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Mitchell, M. M. "ELEVATED MID-CRETACEOUS PALAEOTEMPERATURES IN THE WESTERN OTWAY BASIN: CONSEQUENCES FOR HYDROCARBON GENERATION MODELS." APPEA Journal 37, no. 1 (1997): 505. http://dx.doi.org/10.1071/aj96030.
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The Otway Basin formed during the Mesozoic separation of Antarctica and Australia. A study of apatite fission track (FT) analysis and vitrinite reflectance (VR) data from borehole samples in the western Otway Basin was initiated to elucidate some of the thermal and structural complexities of this region.Interpretation of results suggest that some areas experienced regionally elevated palaeotemperatures, however, much of the region is at present-day maximum temperatures. Where cooling from maximum palaeotemperatures is observed, the timing may be grouped over three main intervals as follows; mid-Cretaceous, Late Cretaceous to Early Tertiary, and Tertiary. Cooling was facilitated by a decline in geothermal gradient, uplift and erosion, or both. Evidence for a decline in geothermal gradient from values >55°C/km in the mid- Cretaceous is recognised in several wells. Elevated mid- Cretaceous palaeogeothermal gradients (50−60°C/km) have been reported for the eastern Otway Basin, suggesting that these high temperatures were a regional phenomena. Cooling by uplift and erosion at this time was minimal throughout the western Otway Basin in contrast to the kilometre scale uplift and erosion reported for the eastern Otway Basin and adjacent basement inland of this section of the rift.The relative early maturation of the Otway Supergroup during mid-Cretaceous regionally elevated geothermal gradients, and subsequent basin restructuring, are key factors affecting hydrocarbon preservation in the western Otway Basin. Strategies for identification of prospective areas include identification of regions that have remained at moderate temperatures during the Early Cretaceous, and have not undergone burial under a thick Upper Cretaceous to Tertiary section.
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Cooper, G. T., and K. C. Hill. "CROSS-SECTION BALANCING AND THERMOCHRONOLOGICAL ANALYSIS OF THE MESOZOIC DEVELOPMENT OF THE EASTERN OTWAY BASIN." APPEA Journal 37, no. 1 (1997): 390. http://dx.doi.org/10.1071/aj96024.
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Recent advances in cross-section balancing software have simplified the application of basic geometric constraints to the analysis of basin development. Geometric analysis of field and seismic data allows the user to verify initial interpretations and also elucidates important information about the structural evolution of a basin. Principally, computerised balancing and restoration of cross-sections assists in constraining:the amount of crustal extension;trap geometries, particularly fault geometries through time;the geometry of key horizons at any time, revealing basin morphology and migration paths;the time and amount of maximum burial and hence hydrocarbon migration; andthe likely mechanisms involved in basin evolution. In turn, these parameters can be used to further assess hydrocarbon prospectivity by providing useful data for lithospheric modelling.This study utilises 2D cross-section balancing software (Geosec™) to decompact, balance and restore a series of regional onshore-offshore cross-sections based on both reflection seismic data in the Torquay Embayment and field mapping in the Otway Ranges. The thickness of eroded strata has been constrained by Apatite Fission Track and Vitrinite Reflectance analyses. The resulting section restoration suggests that the eastern Otway Basin experienced extension of 26 per cent in the Early Cretaceous and that the Otway Ranges were subjected to −8 per cent shortening during mid-Cretaceous inversion and −4 per cent shortening during Mio-Pliocene inversion.The structural style of the Otway Ranges and Torquay Embayment is typified by steep, relatively planar, en echelon, N and NE-dipping Early Cretaceous extension faults that were subsequently inverted and eroded during the Cenomanian and Mio-Pliocene. The structural style of the region shows strong similarities with oblique- rift analogue models suggesting that the extensional history of the region was strongly controlled by prevailing basement fabric.Lower Cretaceous source rocks in the eastern Otway Basin reached maximum maturity prior to mid-Cretaceous inversion with the exception of parts of the Torquay Embayment which may not have experienced significant uplift and erosion at this time. The lack of subsidence in the eastern Otway Basin prevented the deposition of significant amounts of Upper Cretaceous sediments which are proven reservoirs in the western Otway Basin and Gippsland Basin. Subsequent Tertiary burial was insufficient, in most regions, to allow the source rocks re-enter the oil generation window.
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Bernecker, T., and D. H. Moore. "LINKING BASEMENT AND BASIN FILL: IMPLICATIONS FOR HYDROCARBON PROSPECTIVITY IN THE OTWAY BASIN REGION." APPEA Journal 43, no. 1 (2003): 39. http://dx.doi.org/10.1071/aj02002.
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Since the offshore discoveries of economic gas accumulations at Geographe and Thylacine, the Otway Basin has become the focus of an exploration resurgence. Its proximity to major markets ensures the discoveries will be commercially valuable. The latest successes in the basin are mainly due to modern 3D-seismic techniques. While the upper sedimentary succession has been imaged at high resolution, details of the deeper successions, however, remained obscure.An integrated study of magnetic, gravimetric, bathymetric and deep seismic data-sets has outlined the way that pre-existing basement fractures controlled much of the later basin-evolution, the structural style and the distribution of hydrocarbon bearing structures.The Otway Basin formed by the profound interaction between crustal fabric in the Proterozoic and Palaeozoic basement and the extensional stresses during Gondwana break-up. Overall, three different rift systems can be distinguished:Early ENE-trending Jurassic to Early Cretaceous rifts are an extension of the E-W rift system in Western Australia and South Australia, Early WNW Late Jurassic to Early Cretaceous rifts are connected to the ENE set and include the western Otway Basin east of the Robe Trough and the Torquay Sub-basin, and Early Cretaceous NNW transtensional rifts in the southern part of the Shipwreck Trough. These control the La Bella, Thylacine and Geographe discoveries, all of which overlie the Neoproterozoic to Cambrian Selwyn Block.Within these rift systems, the Jurassic to Cretaceous rifts along the continental shelf break coincide with the northern edge of the Voluta Trough, whilst the mid-slope rifts are part of the deep Voluta Trough and were possibly generated during the Late Cretaceous.Although the potential field data do not directly delineate hydrocarbon accumulations, when integrated with other data they provide powerful tools for exploration. For instance, it is possible to map the distribution of Paleocene channels that overlie the basement and represent likely reservoir facies, while data integration with palaeoenvironmental interpretations can highlight areas in which source rock facies developed.Regionally, the way the rifts have formed with respect to the basement fabric suggests that the dominant extension direction in the basin was N to NNW. Integrating the interpretation with regional studies in the western Tasmanian region supports the proposition that the western part of the south Tasman Rise was once the outer part of the upper plate adjacent to the deepwater parts of the Otway Basin SW of Cape Otway.
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McKenzie, G. Merna, and A. Peter Kershaw. "A Vegetation History and Quantitative Estimate of Holocene Climate from Chapple Vale, in the Otway Region of Victoria, Australia." Australian Journal of Botany 45, no. 3 (1997): 565. http://dx.doi.org/10.1071/bt96051.
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A well-dated pollen record from Chapple Vale in the north of the Otway region provides a detailed history of vegetation and environments through the last c. 7000 years. From the commencement of the record, a stand of cool temperate rainforest, dominated by Nothofagus cunninghamii (Hook.) Oerst., grew on or around the site and was surrounded by eucalypt-dominated tall open forest. Between c. 5200 and 4600 years BP (before present), the rainforest declined and tall open forest predominated. Some time after 4400 years BP there was a major and consistent increase in charcoal values, suggesting an increase in burning, the progressive development of scrub–heath vegetation on site and the replacement of tall open forest vegetation by eucalypt woodland surrounding the site. The fossil evidence for N. cunninghamii on the site and its present restriction to wetter areas and gullies of the Otway Ranges indicate, from the application of the present bioclimatic range of the species, a mean annual temperature and winter temperatures that were c. 1˚C cooler than present, and summer temperatures that were possibly slightly cooler than present, together with a much higher effective precipitation from the commencement of the record until c. 4600 years BP. These climatic estimates are in accord with those derived from a similar study of changing distributions of N. cunninghamii in the Central Highlands of lower mean annual and cooler summer temperatures and higher effective precipitation over this time span. However, for winter, the evidence is equivocal. While the Otway estimates suggest lower temperatures, the Central Highlands findings show slightly higher temperatures. Taking into account additional present-day records for N. cunninghamii, it is likely that the Otway estimates are the most reliable.
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Mehin, K., and A. G. Link. "KITCHENS, KETTLES AND CUPS OF HYDROCARBONS, VICTORIAN OTWAY BASIN." APPEA Journal 37, no. 1 (1997): 285. http://dx.doi.org/10.1071/aj96018.
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Evaluation of Early Cretaceous source rocks within the onshore Victoria Otway Basin has revealed that thick, mature shales containing predominantly gas-prone and in local concentrations, oil-prone macerals exist northwest of Portland, in the Tyrendarra Embayment, and around the Port Campbell region.Current results of Rock-Eval, bulk composition, gas chromatography, and biomarker analyses, coupled with geohistory and hydrocarbon generation interpretations, indicate that at least three phases of oil generation and expulsion occurred within the basin. The earliest phase, which coincided with the maximum heatflow in the crust around 100 Ma, resulted in the charging of the existing stratigraphic/shoestring traps of the basin. The second and third phases occurred in the eastern end of the basin at around 85 and 60 Ma. There is also evidence to suggest that structural traps of the eastern areas were formed later, during Oligocene time, and that these traps are probably still receiving late-stage charges of hydrocarbons.Although the sparse well density in the basin has resulted in limited, non-uniforin sampling opportunities, several regions with good Early Cretaceous source rocks can be recognised. Some of these good source rock areas are in close proximity to the several known hydrocarbon shows and producing fields. These current studies, which also include a source rock risk analysis indicating source rock adequacy, show that locations for future exploration could include the Casterton-Portland-Mt Gambier western region, the Peterborough-Port Campbell eastern region, and the prospective close peripheries and offshore extensions of these regions.
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Bendall, Betina, Anne Forbes, Dan Revie, Rami Eid, Shannon Herley, and Tony Hill. "New insights into the stratigraphy of the Otway Basin." APPEA Journal 60, no. 2 (2020): 691. http://dx.doi.org/10.1071/aj19035.
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The Otway Basin is one of the best known and most actively explored of a series of Mesozoic basins formed along the southern coastline of Australia by the rifting of the Antarctic and Australian plates during the Cretaceous. The basin offers a diversity of play types, with at least three major sedimentary sequences forming conventional targets for petroleum exploration in the onshore basin. The Penola Trough in South Australia has enjoyed over 20 years of commercial hydrocarbon production from the sandstones of the Early Cretaceous Otway Group comprising the Crayfish Subgroup (Pretty Hill Formation and Katnook sandstones) and Eumeralla Formation (Windermere Sandstone Member). Lithostratigraphic characterisation and nomenclature for these sequences are poorly constrained, challenging correlation across the border into the potentially petroleum prospective Victorian Penola Trough region. The Geological Survey of Victoria (GSV), as part of the Victorian Gas Program, commissioned Chemostrat Australia to undertake an 11-well chemostratigraphic study of the Victorian Otway Basin. The South Australia Department for Energy and Mining, GSV and Chemostrat Australia are working collaboratively to develop a consistent, basin-wide schema for the stratigraphic nomenclature of the Otway Basin within a chemostratigraphic framework. Variability in the mineralogy and hence inorganic geochemistry of sediments reflects changes in provenance, lithic composition, facies changes, weathering and diagenesis. This geochemical variation enables the differentiation of apparently uniform sedimentary successions into unique sequences and packages, aiding in the resolution of complex structural relationships and facies changes. In this paper, we present the preliminary results of detailed geochemical analyses and interpretation of 15 wells from across the Otway Basin and the potential impacts on hydrocarbon prospectivity.
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Nelson, E., R. Hillis, M. Sandiford, S. Reynolds, and S. Mildren. "PRESENT-DAY STATE-OF-STRESS OF SOUTHEAST AUSTRALIA." APPEA Journal 46, no. 1 (2006): 283. http://dx.doi.org/10.1071/aj05016.
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There have been several studies, both published and unpublished, of the present-day state-of-stress of southeast Australia that address a variety of geomechanical issues related to the petroleum industry. This paper combines present-day stress data from those studies with new data to provide an overview of the present-day state-of-stress from the Otway Basin to the Gippsland Basin. This overview provides valuable baseline data for further geomechanical studies in southeast Australia and helps explain the regional controls on the state-of-stress in the area.Analysis of existing and new data from petroleum wells reveals broadly northwest–southeast oriented, maximum horizontal stress with an anticlockwise rotation of about 15° from the Otway Basin to the Gippsland Basin. A general increase in minimum horizontal stress magnitude from the Otway Basin towards the Gippsland Basin is also observed. The present-day state-of-stress has been interpreted as strike-slip in the South Australian (SA) Otway Basin, strike-slip trending towards reverse in the Victorian Otway Basin and borderline strike-slip/reverse in the Gippsland Basin. The present-day stress states and the orientation of the maximum horizontal stress are consistent with previously published earthquake focal mechanism solutions and the neotectonic record for the region. The consistency between measured present-day stress in the basement (from focal mechanism solutions) and the sedimentary basin cover (from petroleum well data) suggests a dominantly tectonic far-field control on the present-day stress distribution of southeast Australia. The rotation of the maximum horizontal stress and the increase in magnitude of the minimum horizontal stress from west to east across southeast Australia may be due to the relative proximity of the New Zealand segment of the plate boundary.
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McKenzie, G. Merna, and A. Peter Kershaw. "The last glacial cycle from Wyelangta, the Otway region of Victoria, Australia." Palaeogeography, Palaeoclimatology, Palaeoecology 155, no. 1-2 (January 2000): 177–93. http://dx.doi.org/10.1016/s0031-0182(99)00100-5.
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Hill, K. A., D. M. Finlayson, K. C. Hill, and G. T. Cooper. "MESOZOIC TECTONICS OF THE OTWAY BASIN REGION: THE LEGACY OF GONDWANA AND THE ACTVE PACIFIC MARGIN—A REVIEW AND ONGOING RESEARCH." APPEA Journal 35, no. 1 (1995): 467. http://dx.doi.org/10.1071/aj94030.
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Mesozoic extension along Australia's southern margin and the evolution and architecture of the Otway Basin were probably controlled by three factors: 1) changes in global plate movements driven by mantle processes; 2) the structural grain of Palaeozoic basement; and, 3) changes in subduction along Gondwana's Pacific margin. Major plate realignments controlled the Jurassic onset of rifting, the mid-Cretaceous break-up and the Eocene onset of rapid spreading in the Southern Ocean.The initial southern margin rift site was influenced by the northern limit of Pacific margin (extensional) Jurassic dolerites and the rifting may have terminated dolerite emplacement. Changed conditions of Pacific margin subduction (e.g. ridge subduction) in the Aptian may have placed the Australia-Antarctic plates into minor compression, abating Neocomian southern margin rifting. It also produced vast amounts of volcanolithic sediment from the Pacific margin arc that was funnelled down the rift graben, causing additional regional subsidence due to loading. Albian orogenic collapse of the Pacific margin, related to collision with the Phoenix Plate, influenced mid-Cretaceous breakup propagating south of Tasmania and into the Tasman Sea.Major offsets of the spreading axis during breakup, at the Tasman and Spencer Fracture zones, were most likely controlled by the location of Palaeozoic terrane boundaries. The Tasman Fracture System was reactivated during break-up, with considerable uplift and denudation of the Bass failed rift to the east, which controlled Otway Basin facies distribution. Palaeozoic structures also had a significant effect in determining the half graben orientations within a general N-S extensional regime during early Cretaceous rifting. The late Cretaceous second stage of rifting, seaward of the Tartwaup, Timboon and Sorell fault zones, left a stable failed rift margin to the north, but the attenuated lithosphere of the Otway-Sorell microplate to the south records repeated extension that led to continental separation and may be part of an Antarctic upper plate.
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Williamson, P. E., G. W. O'Brien, M. G. Swift, E. A. Felton, A. S. Scherl, J. Lock, N. F. Exon, and D. A. Falvey. "HYDROCARBON POTENTIAL OF THE OFFSHORE OTWAY BASIN." APPEA Journal 27, no. 1 (1987): 173. http://dx.doi.org/10.1071/aj86016.
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The Otway Basin is one of three sedimentary basins in the Bass Strait region and is situated west of the Bass and Gippsland Basins. It trends NW-SE, straddling the southern Australian coastline for 500 km between the Mornington Peninsula in Victoria and Cape Jaffa in South Australia. It has an average width of 200 km and an average offshore width, in water depths of less than 200 m, of 50 km.The offshore basin consists of three main tectonic units: the Mussel Platform in the east, the Voluta Trough, which occurs in the centre of the basin, and the Crayfish Platform in the west. Structures are formed predominantly by Cretaceous normal faults, downthrown to the continent-ocean boundary, and displacing landward-dipping Cretaceous strata. The sedimentary sequence can reach 10 km in thickness and consists of terrestrial Early Cretaceous sediments of the Otway Group, Late Cretaceous transgressive-regressive terrigenous sediments of the Sherbrook Group, Paleocene-Eocene transgressive-regressive, terrigenous and carbonate sediments of the Wangerrip and Nirranda Groups, and Oligocene-Miocene shelf carbonates of the Heytesbury Group.Since the early 1960s, about 50 exploration wells have been drilled onshore and 17 offshore. Shows of oil, gas and condensate have been widespread in both onshore and offshore wells, though only two small economic fields have so far been discovered; both are onshore. Exploration, particularly during the 1960s and 1970s, was hampered by poor seismic data quality, due primarily to the presence of shallow carbonates.
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Burgin, Hugo B., Khalid Amrouch, Philippe Robion, and David Kulikowski. "An integrated approach to determining 4D stress development at Castle Cove." APPEA Journal 59, no. 1 (2019): 410. http://dx.doi.org/10.1071/aj18173.
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Models for basin evolution and natural fracture development often contain many uncertainties. Multiscale approaches to structural analysis assist in reducing these by providing checkpoints for structural evolution to better constrain the development of paleostress phases through time. In this study, we integrate the analysis of calcite twins, magnetic fabrics, stylolites and natural fractures at Castle Cove in the eastern Otway Basin, producing a five-phase model for stress evolution consisting of: phase 1 ~NW–SE Mid-Cretaceous strike-slip or compression; phases 2 and 3 Late Cretaceous extension, coinciding with the development of ~NW–SE and ~NE–SW striking extensional fracture sets; phase 4 ~NE–SW strike-slip and compression, representing an enigmatic period of stress evolution with respect to the current understanding of the Otway Basin; and phase 5, present day ~NW–SE strike-slip stress. The results contribute to a 4D structural history construction for the eastern Otway Basin and suggest that the evolution of the region may require reassessing in order to determine the timing and nature of the detected ~NE–SW oriented compressional event. This study also demonstrates how the use of a calcite stress inversion technique can assist in providing mechanical checkpoints for the evolution of complex natural fracture networks, which can easily be expanded within the sub-surface.
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De Fina, Aaron, Marc Chable, and Cameron Wills. "360-degree stakeholder management driving successful CO2 storage research." APPEA Journal 59, no. 2 (2019): 565. http://dx.doi.org/10.1071/aj18215.
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The CO2CRC Otway Project continues to demonstrate that carbon capture and storage is a viable option for CO2 mitigation. The CO2CRC Otway Project is Australia’s first CO2 demonstration project, with two projects completed, involving geological storage of some 80000 tonnes of CO2 over the past 10 years. The project was initially authorised for a single stage with a finite life, but the growing requirements of the global carbon capture and storage community required further research on carbon capture and storage technologies and behaviour (via Stages 2 and 3), and so the project was extended. CO2CRC has undertaken 360-degree stakeholder engagement processes throughout the project, regularly consulting with regulators, governments, industry, partners, researchers and the community. This has been especially important as the project changed, operating in a niche space between Victorian environment, petroleum and water Acts. This process has allowed CO2CRC to contribute to alignment efforts within regulatory bodies, to enhance regulations to cover project activities, ensuring best practices are documented and observed to the satisfaction of the regulators and wider community. The Otway Basin in south-west Victoria is a region not immune to broader community concerns regarding the oil and gas and other industries. The surrounding area is predominately dairy farming, with locals relying heavily on the aquifers beneath their land. Although such a backdrop suggests potentially high levels of concern and scrutiny, especially when projects necessitate drilling or other invasive activities, the project has maintained strong local stakeholder engagement and support due to ongoing implementation and evaluation of the stakeholder management processes.
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Jones, R. M., P. Boult, R. R. Hillis, S. D. Mildren, and J. Kaldi. "INTEGRATED HYDROCARBON SEAL EVALUATION IN THE PENOLATROUGH, OTWAY BASIN." APPEA Journal 40, no. 1 (2000): 194. http://dx.doi.org/10.1071/aj99011.
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Seals are one of the main components of the petroleum system, yet their evaluation has received surprisingly little attention in terms of integrated risk assessment. This paper emphasises the need for an integrated multi-disciplinary approach for robust cap and fault seal evaluation so to minimise seal risk. The region of study is the Penola Trough, Otway Basin, where recent improvements in seismic quality, stratigraphic modelling and additional well control have greatly enhanced regional prospectivity.The Laira Formation has the lowest cap seal risk of Penola Trough strata based on empirical data. The Eumeralla Formation has a similar gamma ray log signature to the Laira Formation yet contains a higher frequency of sandy, relatively high permeability horizons. These horizons increase the likelihood of fault juxtaposition and the development of leaky windows that allow cross fault communication.Faults in the Penola Trough display fractal characteristics from seismic to core scale. A prediction of regional fault extension and deformation intensity below seismic resolution is viable since fault systems appear to be systematic. Extrapolation of fault populations to the millimetre scale shows good agreement with fault density recorded in core from a fault damage zone. Deformation intensities close to seismically resolvable faults are indicative of inner damage zone geometry where faults form linked cluster arrays. Microstructural fault analysis indicates the dominant fault processes in the Upper Crayfish Group are grain boundary sliding and cataclasis with gouge quartz cementation. Petrophysical analysis indicates these faults are able to support gas columns of up to 102 m.The relative probability of seal failure due to the development of effective structural permeability within the in-situ stress field indicates that planes at the greatest risk of failure are steeply dipping (>60°) and strike between 110°N and 200°N. Open fractures crosscutting pre-existing faults have been identified through microstructural examination and these may provide a mechanism for trap leakage and tertiary hydrocarbon migration. An integrated technique for mapping the relative risk of seal breach due to the development of effective structural permeability at the seismic scale is also presented.
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Noll, C. A., and M. Hall. "FLUVIAL ARCHITECTURE AND THE TECTONIC CONTROL ON DEPOSITION OF ONSHORE EUMERALLA FORMATION, OTWAY RANGES, VICTORIA: IMPLICATIONS FOR EXPLORATION IN THE EARLY CRETACEOUS OTWAY BASIN." APPEA Journal 43, no. 1 (2003): 99. http://dx.doi.org/10.1071/aj02005.
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Spectacular outcrops of the terrestrial Aptian-Albian Eumeralla Formation are exposed in the Skenes Creek– Wongarra region, located on the eastern margin of the Otway Ranges, Victoria. The succession comprises mudstone-dominated floodplain and lacustrine successions and fluvially-derived sandstones. Lithofacies observed in the study area comprise intraformational and exotically derived conglomerate, massive and planar laminated sandstone, trough and tabular cross-bedded sandstone, ripple laminated sandstone, interbedded sandstone and mudstone, massive to laminated mudstone and thin coal seams. Architectural analysis of the fluvial system reveals these lithofacies are arranged into architectural elements that include channel elements, sandy bedforms, downstream and lateral accretion elements, laminated sand sheets and overbank fines elements.The fluvial system is characterised by low-sinuousity, braided river channels with high width to depth ratios. Palaeocurrent data indicates that the generally westward palaeoflow is interpreted to have been diverted into local axial-through drainage patterns by active northeast trending normal faults. One of these, the Skenes Creek Fault, is also likely to have structurally isolated floodplain and lacustrine successions from the main channel belt, leading to the deposition of an anomalously thick coal measure sequence in the hanging wall of the fault. The local study therefore provides insight into regional lithofacies and potential source rock distributions, and the associated tectonostratigraphic evolution of the Eumeralla Formation in the eastern Otway Basin. While the nature of the Eumeralla Formation sandstone does not lend itself to good reservoir properties, the geometry and internal structure of the sands provide an excellent model for other fluvial sandstone reservoir reconstructions.
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McKenzie, G. Merna, and A. Peter Kershaw. "A Holocene pollen record from cool temperate rainforest, Aire crossing, the Otway region of Victoria, Australia." Review of Palaeobotany and Palynology 132, no. 3-4 (December 2004): 281–90. http://dx.doi.org/10.1016/j.revpalbo.2004.07.006.
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Lovell, Harold, Chris R. Stokes, and Michael J. Bentley. "A glacial geomorphological map of the Seno Skyring-Seno Otway-Strait of Magellan region, southernmost Patagonia." Journal of Maps 7, no. 1 (January 2011): 318–39. http://dx.doi.org/10.4113/jom.2011.1156.
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Cook, Peter, Yildiray Cinar, Guy Allinson, Charles Jenkins, Sandeep Sharma, Michael Soroka, and Jo Ann Tan. "Enhanced gas recovery, CO2 storage and implications from the CO2CRC Otway Project." APPEA Journal 51, no. 2 (2011): 684. http://dx.doi.org/10.1071/aj10064.
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Successful completion of the first stage of the CO2CRC Otway Project demonstrated safe and effective CO2 storage in the Naylor depleted gas field and confirmed our ability to model and monitor subsurface behaviour of CO2. It also provided information of potential relevance to CO2 enhanced gas recovery (EGR) and to opportunities for CO2 storage in depleted gas fields. Given the high CO2 concentration of many gas fields in the region, it is important to consider opportunities for integrating gas production, CO2 storage in depleted gas fields, and CO2-EGR optimisation within a production schedule. The use of CO2-EGR may provide benefits through the recovery of additional gas resources and a financial offset to the cost of geological storage of CO2 from gas processing or other anthropogenic sources, given a future price on carbon. Globally, proven conventional gas reserves are 185 trillion m3 (BP Statistical Review, 2009). Using these figures and Otway results, a replacement efficiency of 60 % (% of pore space available for CO2 storage following gas production) indicates a global potential storage capacity—in already depleted plus reserves—of approximately 750 Gigatonnes of CO2. While much of this may not be accessible for technical or economic reasons, it is equivalent to more than 60 years of total global stationary emissions. This suggests that not only gas—as a lower carbon fuel—but also depleted gas fields, have a major role to play in decreasing CO2 emissions worldwide.
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Williams, M. L., A. J. Boulton, M. Hyde, A. J. Kinnear, and C. D. Cockshell. "ENVIRONMENTAL IMPACT OF SEISMIC OPERATIONS IN THE OTWAY BASIN, SOUTH AUSTRALIA." APPEA Journal 34, no. 1 (1994): 741. http://dx.doi.org/10.1071/aj93054.
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The Department of Mines and Energy, South Australia (DME) contracted Michael Williams and Associates Pty Ltd to audit the environmental management of seismic exploration operations in the South Australian Otway Basin. The audit was carried out in early 1992 and covered petroleum exploration operators and DME environmental management systems. An innovative field sampling technique was developed to compare the environmental impact of two different seismic line clearing techniques. Recovery of native vegetation as measured by vegetation structure was also quantified.The audit found DME to have a dynamic and integrated environmental management system while company systems varied in standard. Wide consultation assisted the audit process.As a result of clearing for agriculture, native vegetation covers only six per cent of the Otway Basin. With the strict limitations to broad-scale vegetation clearance since the mid-1980s and the cessation since 1991, the greatest environmental impact of seismic exploration is the clearance of native vegetation for access by seismic vehicles. Native vegetation structure and associated abiotic variables on seismic lines and adjacent control sites, were subject to a classification and ordination analysis which compared the impact of seismic lines constructed by bulldozer or Hydro-ax (industrial slasher). Post-seismic recovery rates of three different vegetation associations were also determined. This analytical technique permits the effects of seismic line clearance to be compared with the natural variability of specific vegetation associations within a region. In interpreting the results however, there is a confounding effect of line type and year as most of the more recent seismic lines were constructed using a Hydro-ax. Results indicate that Hydro-ax clearing affects vegetation structure less than bulldozing. Most Hydro-ax sites recovered within a few years whereas some sites, bulldozed as early as 1971, particularly tussock grasslands, have not yet recovered.This study provides a significant break-through in the debate about the persistence of seismic impacts on native vegetation. As a rapid preliminary assessment, sampling vegetation structure rather than floristics, provides a cost-effective audit and monitoring technique which can be used by non-specialists in a range of petroleum exploration environments. Any significant structural differences may require more detailed analysis to determine if floristic composition also differed.
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Potts, BM, and GJ Jordan. "The Spatial Pattern and Scale of Variation in Eucalyptus globulus ssp Globulus: Variation in Seedling Abnormalities and Early Growth." Australian Journal of Botany 42, no. 4 (1994): 471. http://dx.doi.org/10.1071/bt9940471.
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Variation in seedling abnormalities and 2- and 4-year growth were studied in a trial in north-westem Tasmania established from 594 open-pollinated families from throughout the geographical range of Eucalyptus globulus Labill. ssp, globulus and populations intergrading with other subspecies. Most (77-80%) of the total (phenotypic) variation in growth traits occurred within families. The genetic variation between families within localities (within c. 10 krn; 13-15% of the total variation), between localities within regions (within c. 100-150 km; c: 4%) and between regions (3-8%) was generally highly significant. However, regional and locality components together accounted for only a small proportion of the total phenotypic variation. Little differentiation was detected between separate sampling sites within localities. Estimates of individual narrow-sense heritabilities were markedly higher than previous reports and were 0.38 for conic volume and 0.41 for height at 4 years, assuming a coefficient of relatedness of 0.4 amongst open-pollinated sibs. On average, progenies from the Otway Ranges region were the fastest growing at the test site, followed by those from King Island. Parent trees with high breeding values were concentrated in the Otway Ranges, Strzelecki Ranges and far southeastem Tasmania with the Bass Strait island localities having intermediate frequencies. Forest fragmentation through clearing for agriculture appears to have had a deleterious effect on the quantitative genetic structure of intergrade populations consistent with high levels of inbreeding. Remnant populations tended to have higher levels of severely abnormal seedlings, higher mortality and poorer growth, and higher heritability estimates and variability both within and between families. Advanced generation hybridisation and inbreeding due to long periods of isolation in small, relict populations may also have had similar effects. Populations sampled are, therefore, likely to have markedly different levels of inbreeding which may have inflated differences between localities and may have important consequences for the exploitation of this material for breeding.
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NIEDBAŁA, WOJCIECH, and ANETTA SZYWILEWSKA-SZCZYKUTOWICZ. "Ptyctimous mites (Acari, Oribatida) of Victoria (Australia)." Zootaxa 4344, no. 1 (November 6, 2017): 47. http://dx.doi.org/10.11646/zootaxa.4344.1.2.
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A list of 37 species of ptyctimous mites from the State of Victoria, Australia, is provided. Seven species new for science are described and further seven are recorded for the first time in Victoria. The genus Arphthicarus has been discovered in Victoria and is represented by two new species. Zoogeographical distribution of each species is provided. Analysis of the ptyctimous fauna from four Victorian areas (Otway Ranges, Yarra Ranges, Errinundra Plateau and Strzelecki Ranges) has revealed that four species occur in a large number of specimens in one of the areas. Similarity analyses indicate that the faunas of Errinundra Plateau and Yarra Ranges are the most similar. An overview of state of knowledge on the ptyctimous mites from State of Victoria, Australia and Australasian Region is presented.
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Frieling, Joost, Emiel P. Huurdeman, Charlotte C. M. Rem, Timme H. Donders, Jörg Pross, Steven M. Bohaty, Guy R. Holdgate, Stephen J. Gallagher, Brian McGowran, and Peter K. Bijl. "Identification of the Paleocene–Eocene boundary in coastal strata in the Otway Basin, Victoria, Australia." Journal of Micropalaeontology 37, no. 1 (February 13, 2018): 317–39. http://dx.doi.org/10.5194/jm-37-317-2018.
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Abstract. Detailed, stratigraphically well-constrained environmental reconstructions are available for Paleocene and Eocene strata at a range of sites in the southwest Pacific Ocean (New Zealand and East Tasman Plateau; ETP) and Integrated Ocean Discovery Program (IODP) Site U1356 in the south of the Australo-Antarctic Gulf (AAG). These reconstructions have revealed a large discrepancy between temperature proxy data and climate models in this region, suggesting a crucial error in model, proxy data or both. To resolve the origin of this discrepancy, detailed reconstructions are needed from both sides of the Tasmanian Gateway. Paleocene–Eocene sedimentary archives from the west of the Tasmanian Gateway have unfortunately remained scarce (only IODP Site U1356), and no well-dated successions are available for the northern sector of the AAG. Here we present new stratigraphic data for upper Paleocene and lower Eocene strata from the Otway Basin, southeast Australia, on the (north)west side of the Tasmanian Gateway. We analyzed sediments recovered from exploration drilling (Latrobe-1 drill core) and outcrop sampling (Point Margaret) and performed high-resolution carbon isotope geochemistry of bulk organic matter and dinoflagellate cyst (dinocyst) and pollen biostratigraphy on sediments from the regional lithostratigraphic units, including the Pebble Point Formation, Pember Mudstone and Dilwyn Formation. Pollen and dinocyst assemblages are assigned to previously established Australian pollen and dinocyst zonations and tied to available zonations for the SW Pacific. Based on our dinocyst stratigraphy and previously published planktic foraminifer biostratigraphy, the Pebble Point Formation at Point Margaret is dated to the latest Paleocene. The globally synchronous negative carbon isotope excursion that marks the Paleocene–Eocene boundary is identified within the top part of the Pember Mudstone in the Latrobe-1 borehole and at Point Margaret. However, the high abundances of the dinocyst Apectodinium prior to this negative carbon isotope excursion prohibit a direct correlation of this regional bio-event with the quasi-global Apectodinium acme at the Paleocene–Eocene Thermal Maximum (PETM; 56 Ma). Therefore, the first occurrence of the pollen species Spinizonocolpites prominatus and the dinocyst species Florentinia reichartii are here designated as regional markers for the PETM. In the Latrobe-1 drill core, dinocyst biostratigraphy further indicates that the early Eocene (∼ 56–51 Ma) sediments are truncated by a ∼ 10 Myr long hiatus overlain by middle Eocene (∼ 40 Ma) strata. These sedimentary archives from southeast Australia may prove key in resolving the model–data discrepancy in this region, and the new stratigraphic data presented here allow for detailed comparisons between paleoclimate records on both sides of the Tasmanian Gateway.
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Falvey, D. A., P. A. Symonds, J. B. Colwell, J. B. Willcox, J. F. Marshall, P. E. Williamson, and H. M. J. Stagg. "AUSTRALIA'S DEEPWATER FRONTIER PETROLEUM BASINS AND PLAY TYPES." APPEA Journal 30, no. 1 (1990): 239. http://dx.doi.org/10.1071/aj89015.
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Vast areas of Australia's continental margin sedimentary basins lying seawards of the 200 m water depth line, or shelf edge, are under-explored for petroleum. Indeed, most are essentially unexplored. However, recent advances in drilling and production technology, as well as recent reconnaissance seismic, geochemical, geothermal and seabed sampling data collected by the Bureau of Mineral Resources' (BMR) Marine Division, may reduce the perceived economic risk of many of these deepwater basins relative to their shelf counterparts. Triassic reefs have been identified off the northern Exmouth Plateau and possibly in the deepwater Canning Basin, locally within a predicted oil window. In the deepwater North Perth Basin, major wrench structures have been identified. The deepwater areas of the Great Australian Bight and Otway Basin are actually the main depocentres of a major basin complex lying along the almost totally unexplored southern Australian continental margin. The Latrobe Group in the outer Gippsland Basin is likely to have similar geology to the well explored and productive shelf basin, but remains untested. The Queensland and Townsville troughs, in deepwater off northeast Australia, contain many significant structures typical of unbreached rift systems.All these areas have been risked relative to each other and their prospectivity assessed. The most attractive frontier areas in terms of relative risk may be the Otway and North Perth basins. The highest potential may occur in the deepwater rift troughs off northeast Australia, although the relative risk is very high. Triassic reefs of the Northwest Shelf may have the best prospectivity in the shorter term, given that they are known from drilling in a region with proven source potential and a substantial exploration infrastructure.
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Moriarty, N. J., R. J. Taylor, and G. J. Daneel. "THE SAWPIT STRUCTURE—EVALUATION OF A FRACTURED BASEMENT RESERVOIR PLAY IN THE OTWAY BASIN." APPEA Journal 35, no. 1 (1995): 558. http://dx.doi.org/10.1071/aj94035.
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The 1992 exploration well Sawpit-1, drilled in the Penola Trough of the western Otway Basin, recovered a minor amount of oil (1.5 BBL) from fractured basement. This oil recovery, the first in the basin from rocks older than the Eumeralla Formation, has opened up a new oil play. Fractured basement reservoirs, which can be prolific producers, require prediction of fracture orientation and intensity to be appraised and developed successfully. Such information was sought from a detailed structural analysis of fault attributes (including dip, vertical displacement and heave) using 3D seismic data acquired over the structure in 1993.This 3D seismic data set, acquired at twice the group interval and less than one-quarter the fold of 2D data in the area, has provided the best imaging to date of the complex rifting events of the Sawpit region. Structural analysis of fault attributes indicates an initial south-southwest direction of extension in the Late Jurassic/Early Cretaceous for the Penola Trough, rather than oblique extension as suggested by some authors. This south-southwest extension orientation favours the formation of moderate to high angle fractures trending west-northwest to northwest. Present day minimum horizontal stress is favourably oriented approximately northeast-southwest for these fractures to be open. Interpretation of the 3D seismic data indicates Sawpit-1 probably intersected northeast trending fractures that are oriented perpendicular to the maximum horizontal compressive stress direction and therefore likely to be closed.A deviated well drilled from the northeast would be optimally oriented to intersect northwest trending basement fractures and test a play that has significant oil potential.
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Bunch, Mark, Ric Daniel, Mark Lawrence, Greg Browne, Saju Menacherry, Tess Dance, and Malcolm Arnot. "Multi-scale characterisation of the Paaratte Formation, Otway Basin, for CO2 injection and storage." APPEA Journal 52, no. 2 (2012): 664. http://dx.doi.org/10.1071/aj11078.
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A resurgent interest in the gas potential of the Gulf of Papua has been enhanced by the recent announcement of developing new LNG facilities in Port Moresby. Petroleum Geo-Services (PGS) has recently acquired a 6,000-km2Multi-Client 3D (MC3D) survey in the gulf. Although most of the discoveries in PNG are from the highland areas, the gulf is a proven hydrocarbon province with gas/condensate accumulations previously discovered in several reef build-ups. It is thought that sediments from the Papuan Fold Belt produced clastic dominated deltas in the Gulf area. Although this play is untested offshore, there is evidence these sandy facies exist and could contain hydrocarbons. On the first phase of acquisition/interpretation, an efficient screening workflow called Prospect Scanner, developed to highlight areas of AVO effects in large 3D seismic datasets, was tested. It uses pre-stack seismic time migrated (PSTM) gathers to extract AVO attributes that are then inverted to derive relative acoustic and shear impedance volumes. Using idealised cross-plots, the relationship between Vp/Vs ratio and the Ip values gives a good indication of the fluid and lithology of the tested interval. The results are loaded into a conventional interpretation package for interpretation/visualisation. Prospect Scanner has highlighted previously undrilled turbidite and basin floor fan prospects in the region. The Vp/Vs versus Ip cross-plot shows clustering ofthe sand anomaly and good separation from the majority of the plot. These points correspond to the idealised location for a gas sand. Past concerns about lateral prediction of reservoir presence and quality associated with the basin floor fans can be addressed through this workflow.
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Kilian, R., O. Baeza, S. Breuer, F. Ríos, H. Arz, F. Lamy, J. Wirtz, et al. "Late Glacial and Holocene Paleogeographical and Paleoecological Evolution of the Seno Skyring and Otway Fjord Systems in the Magellan Region." Anales del Instituto de la Patagonia 41, no. 2 (2013): 5–26. http://dx.doi.org/10.4067/s0718-686x2013000200001.
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Finlayson, D. M., C. D. N. Collins, I. Lukaszyk, and E. C. Chudyk. "A transect across Australia's southern margin in the Otway Basin region: crustal architecture and the nature of rifting from wide-angle seismic profiling." Tectonophysics 288, no. 1-4 (March 1998): 177–89. http://dx.doi.org/10.1016/s0040-1951(97)00291-6.
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Lovell, Harold. "Evidence for ice streaming and abrupt high-magnitude proglacial lake drainage in the Seno Skyring-Seno Otway-Strait of Magellan region, southernmost Patagonia." Quaternary International 279-280 (November 2012): 291. http://dx.doi.org/10.1016/j.quaint.2012.08.777.
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Ross, M. I. "INFLUENCE OF PLATE TECTONIC RE-ORGANISATIONS AND TECTONIC SUBSIDENCE ON THE MESOZOIC STRATIGRAPHY OF NORTHWESTERN AND SOUTHEASTERN AUSTRALIA: IMPLICATIONS FOR SEQUENCE STRATIGRAPHIC ANALYSIS." APPEA Journal 35, no. 1 (1995): 253. http://dx.doi.org/10.1071/aj94016.
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Determining and predicting the interplay of plate tectonic events, subsidence, flexure and depositional systems is important in frontier exploration, play concept development, and maturation modelling. A circum-Australian plate tectonic model is here tied to an internally consistent global plate tectonic model to determine the timing and orientation of changes in the lithospheric stress regime induced by plate tectonic changes. One-and three-dimensional geohistory results for the Otway Basin and North West Shelf/Exmouth Plateau are presented, based on an integrated sequence stratigraphic framework. These geohistory results compare the timing and types of changes in subsidence rate to the changes in lithospheric stress due to plate tectonic changes. Changes in tectonic subsidence rate appear to be discrete events related to plate tectonic changes; subsidence events bound major transgressive-regressive facies cycle packages ('supersequences') in a basin. The recognition of sequence system tracts and especially system tract boundaries within a 'supersequence' is enhanced or diminished by processes occurring only during certain phases of the supersequences. Recognition of lowstand systems tracts and sequence boundaries is improved due to erosion during the regressive phase of the supersequence. Conversely, during the transgressive phase of the supersequence, transgressive and highstand system tracts are emphasised and recognition of flooding surfaces improved. Good reservoir sands form during enhanced lowstands, while good source and sealing shales form during enhanced transgressions.In the southeastern Australian Otway Basin, every perturbation of the tectonic subsidence rate during the Late Cretaceous can be correlated directly to a local and/or global plate tectonic event, and each supersequence is bounded by tectonic events. In the North West Shelf/Exmouth Plateau region of Western Australia, the situation is complicated during the Berriasian by uncompensated f lexural load effects related to the rapid formation and filling of multiple Barrow Delta depocentres. Two supersequences correlate to tectonic events, while one supersequence is bounded by a f lexural subsidence event unrelated to regional or global plate tectonic events. Hence not all perturbations of the tectonic subsidence curve are related to tectonic events, and not all supersequences are bound by tectonic events. Without three-dimensional geohistory techniques, it is impossible to isolate the flexural load effects from the effects of plate tectonic events.
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TORRES, JIMENA, and JIMENA RUZ. "Pescadores de la tradición cultural Englefield: Datos preliminares en la zona del Estrecho de Magallanes y mar de Otway XII Region de Magallanes, Chile." Magallania (Punta Arenas) 39, no. 2 (2011): 165–76. http://dx.doi.org/10.4067/s0718-22442011000200012.
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Foster, J. D., and A. J. Hodgson. "PORT CAMPBELL REVIEWED: METHANE AND CHAMPAGNE." APPEA Journal 35, no. 1 (1995): 418. http://dx.doi.org/10.1071/aj94027.
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Gas fields in the Port Campbell Embayment currently supply all the natural gas markets (non-LPG) in western Victoria as well as commercial quantities of carbon dioxide (C02) to industrial markets. Initial discoveries made between 1979 and 1981 were brought on-stream in 1986 with production from the North Paaratte field. Another substantial discovery was made in 1988, the Iona gas field, followed by the Boggy Creek C02 field in 1991, then the My lor and Langley fields in 1994. Discovery of Mylor marked the first recovery of oil from the Late Cretaceous Waarre Formation. Extensive 2D seismic data sets have been recorded in the region since 1979, and the first 3D seismic survey in the Otway Basin was carried out in 1993 extending beyond the area of the initial discoveries. No data on the fields have been published for nearly a decade and little detail about the structural and stratigraphic geology of the Late Cretaceous in the area has been documented. Summaries of the fields are presented incorporating many insights gained from interpretation of the 3D seismic data and its verification by the 'rotary lie detector'.
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Wilson, B. A., K. Annett, W. S. Laidlaw, D. M. Cahill, M. J. Garkaklis, and L. Zhuang-Griffin. "Long term impacts of Phytophthora cinnamomi infestation on heathy woodland in the Great Otway National Park in south-eastern Australia." Australian Journal of Botany 68, no. 8 (2020): 542. http://dx.doi.org/10.1071/bt20054.
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The significant impacts of the introduced plant pathogen Phytophthora cinnamomi on native Australian vegetation have been well documented, but there is less knowledge of long-term effects. We assessed long-term (26 years) disease progression and impacts on vegetation floristics and structure at a heathy woodland site in the Great Otway National Park, eastern section. Disease progressed dramatically between 1989 and 2005 and by 2015 only 0.08% of the site was non-diseased. There were significant declines in plant species richness and numbers of susceptible species; and increases in percentage cover of resistant sedges and grasses overall, and in cover of Leptospermum continentale (prickly tea-tree) in post-disease areas. There were significant declines of Xanthorrhoea australis (Austral grass-tree), a keystone species that contributes greatly to vegetation structure and fauna habitat. There is an urgent need to map the distribution of P. cinnamomi affected vegetation and identify floristically important non-diseased vegetation in the national park. It is imperative that quarantine of non-infested areas, phosphite application, track closures and vehicle wash-downs be implemented to reduce disease extension and protect the significant biodiversity of the region including species rich heathlands and nationally listed threatened plant and fauna species and their habitats.
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Riley, J. M. "THE RISE AND RISE OF COAL SEAM GAS IN THE BOWEN BASIN." APPEA Journal 44, no. 1 (2004): 647. http://dx.doi.org/10.1071/aj03032.
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The coal seam gas (CSG) industry has been active in Australia for almost three decades, with interest largely focussed on the Bowen and Sydney basins. Sporadic activity has also occurred in a number of other areas including the Galilee, Ipswich, Clarence–Moreton, Gunnedah, Gloucester, and Otway basins to name a few, with significant recent interest shown in the promising Surat Basin. Of these basins it is the Bowen Basin in eastern central Queensland which has continued to shine as the premier coal seam gas province in the country.From humble beginnings in the mid-1970s in the Moura area, CSG from the Bowen Basin now supplies around 20% of Queensland gas demand. Since the start of commercial production from the basin in 1996, production has grown to about 20 PJ per year from five separate fields, with three new fields under construction expected to more than double this volume over the next 2–3 years.The largest contribution to this growth will come from the Comet Ridge region which is proving itself to be a world class CSG deposit. The high-productivity fairway in the south of the region extends over an area about 80 km long and 20 km wide and includes the Tipperary Fairview field, and the Origin Energy Spring Gully project. In the last year proved and probable gas reserves have more than doubled to 1,500 PJ across the fairway, with upside recoverable gas estimated to be 4,700 PJ. The rapid rate of CSG reserves increase in the Bowen Basin demonstrates the key role this industry will play in the eastern Australia gas market.
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Smith, Andrew J., and Stephen J. Gallagher. "The Recent foraminifera and facies of the Bass Canyon: a temperate submarine canyon in Gippsland, Australia." Journal of Micropalaeontology 22, no. 1 (July 1, 2003): 63–83. http://dx.doi.org/10.1144/jm.22.1.63.
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Abstract. This study describes the foraminifera and facies of a large submarine canyon: the Bass Canyon, in the Gippsland Basin off the coast of southeastern Australia. The study incorporates facies analyses and interpretations of three types of foraminiferal distributional data: forms alive at time of collection, recently dead forms and relict forms. Four principle biofacies types occur: (1) middle shelf to shelf-break carbonate sand; (2) oxic upper to middle bathyal carbonate sand and gravel, with abundant bryozoans; (3) reduced oxic middle bathyal carbonate sand and gravel and (4) lower bathyal oxic muddy sand to Globigerina Ooze.Correspondence Analysis of the 61 parameters (percentage abundance of foraminifera and % carbonate) in 36 samples yielded a clear depth-related pattern, although other related parameters such as dissolved oxygen and substrate also exert control on the foraminiferal assemblages.Relict foraminifera are restricted to shelfal depths, shallower than 145 m. This pattern is similar to other shelf regions in Australia, where shelf areas were exposed during the Last Glacial Maximum, reworking shelf facies shallower than 150 m. The distribution of living foraminifera is similar to the distribution of the total assemblage, suggesting that the region has not been significantly mixed by wave, slump or bioturbation processes.The majority of the modern Bass Canyon foraminiferal assemblages are cosmopolitan species, with few (semi-)endemic taxa that are mostly restricted to the shelf. These modern deeper-living forms are more conservative since they evolved in relatively lower stress eutrophic environments than their shallower oligotrophic dwelling contemporaries.The foraminiferal and facies analogues of this study on the Bass Canyon may be used as a modern palaeoenvironmental analyses of the Gippsland and Otway Neogene sedimentary deep-sea successions. This will lead ultimately to a better understanding of the evolution of the basins in southeastern Australia, in an area influenced by the Southern Ocean during the Cenozoic.
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Wang, Hanchen, and Tariq Alkhalifah. "Direct microseismic event location and characterization from passive seismic data using convolutional neural networks." GEOPHYSICS 86, no. 6 (September 9, 2021): KS109—KS121. http://dx.doi.org/10.1190/geo2020-0636.1.
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The ample size of time-lapse data often requires significant event detection and source location efforts, especially in areas such as shale gas exploration regions where a large number of microseismic events are often recorded. In many cases, real-time monitoring and location of these events are essential to production decisions. Conventional methods face considerable drawbacks. For example, traveltime-based methods require traveltime picking of often noisy data, whereas migration and waveform inversion methods require expensive wavefield solutions and event detection. Both tasks require some human intervention, and this becomes a big problem when too many sources need to be located, which is common in microseismic monitoring. Machine learning has recently been used to identify microseismic events or locate their sources once they are identified and picked. We have used a novel artificial neural network framework to directly map seismic data, without any event picking or detection, to their potential source locations. We train two convolutional neural networks (CNNs) on labeled synthetic acoustic data containing simulated microseismic events to fulfill such requirements. One CNN, which has a global average pooling layer to reduce the computational cost while maintaining high-performance levels, aims to classify the number of events in the data. The other network predicts the source locations and other source features such as the source peak frequencies and amplitudes. To reduce the size of the input data to the network, we correlate the recorded traces with a central reference trace to allow the network to focus on the curvature of the input data near the zero-lag region. We train the networks to handle single-, multi-, and no-event segments extracted from the data. Tests on a simple vertical varying model and a more realistic Otway field model demonstrate the approach’s versatility and potential.
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Aouad, Andrew, Randall Taylor, Neil Millar, Robert Meagher, and Deidre Brooks. "Seismic on the edge—the Speculant 3D Transition Zone Seismic Survey." APPEA Journal 52, no. 1 (2012): 327. http://dx.doi.org/10.1071/aj11025.
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The Speculant 3D Transition Zone (TZ) Seismic Survey was acquired by Origin Energy in the Otway Basin, about 30 km east of Warrnambool, Victoria, during November and December 2010. The objective of the survey was to fill a data gap between existing marine and land 3D seismic surveys. Although the survey covered a small surface area, it included part of the Bay of Islands Coastal Park, dairy farms, southern rock lobster fishing grounds and the migration route for the Southern Right Whale. Numerous exclusion zones were required to address a variety of stakeholder concerns, avoid environmentally sensitive areas, combat a physical landscape dominated by 60 m sea cliffs and the large Southern Ocean surf. These access restrictions required the innovative use of modern seismic technology to enable a survey that could simultaneously record onshore and offshore without a physical connection between recording systems. On land a GSR cable-free recording system was used for the first time in Australia, eliminating the need for any line preparation or vegetation clearing. Offshore an ocean bottom cable system was used. The survey employed smaller sources than traditionally used in the region. A 900 in3 generator–injector airgun array was used offshore while a single Vibroseis unit was used on land. This paper shares the lessons learnt during the planning, approval and acquisition of the Speculant Seismic Survey with the steps taken to reduce the operation’s footprint while maintaining data quality.
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Boreham, C. J., J. E. Blevin, I. Duddy, J. Newman, K. Liu, H. M. Middleton, M. K. Macphail, and A. C. Cook. "EXPLORING THE POTENTIAL FOR OIL GENERATION, MIGRATION AND ACCUMULATION IN CAPE SORELL–1, SORELL BASIN, OFFSHORE WEST TASMANIA." APPEA Journal 42, no. 1 (2002): 405. http://dx.doi.org/10.1071/aj01022.
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Given the underexplored nature of the Sorell Basin, offshore Tasmania, the reported presence of oil stains and shows in the Late Cretaceous sequence below 3,000 m in Cape Sorell–1 is seen as encouraging evidence of an effective petroleum system. To investigate the significance of these shows, an integrated palynological, geochemical and burial history analysis of Cape Sorell–1 has been undertaken. New data have been collected on palynology, potential source rocks (biomarker and chemical kinetics), oil migration indicators (quantitative grain fluorescence—QGF, and grains–with–oil– inclusions—GOI) and thermal history parameters (vitrinite reflectance—VR, vitrinite–inertinite reflectance and fluorescence—VRF® and apatite fission track analysis—AFTA®). A synthesis of these analyses has resulted in a model that suggests that the terrestrial organic–rich potential source rocks in Cape Sorell–1 are very labile for hydrocarbon generation and are presently at the initial phase of oil generation. The model also indicates that increasing hydrocarbon generation with time reflects a progressive increase in temperature reaching maximum temperatures at the present–day. According to the model, accelerated rate of oil generation from the Maastrichtian potential source rock interval at ~3,200 m in the lower Sherbrook Group Equivalent occurred at ~48 Ma and is in response to the maximum burial heating rate in the Early Eocene, during rapid deposition of the thick Wangerrip Group Equivalent. This heating event may have been related to gateway opening along the Otway coast and west Tasmanian margin. Although there was a declining heating rate since the Early Eocene, gas and oil may continue to be generated to the present–day at Cape Sorell–1.The low content of mobile oil below sealing facies higher in the section negates a pervasive oil migration phase sourced down–dip from the basin centre, or from older sedimentary sequences below TD in Cape Sorell–1. However, the possibility that Cape Sorell–1 is in a migration shadow cannot be excluded. The restricted areal extent of the depocentre associated with Cape Sorell–1, together with thin, isolated potential source beds at the well site, would indicate the major risk for hydrocarbon occurrences in the local region is limited source rock volume. However, seismic evidence suggests the possible presence of similar facies within the deeper syn–rift succession below TD at Cape Sorell–1. The labile nature of the organic matter would support oil generation and migration at maturities lower and depths shallower than traditionally viewed. This work provides evidence to support a possible oil play from terrestrial source rocks in the Sorell Basin, and may also provide useful insights into recent large offshore gas discoveries to the north in the adjacent Otway Basin.
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GREHAN, JOHN R., and CARLOS G. C. MIELKE. "Evolutionary biogeography and tectonic history of the ghost moth families Hepialidae, Mnesarchaeidae, and Palaeosetidae in the Southwest Pacific (Lepidoptera: Exoporia)." Zootaxa 4415, no. 2 (April 30, 2018): 243. http://dx.doi.org/10.11646/zootaxa.4415.2.2.
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The biogeographic history of Exoporia (Lepidoptera) in the Southwest Pacific is reconstructed for genera and species that show distributional boundaries corresponding to tectonic structures in the region. Correlations with tectonic formations of Mesozoic origin such as the Whitsunday Volcanic Province and Otway-Bass-Gippsland Basin system in Australia, the Vitiaz Fracture Zone in northern Melanesia, and the Western Province-Eastern Province boundary, Waitaki Fault Zone, and Waihemo Fault Zone of New Zealand are presented as evidence of an East Gondwana origin for genera and species before the geological separation of Australia and New Zealand. The correlated boundaries also suggest that many extant species retain at least parts of their original East Gondwana distribution ranges. The presence of Exoporia on the northern Melanesian Arc, New Caledonia, and New Zealand is attributed to the tectonic isolation of these areas when East Gondwana expanded into the Pacific following retreat of the Pacific Plate subduction zone. Local endemism of Mnesarchaeidae in New Zealand is interpreted as the result of an original vicariance from a widespread ancestor (‘Exoporia’) resulting in two allopatric descendants —a narrowly distributed Mnesarchoidea and a widely distributed Hepialoidea. The current overlap of these two groups in New Zealand is explained as the result of subsequent range expansion by the Hepialoidea prior to geological fragmentation of East Gondwana. The potential impact of Cretaceous geography on modern distributions is also considered for Exoporia in southern Africa and northern America. Along with lateral displacement of Exoporia, tectonic processes also contributed to the origin of high elevation endemics through a process of passive tectonic uplift.
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Wilson, B. A., J. G. Aberton, and T. Reichl. "Effects of fragmented habitat and fire on the distribution and ecology of the swamp antechinus (Antechinus minimus maritimus) in the eastern Otways, Victoria." Wildlife Research 28, no. 5 (2001): 527. http://dx.doi.org/10.1071/wr00016.
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This study investigated the distribution, habitat and population dynamics of the swamp antechinus (Antechinus minimus maritimus) in the eastern Otway Ranges. The species has a restricted, disjunct distribution and has been recorded at 25 sites between 1969 and 1999. All sites were located within 7 km of the coast, occurred at altitudes up to 80 m above sea level and within 10 m of a gully. Analysis of landscape site variables identified sun index as being significant in determination of the probability of occurrence of A. minimus. The presence of A. minimus is negatively associated with sun index, occuring at sites that have a southerly aspect and gentle slope. A. minimus was located in a range of structural vegetation including Open Forest, Low Woodland, Shrubland and Hummock Grassland and a number of floristic groups, some characterised by high frequencies of sclerophyll shrubs, others by high frequencies of Pteridium esculentum, hummock grasses and herbaceous species. A. minimus occurs in fragmented, small populations with maximum population densities of 1.1–18 ha–1. Populations at inland sites became extinct after the 1983 wildfire which burnt 41 000 ha. These sites have not been recolonised since, while on the coast the species did not re-establish until 1993–97. One population that is restricted to a narrow coastal strip of habitat is characterised by high levels of transient animals. The species is subject to extinction in the region due to habitat fragmentation, coastal developments and fire. Management actions to secure the present populations and ensure long-term survival of the species in the area are required and include implementation of appropriate fire regimes, prevention of habitat fragmentation, revegetation of habitat, and establishment of corridor habitat.
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Wayne, A. F., B. A. Wilson, and J. C. Z. Woinarski. "Falling apart? Insights and lessons from three recent studies documenting rapid and severe decline in terrestrial mammal assemblages of northern, south-eastern and south-western Australia." Wildlife Research 44, no. 2 (2017): 114. http://dx.doi.org/10.1071/wr16178.
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Context Since European settlement in 1788, much of the Australian terrestrial mammal fauna has declined or become extinct. The pattern of, and reason for, that decline was little documented, and is now difficult to decipher. Many mammal species are still declining, providing (an unfortunate) opportunity to better document the process, identify the causal factors and attempt to redress the problem. Aim We compare trends in mammal abundance reported in three recent longitudinal studies in conservation reserves in Australia. The studies were not established with the intention of documenting mammal decline, but marked simultaneous decline of co-existing species was the most striking feature of their results. Methods Long-term monitoring in Kakadu National Park, Northern Territory (2001–04 and 2007–09), the Upper Warren region of Western Australia (since 1974) and the Great Otway National Park, Victoria (since 1975) principally relied on trapping, but also some spotlighting and sand plots, to document changes and trends in abundance in their respective mammal assemblages. Key results Decline was reported in most mammal species, across taxonomic groups, diets and size classes, but mostly involved species <5500g. The studies differed in their monitoring protocols and varied in the degree to which potential causal factors were monitored, thereby constraining interpretation of the drivers of declines. Inappropriate fire regimes and predation by feral cats are likely contributing factors in at least two study areas, and periods of markedly below-average rainfall are implicated in two areas. Conclusions We conclude the following: (1) conservation reserves in Australia may be failing to maintain at least some elements of the biodiversity that they were established to protect, and substantially enhanced management is required to redress this problem; (2) with current threats, mammal assemblages in Australia may be highly unstable; (3) substantial increase in effective long-term biodiversity monitoring programs in an adaptive management framework is needed; and (4) such monitoring programs will be more insightful if they also monitor factors driving population change. Implications Native mammal species declines and community disassembly may be occurring elsewhere. Long-term monitoring is critical for assessing trends in biodiversity and if done well, it can guide more effective and efficient management to deliver better conservation outcomes.
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Cowley, R., and G. W. O'Brien. "IDENTIFICATION AND INTERPRETATION OF LEAKING HYDROCARBONS USING SEISMIC DATA:A COMPARATIVE MONTAGE OF EXAMPLES FROM THE MAJOR FIELDS IN AUSTRALIA'S NORTHWEST SHELF AND GIPPSLAND BASIN." APPEA Journal 40, no. 1 (2000): 119. http://dx.doi.org/10.1071/aj99008.
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An extensive volume of 3D seismic data over a number of oil and gas fields in Australia's North West Shelf and Gippsland Basin has been examined for evidence of the effects of hydrocarbon migration and/or leakage. For comparative purposes, 2D and 3D data have also been studied over a number of adjacent traps, including dry traps and partially to completely breached accumulations. Fields and traps investigated include Bayu-Undan, Jabiru, Skua, Swift and Tahbilk in the Bonaparte Basin, Cornea in the Browse Basin, North Rankin, Chinook, Macedon, Enfield and Zeewulf in the Carnarvon Basin, and Kingfish in the Gippsland Basin. The principal goal of the study is to provide representative case studies from known fields so that, in undrilled regions, the exploration uncertainties associated with the issues of hydrocarbon charge and trap integrity might be reduced.Direct indicators of hydrocarbon migration and/or leakage are relatively rare throughout the basins studied, though the discoveries themselves characteristically show seismic anomalies attributable to hydrocarbon leakage. The nature and intensity of these hydrocarbon-related seismic effects do, however, vary dramatically between the fields. Over traps such as Skua, Swift, Tahbilk and Macedon, they are intense, whereas over others, for example Chinook and North Rankin, they are quite subtle. Hydrocarbon-related diagenetic zones (HRDZs), which had been identified previously above the reservoir zones of leaky traps within the Bonaparte Basin, have also been recognised within the Browse, Carnarvon, Otway and Gippsland Basins. HRDZs are the most common leakage indicators found and are identified easily via a combination of high seismic amplitudes through the affected zone, time pull-up and degraded stack response of underlying reflectors. In some cases (the Skua and Macedon Fields), the HRDZs actually define the extent of the accumulations at depth.Anomalous, subtle to strong, seismic amplitude anomalies are associated with the majority of the major fields within the Carnarvon Basin. The strength and location of the anomalies are related to a complex interplay between trap type (in particular four-way dip-closed versus fault dependent), top seal capacity, fault seal integrity, and charge history. In some areas within the Carnarvon, Browse and Bonaparte Basins, shallow amplitude anomalies can be related directly to gas chimneys emanating from the reservoir zone itself. In other instances, the continuous migration of gas from the reservoir has produced an assortment of pockmarks, mounds and amplitude anomalies on the present day sea floor, which all provide evidence of hydrocarbon seepage. In the Browse Basin, strong evidence has been found that many of the modern carbonate banks and reefs in the region were initially located over hydrocarbon seeps on the palaeo-seafloor.The examples and processes presented demonstrate that the analysis of hydrocarbon leakage indicators on seismic data can help to better understand exploration risk and locate subtle hydrocarbon accumulations. In mature exploration provinces, this methodology may lead to the identification of subtle accumulations previously left undetected by more conventional methods. In frontier regions, it can help to identify the presence of a viable petroleum system, typically the principal exploration uncertainty in undrilled regions.
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Cooper, G. T. "SEISMIC STRUCTURE AND EXTENSIONAL DEVELOPMENT OF THE EASTERN OTWAY BASIN-TORQUAY EMBAYMENT." APPEA Journal 35, no. 1 (1995): 436. http://dx.doi.org/10.1071/aj94028.
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The Eastern Otway Basin exhibits two near-or-thogonal structural grains, specifically NE-SW and WNW-ESE trending structures dominating the Otway Ranges, Colac Trough and Torquay Embayment. The relative timing of these structures is poorly constrained, but dip analysis data from offshore seismic lines in the Torquay Embayment show that two distinct structural provinces developed during two separate extensional episodes.The Snail Terrace comprises the southern structural province of the Torquay Embayment and is characterised by the WNW-ESE trending basin margin fault and a number of small scale NW-SE trending faults. The Torquay Basin Deep makes up the northern structural province and is characterised by the large scale, cuspate Snail Fault which trends ENE-WSW with a number of smaller NE-SW trending faults present.Dip analysis of basement trends shows a bimodal population in the Torquay Embayment. The Snail Terrace data show extension towards the SSW (193°), but this trend changes abruptly to the NE across a hinge zone. Dip data in the Torquay Basin Deep and regions north of the hinge zone show extension towards the SSE (150°). Overall the data show the dominance of SSE extension with a mean vector of 166°.Seismic data show significant growth of the Crayfish Group on the Snail Terrace and a lesser growth rate in the Torquay Basin Deep. Dip data from the Snail Terrace are therefore inferred to represent the direction of basement rotation during the first phase of continental extension oriented towards the SSW during the Berriasian-Barremian? (146-125 Ma). During this phase the basin margin fault formed as well as NE-SW trending ?transtensional structures in the Otway Ranges and Colac Trough, probably related to Palaeozoic features.Substantial growth along the Snail Fault during the Aptian-Albian? suggests that a second phase of extension affected the area. The Colac Trough, Otway Ranges, Torquay Embayment and Strzelecki Ranges were significantly influenced by this Bassian phase of SSE extension which probably persisted during the Aptian-Albian? (125-97 Ma). This phase of extension had little effect in the western Otway Basin, west of the Sorrel Fault Zone, and was largely concentrated in areas within the northern failed Bass Strait Rift. During the mid-Cretaceous parts of the southern margin were subjected to uplift and erosion. Apatite fission track and vitrinite reflectance analyses show elevated palaeotemperatures associated with uplift east of the Sorell Fault Zone.
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Lockhart, D., and D. Spring. "PESA Australian exploration review 2018." APPEA Journal 59, no. 2 (2019): 493. http://dx.doi.org/10.1071/aj18284.
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Available data for 2018 indicates that exploration activity is on the rise in Australia, compared to 2017, and this represents a second year of growth in exploration activity in Australia. There has been an increase in area under licence by 92 000 km2, reversing the downward trend in area under licence that commenced in 2014. Since 2016, exploratory drilling within Australia has seen a continued upward trend in both the number of wells drilled and the percentage of total worldwide. Onshore, 77 conventional exploration and appraisal wells were spudded during the year. Offshore, exploration and appraisal drilling matched that seen in 2017, with five new wells spudded: two in the Roebuck Basin, two in the Gippsland Basin and one in the North Carnarvon Basin. Almost 1500 km of 2D seismic and over 10 000 km2 of 3D seismic were acquired within Australia during 2018, accounting for 2.4% and 3.9% of global acquisition, respectively. This represents an increase in the amount of both 2D and 3D seismic acquired in Australia compared with 2017. Once the 2017 Offshore Petroleum Acreage Release was finalised, seven new offshore exploration permits were awarded as a result. A total of 12 bids were received for round one of the 2018 Offshore Petroleum Exploration Release, demonstrating an increase in momentum for offshore exploration in Australia. The permits are in Commonwealth waters off Western Australia, Victoria and the Ashmore and Cartier islands. In June 2018, the Queensland Government announced the release of 11 areas for petroleum exploration acreage in onshore Queensland, with tenders closing in February/March 2019; a further 11 areas will be released in early 2019. The acreage is a mix of coal seam gas and conventional oil and gas. Victoria released five areas in the offshore Otway Basin within State waters. In the Northern Territory, the moratorium on fracking was lifted in April, clearing the way for exploration to recommence in the 2019 dry season. With the increase in exploration has come an increase in success, with total reserves discovered within Australia during 2018 at just under 400 million barrels of oil equivalent, representing a significant increase from 2017. In 2018, onshore drilling resulted in 18 new discoveries, while offshore, two new discoveries were made. The most notable exploration success of 2018 was Dorado-1 drilled in March by Quadrant and Carnarvon Petroleum in the underexplored Bedout Sub-basin. Dorado is the largest oil discovery in Australia of 100 million barrels, or over, since 1996 and has the potential to reinvigorate exploration in the region.
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Smith, Andrew J., Stephen J. Gallagher, Malcolm Wallace, Guy Holdgate, Jim Daniels, and Jock Keene. "The Recent temperate foraminiferal biofacies of the Gippsland Shelf: an analogue for Neogene environmental analyses in southeastern Australia." Journal of Micropalaeontology 20, no. 2 (December 1, 2001): 127–42. http://dx.doi.org/10.1144/jm.20.2.127.
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Abstract. This study describes the foraminiferal biofacies of a temperate stenohaline shelf and associated euryhaline marine lakes of Gippsland in southeast Australia. The study incorporates facies analyses and interpretations of three types of foraminiferal distributional data: forms alive at the time of collection, recently dead forms and relict forms. Four principal biofacies types occur: (1) the euryhaline marine Gippsland Lakes silts and sands; (2) inner shelf medium to coarse quartz-rich sands and bioclastic silty sands; (3) medium shelf bryozoan-rich bioclastic silt and silty sand; (4) outer shelf bryozoan- and plankton-rich silts and fine sands.The euryhaline marine Gippsland Lakes silts and sands contain abundant Ammonia beccarii and Eggerella, with minor Quinqueloculina, Elphidium and Discorbinella. The Gippsland inner shelf biofacies (0–50 m depths) consists of medium to coarse quartz-rich sands and bioclastic silty sand. Abundant living, relict and recently dead miliolids occur in the inner shelf with rare planktonic forms. Common planktonic foraminifera, with Cibicides, Parrellina, Elphidium and Lenticulina and relict forms occur in the bryozoan-rich bioclastic silt and silty sand of the Gippsland middle shelf (50–100 m depth). Bryozoan and plankton-rich silts and fine sand occur in the outer shelf to upper slope facies (100–300 m) below swell wave base on the Gippsland Shelf. A diverse fauna with common textulariids, Uvigerina, Bulimina, Anomalinoides and Astrononion and rare relict forms, occurs in this biofacies. Planktonic foraminifera and Uvigerina are most abundant at the shelf break due to local upwelling at the head of the Bass Canyon.Estimates of faunal production rates from live/dead ratios and full assemblage data suggest that the fauna of the Gippsland Shelf has not been significantly reworked by wave and/or bioturbation processes. Most relict foraminifera occur in the inner shelf, with minor relict forms in the middle to outer shelf. This pattern is similar to other shelf regions in Australia, where shelf areas were exposed during Pleistocene lowstand times, principally reworking pre-existing inner to middle shelf faunas. Correspondence analyses of the foraminiferal data yield a clear depth-related distribution of the faunal assemblage data. Most of the modern Gippsland Shelf fauna are cosmopolitan species and nearly a third are (semi-)endemic taxa suitable for regional palaeo-environmental studies. From biostratigraphic studies it is clear that the modern Gippsland foraminiferal assemblage evolved since Early Miocene times, with most elements present by the Late Miocene. Hence, the Recent Gippsland Shelf foraminiferal biofacies distribution is a good analogue for Neogene palaeo-environmental studies in the region. The longer ranging pre-Miocene mixture of epifaunal and infaunal taxa are deeper shelf cosmopolitan forms and are inferred to be more conservative since they evolved in relatively lower stress environments, typifying mesotrophic to eutrophic conditions compared to inner shelf epifaunal forms with ecological niches markedly affected by sea-level and temperature fluctuations in zones of constant wave action, in oligotrophic environments.The foraminiferal and facies analogues of this study on the Gippsland Shelf can be used for palaeo-environmental analyses of the Gippsland and Otway Neogene sedimentary successions. Such improvements will lead ultimately to a better understanding of the evolution of the neritic realm in southeastern Australia, an area facing the evolving Southern Ocean during the Cenozoic.
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Infante L., Pedro, and José Antonio Prado D. "Crecimiento juvenil de 32 procedencias y 203 familias de Eucalyptus globulus ssp. globulus en la zona costera de la VIII Región de Chile." Ciencia & Investigación Forestal 5, no. 2 (July 6, 1991): 251–65. http://dx.doi.org/10.52904/0718-4646.1991.155.
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La supervivencia y desarrollo de 32 procedencias y 203 familias de Eucalyptus globulus ssp. globulus que cubren gran parte de la distribución natural de la especie, se evalúan en un ensayo de procedencias y progenies establecido en la provincia de Arauco, Chile. Veinte meses después de la plantación se encuentran diferencias significativas entre procedencias y familias, tanto en altura como en diámetro. Aún cuando no hay un patrón de variación geográfica bien definido, estos resultados indican que las mejores procedencias corresponden al sudeste de Tasmania, las islas Cape Barren y Flinders, en el estrecho de Bass y Otway, en Victoria. La fuente de semillas local fue superada por 15 procedencias naturales.
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DOUGNAC, C., C. PARDO, K. MEZA, C. ARREDONDO, O. BLANK, P. ABALOS, R. VIDAL, A. FERNANDEZ, F. FREDES, and P. RETAMAL. "Detection ofSalmonella entericain Magellanic penguins (Spheniscus magellanicus) of Chilean Patagonia: evidences of inter-species transmission." Epidemiology and Infection 143, no. 6 (August 22, 2014): 1187–93. http://dx.doi.org/10.1017/s0950268814002052.
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SUMMARYPatagonia in southern South America is among the few world regions where direct human impact is still limited but progressively increasing, mainly represented by tourism, farming, fishing and mining activities. The sanitary condition of Patagonian wildlife is unknown, in spite of being critical for the assessment of anthropogenic effects there. The aim of this study was the characterization ofSalmonella entericastrains isolated from wild colonies of Magellanic penguins (Spheniscus magellanicus) located in Magdalena Island and Otway Sound, in Chilean Patagonia. Eight isolates ofSalmonellawere found, belonging to Agona and Enteritidis serotypes, with an infection rate of 0·38%. Resistance to ampicillin, cefotaxime, ceftiofur and tetracycline antimicrobials were detected, and some of these strains showed genotypic similarity withSalmonellastrains isolated from humans and gulls, suggesting inter-species transmission cycles and strengthening the role of penguins as sanitary sentinels in the Patagonian ecosystem.
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Bernecker, Thomas. "Review of the 2009 offshore petroleum exploration release areas." APPEA Journal 49, no. 1 (2009): 465. http://dx.doi.org/10.1071/aj08031.
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The Australian Government formally releases new offshore exploration areas at the annual APPEA conference. This year, 31 areas plus two special areas in five offshore basins are being released for work program bidding. Closing dates for bid submissions are either six or twelve months after the release date (i.e. 3 December 2009 and 29 April 2010), depending on the exploration status in these areas is and on data availability. The 2009 release areas are located in Commonwealth waters offshore Northern Territory, Western Australia, South Australia and Victoria, comprising intensively explored areas close to existing production as well as new frontiers. As usual, the North West Shelf features very prominently and is complimented by new areas along the southern margin, including frontier exploration areas in the Ceduna Sub-basin (Bight Basin) and the Otway Basin. The Bonaparte Basin is represented by one release area in the Malita Graben, while five areas are available in the Southern Browse Basin in an under-explored area of the basin. A total of 14 areas are being released in the Carnarvon Basin, with eight areas located in the Dampier Sub-basin, three small blocks in the Rankin Platform and three large blocks on the Northern Exmouth Plateau (these are considered a deep water frontier). In the south, six large areas are on offer in the Ceduna Sub-basin and five areas of varying sizes are being released in the Otway Basin, including a deep water frontier offshore Victoria. The special release areas are located in the Petrel Sub-basin, Bonaparte Basin offshore Northern Territory, and encompass the Turtle/Barnett oil discoveries. The 2009 offshore acreage release offers a wide variety of block sizes in shallow as well as deep water environments. Area selection has been undertaken in consultation with industry, the states and Territory. This year’s acreage release caters for the whole gamut of exploration companies given that many areas are close to existing infrastructure while others are located in frontier offshore regions. As part of Geoscience Australia’s Offshore Energy Security Program, new data has been acquired in offshore frontier regions and have yielded encouraging insights into the hydrocarbon prospectivity of the Ceduna-Sub-basin.
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JPT staff, _. "E&P Notes (December 2020)." Journal of Petroleum Technology 72, no. 12 (December 1, 2020): 16–17. http://dx.doi.org/10.2118/1220-0016-jpt.
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China Shale-Gas Field Sets Production Record Sinopec recorded China’s highest daily output of shale gas at 20.62 million cubic meters (Mcm) at its Fuling shale-gas field in Chongqing, China, a key gas source for the Sichuan-East gas pipeline. The first major commercial shale-gas project in China, Fuling has continuously broken records for the shortest gasfield drilling cycle while significantly increasing the drilling of high-quality reservoirs covering more than 3 million m, according to Sinopec. Gasfield production construction was also expanded to raise production capacity. The company said the field maintains a daily output of 20 Mcm, producing an estimated 6.7 Bcm per year. Apache and Total Plan Suriname Appraisals Apache filed appraisal plans for its Maka and Sapakara oil discoveries in block 58 offshore Suriname. The company said another submission is expected for Kwaskwasi, the largest find in the block, by the end of the year. Operations continue for Keskesi, the fourth exploration target. There are plans to drill a fifth prospect at Bonboni in the North-Central portion of the concession. Partner company Total is assuming operatorship of the block ahead of next year’s campaigns. BP Emerges as Sole Bid for Offshore Canada Parcels BP was the only operator to place a bid in the Canada-Newfoundland and Labrador Offshore Petroleum Board (C-NLOPB) Call for Bids NL20-CFB01, which offered 17 parcels (4,170,509 hectares) in the eastern Newfoundland region. The successful bid was for Parcel 9 (covering 264,500 hectares) for $27 million in work commitments from BP Canada Energy Group. Subject to BP satisfying specified requirements and receiving government approval, the exploration license will be issued in January 2021. No bids were received for the remaining 16 parcels, which may be reposted in a future Call for Bids. Criteria for selecting a winning bid is the total amount the bidder commits to spend on exploration of the parcel during the first period of a 9-year license, with a minimum acceptable bid of $10 million in work commitments for each parcel. Beach Energy To Drill Otway Basin Well Beach Energy plans to drill at its Artisan-1 well about 32 km offshore Victoria, Australia, in the Otway basin, before the end of 2021. The well, located on Block Vic/P43, was to be spudded in 1H 2020 but was delayed due to COVID-19. The timeframe for drilling was confirmed by the National Offshore Petroleum Safety and Environmental Management Authority, which also said Beach is keeping open the option to suspend the well and develop it, pending reservoir analysis. Anchors, mooring chains, and surface buoys have already been laid for the well, which is in a water depth of approximately 71 m. The well is expected to take approximately 35–55 days to drill, depending on the final work program and potential operational delays. Diamond Offshore’s semisubmersible Ocean Onyx was contracted for the drilling program. Artisan is the first of Beach’s planned multiwell campaigns, which also include development wells at the Geographe and Thylacine fields. Hess Completes Sale of Interest in Gulf of Mexico Field Hess completed the sale of its 28% working interest in the Shenzi Field in the deepwater Gulf of Mexico (GOM) to BHP, the field’s operator, for $505 million. Shenzi is a six-lease development structured as a joint ownership: BHP (operator, 44%), Hess (28%), and Repsol (28%). The acquisition would bring BHP’s working interest to 72%, adding approximately 11,000 BOE/D of production (90% oil). The sale is expected to close by December 2020. Hess CEO John Hess said proceeds from the sale will help fund the company’s investment in Guyana. Greenland Opens New Offshore Areas Greenland opened three new offshore areas for application of oil and gas exploitation licenses off West Greenland. The areas are Baffin Bay, Disko West, and Davis Strait. The country also said it is working on an oil strategy to reduce geological uncertainty by offering an investment package to companies that engage in its Open Door Procedures. The procedures are a first-mover advantage to remove national oil company Nunaoil, as a carried partner, reducing turnover and surplus royalties. It is estimated to reduce the government take by 51.3% to 40.6%. Shell and Impact Oil & Gas Agree to South Africa Farmout Africa Oil announced Impact Oil & Gas entered into two agreements for exploration areas offshore South Africa. The company has a 31.10% share-holding in Impact, a privately owned exploration company. Impact entered into an agreement with BG International, a Shell subsidiary, for the farm-out of a 50% working interest and operatorship in the Transkei and Algoa exploration rights. Shell was also granted the option to acquire an additional 5% working interest should the joint venture (JV) elect to move into the third renewal period, expected in 2024. Algoa is located in the South Outeniqua Basin, east of Block 11B/12B, containing the Brulpadda gas condensate discovery and where Total recently discovered gas condensate. The Transkei block is northeast of Algoa in the Natal Trough Basin where Impact has identified highly material prospectivity associated with several large submarine fan bodies, which the JV will explore with 3D seismic data and then potential exploratory drilling. Impact and Shell plan to acquire over 6,000 km² of 3D seismic data during the first available seismic window following completion of the transaction. This window is expected to be in the Q1 2022. After the closing of the deal, Shell will hold a 50% interest as the operator and Impact will hold 50%. Impact also entered into an agreement with Silver Wave Energy for the farm-in of a 90% working interest and operatorship of Area 2, offshore South Africa. East and adjacent to Impact’s Transkei and Algoa blocks, Area 2 complements Impact’s existing position by extending the entire length of the ultradeepwater part of the Transkei margin. Together, the Transkei and Algoa Blocks and Area 2 cover over 124,000 km2. Area 2 has been opened by the Brulpadda and Luiperd discoveries in the Outeniqua Basin and will be further tested during 2021 by the well on the giant Venus prospect in ultradeepwater Namibia, where Impact is a partner. Impact believes there is good evidence for this Southern African Aptian play to have a common world-class Lower Cretaceous source rock, similar excellent-quality Apto-Albian reservoir sands, and a geological setting suitable for the formation of large stratigraphic traps. Following completion of the farm-in, Impact will hold 90% interest and serve as the operator; Silver Wave will hold 10%. Petronas Awards Sarawak Contract to Seismic Consortium The seismic consortium comprising PGS, TGS, and WesternGeco was awarded a multiyear contract by Petronas to acquire and process up to 105,000 km2 of multisensor, multiclient 3D data in the Sarawak Basin, offshore Malaysia. The contract award follows an ongoing campaign by the consortium in the Sabah offshore region, awarded in 2016, in which over 50,000 km2 of high-quality 3D seismic data have been acquired and licensed to the oil and gas industry to support Malaysia license round and exploration activity. The Sarawak award will allow for a multiphase program to promote exploration efforts in the prolific Sarawak East Natuna Basin (Deepwater North Luconia and West Luconia Province). The consortium is planning the initial phases and is engaging with the oil and gas industry to secure prefunding ahead of planned acquisition, covering both open blocks and areas of existing farm-in opportunities. Total Discovers Second Gas Condensate in South Africa Total made a significant second gas condensate discovery on the Luiperd prospect, located on Block 11B/12B in the Outeniqua Basin, 175 km off the southern coast of South Africa. The discovery follows the adjacent play-opening Brulpadda discovery in 2019. The Luiperd-1X well was drilled to a total depth of about 3,400 m and encountered 73 m of net gas condensate pay in well-developed, good-quality Lower Cretaceous reservoirs. Following a coring and logging program, the well will be tested to assess the dynamic reservoir characteristics and deliverability. The Block 11B/12B covers an area of 19,000 km2, with water depths ranging from 200 to 1800 m. It is operated by Total with a 45% working interest, alongside Qatar Petroleum (25%), CNR International (20%), and Main Street, a South African consortium (10%). The Luiperd prospect is the second to be drilled in a series of five large submarine fan prospects with direct hydrocarbon indicators defined utilizing 2D and 3D seismic data. BP Gas Field Offshore Egypt Begins Production BP started gas production from its Qattameya gasfield development offshore Egypt in the North Damietta offshore concession. Through BP’s joint venture Pharaonic Petroleum Company working with state-owned Egyptian Natural Gas Holding Co., the field, which is expected to produce up to 50 MMcf/D, was developed through a one-well subsea development and tieback to existing infrastructure. Qattameya, whose discovery was announced in 2017, is located approximately 45 km west of the Ha’py platform, in 108 m of water. It is tied back to the Ha’py and Tuart field development via a new 50-km pipeline and connected to existing subsea utilities via a 50-km umbilical. BP holds 100% equity in the North Damietta offshore concession in the East Nile Delta. Gas production from the field is directed to Egypt’s national grid.
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Bernecker, Thomas. "A petroleum geological overview of the 2013 offshore acreage release for petroleum exploration." APPEA Journal 53, no. 1 (2013): 69. http://dx.doi.org/10.1071/aj12007.
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The Australian Government formally releases new offshore exploration areas at the annual APPEA conference. The previous two releases were characterised by several large, gazetted areas in underexplored regions, a trend that is maintained this year with several frontier areas comprising more than 100 graticular blocks on offer. The recent uptake of new exploration permits in the Bight Basin, the offshore North Perth Basin, and the Roebuck Basin indicates a continuing strong industry interest in offshore frontier exploration. A total of 31 areas in 13 geological provinces are formally released in 2013, and work program bids are invited for two rounds closing on 21 November 2013, and 22 May 2014. Area gazettal was, again, well supported by industry nominations. The areas on offer are represented by an even mix of shallow and deepwater areas, as well as by areas close and distant to previous discoveries and producing fields. The Northern Carnarvon, Browse, and Bonaparte basins dominate new exploration opportunities in the 2013 release, while only four areas were gazetted in the North Perth, Otway, and Gippsland basins. These also deserve attention as they have exploration potential in underexplored parts of the basins and offer opportunities to test new play concepts. Data coverage varies from being excellent in more mature areas to sparse in underexplored areas such as the North Perth Basin. The Australian Government continues to assist offshore exploration activities by providing free access to a wealth of open-file geological and geophysical data.
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Salgado, David, Peter T. Martin, Abhisek Mudgal, and Rafael M. Aldrete. "Calibration methodology for microscopic traffic simulation models of land ports of entry along the US–Mexico border." International Journal of Modeling, Simulation, and Scientific Computing 11, no. 03 (June 2020): 2050019. http://dx.doi.org/10.1142/s1793962320500191.
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Non-commercial Land Ports of Entry (LPOEs) are unique transportation facilities controlling the ingress and egress of passenger vehicles from Mexico to the United States and vice versa. The calibration of microscopic traffic simulation models of non-commercial LPOEs requires a deep understanding of operational processes and driving behavior at these facilities. This paper provides a methodology to guide modelers in calibrating microscopic traffic simulation models of non-commercial LPOEs. The methodology establishes a common framework for modeling operational processes and traffic operations. Moreover, the methodology includes the value of four state variables that characterizes operations of passenger vehicles at non-commercial LPOEs. These variables are speed, acceleration, deceleration, and headway. The authors evaluated this methodology using the Otay Mesa non-commercial LPOE as a case study. Results showed that this methodology could be potentially used to model non-commercial LPOEs along the US–Mexico border and other border regions worldwide.
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Bernecker, Thomas. "Geological overview of the 2011 offshore acreage release for petroleum exploration." APPEA Journal 51, no. 1 (2011): 7. http://dx.doi.org/10.1071/aj10002.
Full textAbstract:
The Australian Government formally releases new offshore exploration areas at the annual APPEA conference. In 2011, 29 areas in eight offshore basins are being released for work program bidding. Closing dates for bid submissions are either six or 12 months after the release date (i.e. 13 October 2011 and 12 April 2012)–this depends on the exploration status in these areas and on data availability. The 2011 Release is the largest since the year 2000 with all 29 areas located in Commonwealth waters offshore NT, WA, Victoria and Tasmania, covering about 200,000 km2. The producing hydrocarbon provinces of the Carnarvon, Otway and Gippsland basins are represented by gazettal blocks that are located close to existing infrastructure and are supported by extensive open file data-sets. Other areas that are close to known oil and gas discoveries lie in the Caswell Sub-basin (eastern Browse Basin) and on the Ashmore Platform (northwestern Bonaparte Basin). A particular aspect of the 2011 release is provided by 13 areas in under-explored regions offshore NT and WA–all of which range from 100–280 graticular blocks in size. These areas, located in the Money Shoal, outer Browse, Roebuck, northeastern Carnarvon, Southern Carnarvon and North Perth basins, offer new opportunities for data-acquisition and regional exploration. The release of three large areas in the Southern Carnarvon and North Perth basins is supported by new data acquired and interpreted by Geoscience Australia as part of the Offshore Energy Security Program, which selected results are being presented at this year’s conference.