Academic literature on the topic 'Reservoirs Victoria Gippsland'

One of the main risks associated with the underground storage of CO2 is the possibility of leakage from the reservoir to the surface. Among the most likely pathways for CO2 migration are permeable fault systems and highly fractured caprocks. It is thus important to develop a detailed understanding of geometrical characteristics of fault systems to assess the long-term storage and reactivation potential of fault dependent reservoirs. This extended abstract describes the results from a detailed structural analysis of the Rosedale Fault System (RFS) in the Gippsland Basin, Victoria, which is undergoing assessment for CO2 storage, using high-fidelity 3D seismic data. The RFS is a long-lived fault system that has experienced significant reactivation since the late Miocene and continued activity on this fault. Conventional structural mapping has been supported by seismic attribute analyses using a dip-steering cube. The coupling of seismic attribute analysis with fault displacement analysis has enabled the geometry of the RFS to be defined and to delineate associated damage zone. This extended abstract's analysis shows that the RFS is an anastomosing normal fault system that displays lateral changes in the degree of late Miocene-onwards reverse reactivation, which has affected the Latrobe Group and older units. This analysis has also revealed an extensive polygonal fault-system confined to post-Top Latrobe (Eocene) sediments, showing that this component of the stratigraphy is structurally decoupled from the older sedimentary section. This extended abstract concludes by assessing the roles that both the RFS and the polygonal fault system play in fluid migration in the western Gippsland Basin.

One of the Victorian Government's policies in the oil and gas area is to enhance the benefits to the State in the energy sector by assessing the nature and extent of the petroleum resources. To evaluate the production capacity of developed and undeveloped gas fields, a comprehensive study was commissioned by the DITR in 1988. The first step in a study of this type is to check the accuracy of the depth maps, to see if they adequately describe the reservoir geometry. Raypath modelling, using the Advanced Interpretation Mapping System (AIMS ? Version III), was carried out by Geophysical Services International (GSI), Sydney, on a number of selected profiles over the Snapper, Marlin-Turrum, Barracouta, Kipper and Emperor fields for the DITR. Input data for the models were extracted from the operator's maps. The software simulates the normal incidence raypaths (or wave theory solution) for all shotpoints, and from this information it generates gather records and/or synthetic seismic profiles. By comparing the model data with those from data acquisition, processing and interpretation, it was possible to check the validity of the interpretation of the reservoir's geometry. This modelling work showed that the synthetic data were comparable with the acquisition and processing data, confirming that the depth maps (tied to well control) produced by the operator using its proprietary software are adequate and most likely to represent subsurface configuration of the reservoirs.

The Torquay Sub-basin lies to the south of Port Phillip Bay in Victoria. It has two main tectonic elements; a Basin Deep area which is flanked to the southeast by the shallower Snail Terrace. It is bounded by the Otway Ranges to the northwest and shallow basement elsewhere. The stratigraphy of the area reflects the influence of two overlapping basins. The Lower Cretaceous section is equivalent to the Otway Group of the Otway Basin, whilst the Upper Cretaceous and Tertiary section is comparable with the Bass Basin stratigraphy.The Torquay Sub-basin apparently has all of the essential ingredients needed for successful hydrocarbon exploration. It has good reservoir-seal pairs, moderate structural deformation and probable source rocks in a deep kitchen. Four play types are recognised:Large Miocene age anticlines, similar to those in the Gippsland Basin, with an Eocene sandstone reservoir objective;The same reservoir in localised Oligocene anticlines associated with fault inversion;Possible Lower Cretaceous Eumeralla Formation sandstones in tilted fault blocks and faulted anticlines; andLower Cretaceous Crayfish Sub-group sandstones also in tilted fault block traps.Maturity modelling suggests that the Miocene anticlines post-date hydrocarbon generation. Poor reservoir potential and complex fault trap geometries downgrade the two Lower Cretaceous plays.The Oligocene play was tested by Wild Dog-1 which penetrated excellent Eocene age reservoir sands beneath a plastic shale seal, however, the well failed to encounter any hydrocarbons. Post-mortem analysis indicates the well tested a valid trap. The failure of the well is attributed to a lack of charge. Remaining exploration potential is limited to the deeper plays which have much greater risks associated with each play element.

Environmental context. Eutrophication can lead to the production of harmful algal blooms and is one of the world’s most serious water quality issues. Phosphorus is potentially the limiting macro-nutrient in fresh, estuarine and some marine waters. Consequently, it plays a crucial role in determining the ecological status of many aquatic ecosystems. Considerable effort has been invested in monitoring dissolved reactive phosphorus and total phosphorus in the water column, but less is known about the speciation of phosphorus, particularly in the sediment. This compartment is an important and dynamic reservoir of phosphorus and a potential long-term source of phosphorus release to the water column by the sediment–water interface. This paper investigates the solid-phase speciation and reorganisation of phosphorus within the sediments of a shallow lake system in south-east Australia (the Gippsland Lakes) which suffers from recurring harmful algae blooms. Various strategies are proposed to determine the minimum realistic timescale required to deplete the sediment of labile and reactive phosphorus species. Abstract. Solid-phase phosphorus pools in the sediments of two shallow lakes (Wellington and Victoria) in the Gippsland Lakes coastal lagoon system of south-east Australia are discussed. Cores (20-cm depth) were taken in summer and winter in both lakes and a sequential extraction scheme (SEDEX) was used to profile the exchangeable P (Pex), iron oxide/hydroxide bound P (PFe), authigenic P (Pauth), detrital P (Pdet) and organic P (Porg). Pore-water (Ppw) dissolved reactive phosphorus concentration profiles were also measured. The dominant forms of P were PFe (up to 53%) and Porg (35–55%), with the PFe fraction playing a key role in the short-term retention of P in the sediment. Benthic phosphorus fluxes at the sediment–water interface (μmol m–2 d–1) were determined from the sequential extraction data. The results were compared with flux measurements from the complementary approaches of benthic chamber experiments and Fickian diffusion calculations, to allow an insight into the nature and seasonal variations of the fluxes. The burial flux of phosphorus was also estimated from excess 210Pb profiles in the sediment of the lakes. All of these data were used to produce a phosphorus budget for the Gippsland Lakes which suggested that the sediment represents a substantial source of phosphorus within the lakes and thus clearly highlights the importance of the sedimentary compartment in shallow eutrophic ecosystems. Minimum realistic timescales for complete labile phosphorus depletion from the sediment (assuming no resupply from the sediment–water interface) were calculated and ranged from 8 to 22 years.

The West Kingfish Field in the Gippsland Basin, offshore Victoria, has been developed from the West King-fish platform by Esso Australia Ltd (operator) and BHP Petroleum.The structure is an essentially separate, largely stratigraphic accumulation that forms the western flank of the Kingfish feature. A total of 19 development wells were drilled from the West Kingfish platform between October 1982 and May 1984. Information provided by these wells was used in a West Kingfish post-development geologic study and a reservoir simulation study.As a result of these studies the estimated recoverable oil volume has been increased 55 per cent to 27.0 stock tank gigalitres (170 million stock tank barrels). The studies also formed the technical basis for obtaining new oil classification of the P-1.1 reservoir which is the only sand body that has been found in the Gurnard Formation in the Kingfish area.The simulation study was accomplished with an extremely high level of efficiency due to the extensive and effective use of computer graphics technology in model construction, history matching and predictions.Computer graphics technology has also been used very effectively in presenting the simulation study results in an understandable way to audiences with various backgrounds. A portable microcomputer has been used to store hundreds of graphic displays which are projected with a large screen video projector.Presentations using this new display technology have been well received and have been very successful in conveying the results of a complex reservoir simulation study and in identifying future field development opportunities to audiences with various backgrounds.

Within Australia, carbon capture and storage (CCS) and carbon capture, utilisation and storage will play a significant role as part of an ‘all of the above’ approach to managing greenhouse gas emissions. Two CCS projects are currently operating: Gorgon and the Otway CCS project. The Gorgon and Jansz-Io fields contain approximately 14% carbon dioxide (CO2). The CO2 is brought to shore at Barrow Island and injected into the Dupuy Formation saline aquifer at a depth of 2500 m. While the project has experienced delays with start-up and operational issues, to July 2021 nearly 5 MMt of CO2 had been injected. The Otway CCS Project is a research facility used to study subsurface CO2 storage and behaviour within saline aquifers and depleted reservoirs. Since the start of the project in 2007 a total of 95 000 t of CO2 has been stored. Final Investment Decision was taken for the Moomba CCS project on 1 November 2021 and for the Leigh Creek Urea project in March 2021. In addition, feasibility studies are being carried out across multiple projects within Australia including the South West and Mid-West Projects in the Perth Basin, CarbonNet in Victoria’s Latrobe Valley and Gippsland Basin and the Moonie oil field EOR, Integrated Surat Basin Project and the ATP 2062-P Buckland Basalt projects in the Bowen-Surat Basin. A CCS hub at Bayu-Undan is being assessed as a possible option to reduce the carbon footprint of the Barossa, Caldita and Evans Shoals projects, and feasibility studies are underway into large-scale multi-user CCS hubs near both Darwin and Karratha.

Esso Australia Pty Ltd (Esso), in a joint venture with BHP Petroleum Pty Ltd, operates 23 oil and gas production platforms and subsea facilities off the Victorian coast near Gippsland, Australia. The underlying reservoirs have multi-darcy sands and a strong aquifer water drive, so in addition to oil and gas, the extraction activities result in substantial amounts of produced formation water (PFW). Following on-platform treatment, PFW containing a variety of hydrocarbons, ions and inorganics, such as calcium, ammonia, sulfate and trace metals, is discharged into the receiving environment. This paper reports on a study undertaken to investigate the potential effects of PFW discharges from two platforms (Tuna (TNA) and West Kingfish (WKF)) on the receiving environment. Four complementary sampling approaches were used to address the objectives of the study: (1) measure and estimate the dilution of Rhodamine FWT dye solution in the receiving environment following injection into the PFW discharge line, (2) collect and analyse undiluted PFW samples before discharge, (3) collect and analyse marine water samples from within the discharge plume and (4) collect and analyse sediment and benthic infauna samples at various distances away from platforms and at reference locations. Results indicate the rate of PFW dilution within the receiving environment is more rapid than predicted by existing numerical models and that the concentration of all analytes present in PFW were below Australian and New Zealand Environment Conservation Council (ANZECC) 2000 guideline trigger values for 80% protection; moreover, with one exception, analytes were not detected above background levels more than 59 m from the platform. With the exception of a few samples containing metals, specifically arsenic, copper, lead, zinc and nickel, concentrations of analytes in the majority of sediment samples collected were below the ANZECC 2000 and revised 2013 sediment quality guidelines. A diverse range of benthic infauna were sampled, with the abundance of a limited number of taxa influenced by distance from individual platforms. No substantial differences in abundances of benthic infauna were detected at distances greater than 1.3 km from TNA and 1.0 km from WKF, compared with reference locations. These results indicate that PFW discharges from TNA and WKF likely represent a low risk to the receiving environment.

Presented on Tuesday 17 May: Session 8 Within Australia, carbon capture and storage (CCS) and carbon capture, utilisation and storage will play a significant role as part of an ‘all of the above’ approach to managing greenhouse gas emissions. Two CCS projects are currently operating: Gorgon and the Otway CCS project. The Gorgon and Jansz-Io fields contain approximately 14% carbon dioxide (CO2). The CO2 is brought to shore at Barrow Island and injected into the Dupuy Formation saline aquifer at a depth of 2500 m. While the project has experienced delays with start-up and operational issues, to July 2021 nearly 5 MMt of CO2 had been injected. The Otway CCS Project is a research facility used to study subsurface CO2 storage and behaviour within saline aquifers and depleted reservoirs. Since the start of the project in 2007 a total of 95 000 t of CO2 has been stored. Final Investment Decision was taken for the Moomba CCS project on 1 November 2021 and for the Leigh Creek Urea project in March 2021. In addition, feasibility studies are being carried out across multiple projects within Australia including the South West and Mid-West Projects in the Perth Basin, CarbonNet in Victoria’s Latrobe Valley and Gippsland Basin and the Moonie oil field EOR, Integrated Surat Basin Project and the ATP 2062-P Buckland Basalt projects in the Bowen-Surat Basin. A CCS hub at Bayu-Undan is being assessed as a possible option to reduce the carbon footprint of the Barossa, Caldita and Evans Shoals projects, and feasibility studies are underway into large-scale multi-user CCS hubs near both Darwin and Karratha. To access the presentation click the link on the right. To read the full paper click here