with located 120 km south of Perth in Western Australia. At Otway, wedifferent levels of skill and experience who collectively do acquired more than 830 days of data in five ~1.5 km deep wellsnot interpret and record their observations in the same way instrumented with DAS cables behind the casing and a ~1 kmover the life of a project. This has traditionally led to logged long helically wound cable deployed at 1 m depth, was acquired.datasets often being viewed as inconsistent and lacking any real The NGL training well DAS facility comprises a 900 m deep wellauditability.with a fibre-optic cable cemented behind the casing and a ~2.5 km of dark fibre in communication cables running around theComputer vision techniques address some of these issues by campus. More than 300 days of data available for this location.extracting geological information from drill core imagery with Harvey-3 is an abandoned well drilled as a part of South West CCSsignificantly improved consistency and detail compared to Hub appraisal and characterisation programme. The fibre-opticcurrent manual logging. Veins are one of the most neglected cable was installed during P&A operations inside the sacrificialand poorly logged datasets due to their complexity, scale, and tubing employed to cement the well, transforming the meant- volume throughout an ore body. Consequently, logged vein to-be-lost asset into a permanent sensor array. Over a monthdata often comprises subjective estimates or averages and sub-of passive DAS recording is available. The data contains sharedsampled detail that is inconsistently logged.records of regional (for the wells within a state) and teleseismicUsing computer vision-based techniques, we analyse a large events and other components of the ambient wavefield. Datadatabase of traditional RGB core photography to generate analysis shows differences in the performance of those sites andnew types of high-resolution vein data including vein type various cable deployment options for observational semiology. classifications at 5 cm resolution and vein morphology segmentations at the pixel scale. These novel vein data are then Overview of the Barrow Island land seismic acquisitioninterrogated in 3D to demonstrate how these high-resolution and 4D processing of the first Gorgon CO2 time-lapsevein characteristics can provide new geological insights and monitor survey. improve ore body knowledge.This work aims to demonstrate the advantages of computer vision logging techniques based Paul Phythian, Marcel Rive, Chris Walton and Leigh Scoby-Smith on their ability to create new types of logging data with improved consistency. Computer vision logging also benefits Chevron geologists by allowing them to move beyond routine and The Gorgon CO 2Carbon Capture and Storage (CCS) projectrepetitive work, and focus more on higher-level technical tasks.on Barrow Island is an integral part of Chevrons Green House Gas (GHG) reduction targets and Lower Carbon objective. ThisGeophysical responses of Devoncourt Prospect - a presentation gives an overview of the land acquisition andgranite hosted iocg in North-West Queensland, 4D processing of the 2021 seismic monitor survey carried outAustralia.for reservoir surveillance and characterisation of the injected CO 2 . This is the first time-lapse seismic imaging of at least sixNikhil Prakash and JamesAldermansurveys that are planned over the life of the carbon capture and sequestration project that is designed to minimise the impactRio Tinto Explorationto the environment on the Barrow Island Class A Nature Reserve.The Devoncourt prospect is a Rio Tinto Exploration (RTX) project located 60 km south-west of Cloncurry. The project Alunite characterisation with ultra high resolution SWIR. is targeting an IOCG system beneath ~200 m of post Lori Shelton Pieniazek Proterozoic cover. Following a review of known mineral prospects, and publicly available drill core from the area, RTX Alunite characteristics and composition are used as a goodapplied for EPM26800 covering two prominent magnetic indicator of gold potential in an epithermal system. Fieldanomalies in the Wimberu Granite. Detailed ground gravity portable spectrometers have been widely used around thewas completed, and a coincident ~1 mgal gravity anomaly FEBRUARY 2023 PREVIEW 130'