The upper Permian to Lower Triassic sedimentary succession in the southern Bonaparte Basin represents an extensive marginal marine depositional system that hosts several gas accumulations, including the Blacktip gas field that has been in production since 2009. Development of additional identified gas resources has been hampered by reservoir heterogeneity, as highlighted by preliminary results from a post drill analyses of wells in the study area that identify reservoir effectiveness as a key exploration risk. The sedimentary succession that extends across the Permian–Triassic stratigraphic boundary was deposited during a prolonged marine transgression and shows a transition in lithofacies from the carbonate dominated Dombey Formation to the siliciclastic dominated Tern and Penguin formations. Recent improvements in chronostratigraphic calibration of Australian biostratigraphic schemes, spanning the late Permian and Early Triassic, inform our review of available palynological data and re-interpretation and infill sampling of well data. The results provide a better resolved, consistent and up-to-date stratigraphic scheme, allowing an improved understanding of the timing, duration, and distribution of depositional environments of the upper Permian to Lower Triassic sediments across the Petrel Sub-basin and Londonderry High. <b>Citation:</b> Owens R., Kelman A., Khider K., Iwanec J., Bernecker T. (2022) Addressing exploration uncertainties in the southern Bonaparte Basin: enhanced stratigraphic control and post drill analysis for upper Permian plays. <i>The APPEA Journal</i> 62, S474-S479

Geoscience Australia has undertaken a regional seismic mapping study that extends into the frontier deep-water region of the offshore Otway Basin. This work builds on seismic mapping and petroleum systems modelling published in the 2021 Otway Basin Regional Study. Seismic interpretation spans over 18 000 line-km of new and reprocessed data collected in the 2020 Otway Basin seismic program and over 40 000 line-km of legacy 2D seismic data. Fault mapping has resulted in refinement and reinterpretation of regional structural elements, particularly in the deep-water areas. Structure surfaces and isochron maps highlight Shipwreck (Turonian–Santonian) and Sherbrook (Campanian–Maastrichtian) supersequence depocentres across the deep-water part of the basin. These observations will inform the characterisation of petroleum systems within the Upper Cretaceous succession, especially in the underexplored deep-water region. Presented at the 2022 Australian Petroleum Production & Exploration Association (APPEA)

We present a new geological map of Warrumbungle Volcano created from volcanic facies field mapping, new geophysical, geochemical, and geochronological data as well as data from previous studies. Field mapping and petrography defined 19 volcanic and 2 mixed volcanic-sedimentary facies. Facies identification and distribution in conjunction with geochemical analyses indicate an early shield-forming phase of predominantly mafic and intermediate lavas and pyroclastic deposits, and minor felsic lavas deposited on an irregularly eroded basement of Surat and Gunnedah basin rocks. The shield was subsequently intruded by felsic intermediate to felsic magmas that formed dykes and other intrusions including possible cryptodomes, and also erupted as lava domes and block-and-ash-flow deposits. A radial dyke swarm cross-cuts most units, although is concentrated within basement sandstone surrounding the central area of the volcano, suggesting late inflation accompanied by dyke emplacement. Geochemistry indicates differentiation of a single although repeatedly recharged alkaline magmatic suite. Fractionation of olivine, Ti-magnetite and clinopyroxene occurred in mafic magmas, and after reaching 62 wt% SiO2 crystallisation of apatite and alkali feldspar took place. A new U-Pb zircon SHRIMP magmatic crystallisation age of 16.25 +/- 0.12 Ma on a felsic block-and-ash flow deposit is in agreement with the recalculated 40Ar/39Ar isochron dates of previous workers. Based on our mapping and the use of volcanic facies to define mappable units, we recommend the previous Warrumbungle Volcanics be elevated from formation to group status and renamed the Warrumbungle Volcanic Complex.

One page article discussing aspects of Australian stratigraphy; this article discusses the issues to consider when reviewing and/or revising a unit or the stratigraphy of an area.

part-page article on stratigraphic issues

One page article discussing aspects of Australian stratigraphy; this article is about the need for more unit definitions.

This Gunnedah Basin dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus. The Gunnedah Basin is an intracratonic, sedimentary basin in northern NSW. It forms the middle section of the greater Sydney-Gunnedah-Bowen Basin system and mainly consists of Permian and Triassic sedimentary rocks resting on Late Carboniferous to Early Permian volcanics. The Gunnedah Basin is overlain by the Surat Basin and the younger alluvial sediments associated with modern and ancient river systems. The Gunnedah Basin is not considered a single well-connected aquifer, rather a series of porous rock aquifers separated by several non-porous or poorly conductive layers. The Lachlan Fold Belt forms what is thought to be an effective basement although little information is known of its hydrogeological properties. All units of the Gunnedah Basin are of low permeability and significantly lower hydraulic conductivity than the overlying alluvial aquifers. Most of the groundwater resources in the area are extracted from either the overlying Surat Basin or younger alluvial aquifers. There is relatively little groundwater sourced from the aquifers of the Gunnedah Basin, except in areas where the overlying aquifers do not occur. The most viable groundwater source in the Gunnedah Basin are the more porous aquifers of the Triassic sequence.

This Sydney Basin dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus. The Sydney Basin, part of the Sydney–Gunnedah–Bowen basin system, consists of rocks dating from the Late Carboniferous to Middle Triassic periods. The basin's formation began with extensional rifting during the Late Carboniferous and Early Permian, leading to the creation of north-oriented half-grabens along Australia's eastern coast. A period of thermal relaxation in the mid Permian caused subsidence in the Bowen–Gunnedah–Sydney basin system, followed by thrusting of the New England Orogen from the Late Permian through the Triassic, forming a foreland basin. Deposition in the basin occurred in shallow marine, alluvial, and deltaic environments, resulting in a stratigraphic succession with syn-depositional folds and faults, mostly trending north to north-east. The Lapstone Monocline and Kurrajong Fault separate the Blue Mountains in the west from the Cumberland Plain in the central part of the basin. The Sydney Basin contains widespread coal deposits classified into geographic coalfield areas, including the Southern, Central, Western, Newcastle, and Hunter coalfields. These coalfields are primarily hosted within late Permian strata consisting of interbedded sandstone, coal, siltstone, and claystone units. The coal-bearing formations are grouped based on sub-basins, namely the Illawarra, Tomago, Newcastle, and Wittingham coal measures, underlain by volcanic and marine sedimentary rocks. Deposition within the basin ceased during the Triassic, and post-depositional igneous intrusions (commonly of Jurassic age) formed sills and laccoliths in various parts of the basin. The maximum burial depths for the basin's strata occurred during the early Cretaceous, reaching around 2,000 to 3,000 metres. Subsequent tectonic activity associated with the Tasman Rift extension in the Late Cretaceous and compressional events associated with the convergence between Australia and Indonesia in the Neogene led to uplift and erosion across the basin. These processes have allowed modern depositional environments to create small overlying sedimentary basins within major river valleys and estuaries, along the coast and offshore, and in several topographic depressions such as the Penrith, Fairfield and Botany basins in the area of the Cumberland Plain.

This Northern Australian Fractured Rock Province dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus. The Northern Australian Fractured Rock Province is a hydrogeological entity defined for this study, building upon earlier national-scale hydrogeological research. Australia's geological development was predominantly from west to east, with Archean rocks in the west, Proterozoic rocks in central Australia, and Phanerozoic rocks in the east. The North Australian Craton (NAC) is a significant tectonic element underlying 80% of the Northern Territory and extending to parts of Western Australia and northern Queensland, making up the core of the Northern Australian Fractured Rock Province. The NAC primarily consists of Paleoproterozoic rocks overlying Neoarchean basement. It is surrounded by Proterozoic terranes, including the Musgrave, Warumpi, and Paterson orogens to the south and south-west, the Terra Australis Orogen in the east, and the Western Australian Craton in the west. The Northern Australian Fractured Rock Province includes approximately twelve geological regions of mostly Proterozoic age, such as the Kimberley Basin, Speewah Basin, and Tanami Orogen, among others. Additionally, the province is partially overlain by the Kalkarindji Province, characterized by volcanic rocks. This widespread basaltic province serves as the basement for several significant sedimentary basins in northern Australia, including the Wiso, Ord, Bonaparte, Daly, and Georgina basins. In summary, the Northern Australian Fractured Rock Province is a hydrogeological region defined by combining various Proterozoic geological regions, mainly situated within the North Australian Craton. It is bounded by other Proterozoic terranes and covered in part by the Kalkarindji Province, which consists of volcanic rocks and forms the basement for several key sedimentary basins in northern Australia. Understanding this province is crucial for evaluating the hydrogeological characteristics and geological history of the region.

This Officer Basin dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus. The Officer Basin is one of Australia's largest intra-cratonic sedimentary basins, spanning approximately 525,000 square kilometres. It contains a thick sedimentary sequence, ranging up to 10,000 m in depth, composed of rocks from the Neoproterozoic to Late Devonian periods. The basin features diverse depositional environments, including marine and non-marine siliclastic and carbonate units, evaporites, and minor volcanic deposits. The Neoproterozoic succession exhibits a range of depositional settings, including pro-delta to shelf, fluvial to shallow marine, lagoonal, glacial, and aeolian systems. The Cambrian to Ordovician sequence reveals evidence of fluvial, shallow marine, aeolian, sabkha to playa, and lacustrine settings. Volcanic rocks occur sporadically within the sequence, like the Cambrian Table Hill Volcanics in WA and the Neoproterozoic Cadlareena Volcanics in SA. The Officer Basin is considered a remnant of the larger Centralian Superbasin that formed during the Neoproterozoic, covering a vast region in central Australia. The Centralian Superbasin formed as a sag basin during the Tonian, accumulating fluvial, marine, and evaporitic sediments, followed by Neoproterozoic glacial deposits. The long-lasting Petermann Orogeny affected the earlier depositional systems, with extensive uplift along the northern margin of the basin leading to deposition of widespread fluvial and marine siliciclastic and carbonate sediments spanning the terminal Proterozoic to Late Cambrian. The Delamerian Orogeny renewed deposition and reactivated existing structures, and promoted extensive basaltic volcanism in the central and western regions of the basin. Later events are a poorly understood stage, though probably involved continued deposition until the Alice Springs Orogeny uplifted the region, terminating sedimentation in the Late Ordovician or Silurian. A suspected Late Devonian extensional event provided space for fluvial siliciclastic sediment deposition in the north-east. Today, the Officer Basin features four distinct structural zones: a marginal overthrust zone along the northern margin, a zone with rupturing by salt diapirs across the main depositional centre, a central thrusted zone, and a broad gently dipping shelf zone that shallows to the south.