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This paper presents the results of a small number of dates from sand samples collected at building sites in the eastern suburbs of Sydney. OSL ages of well-sorted, quartz sand ranges from 31 to 24 ka from within well-developed podzol soil profiles within a metre of the surface. The source of this sand appears to be from the east off the inner continental shelf during a period just prior to the maximum of the Last Glacial Maximum (LGM, Marine Isotope Stage 2) when sea-level was approximately 70-90 m below present level. During a later phase of the LGM, there is evidence from other coastal sites in central NSW and Gippsland, Victoria, that the dominant wind was from the west consistent with evidence from arid and semiarid Australia. Dune orientations in northern NSW into Queensland and other evidence at this time appear to reflect winds from the southeast quadrant. This study highlights the existence of a potential pivot area in dominant wind direction during the LGM between sustained westerly flow in southern area including Victoria and northeast Tasmania and southeast flow of northern NSW into Queensland. In central NSW, the circulation switched from easterly in Stage 2 to westerly as the glacial stage intensified in the LGM sometime after ca 25 ka. [ABSTRACT FROM AUTHOR]

Mineral matter in coals has been found to host valuable elements including germanium, lithium and rare-earth elements (REE), but such content of Australian coals remains under-explored. The aim of this paper is to provide a proof-of-concept study that determines elemental concentrations in the mineral matter of the high-ash, Fort Cooper Coal Measures (FCCM), Bowen Basin, Queensland. Coal in the FCCM has good coking properties but has not been extensively explored owing to its high ash content. This study performs a preliminary assessment of the elements from the coal portion that would typically become waste after washing or combustion. Given that the needs for industrial extraction methods will change over time, cataloguing and documenting the elemental composition of coal may assist future development of multiple products for the benefit of both the coal and mineral industries. This preliminary study has revealed similar elevations of REE and higher-than-average crustal concentrations of lithium, bismuth and scandium in some of the samples. Further analyses will be required on a larger dataset to better understand elemental associations and explore spatial patterns of elemental content that may indicate localised enrichments. Understanding the potential of valuable elements in the FCCM may stimulate interest in multiple-product-coal (or elemental-coal) mining in this under-exploited resource and further encourage the reduction of waste from other Australian coals at the wash-plant stage. [ABSTRACT FROM AUTHOR]

This paper describes the purpose, design and implementation of a new regional-scale geodetic network that has been installed in the Surat Basin, Queensland, and completed in November 2014. The network incorporates 65 survey marks and 40 radar corner reflectors to enable the combination of Global Navigation Satellite System measurements with remotely sensed surface deformation maps derived using the Interferometric Synthetic Aperture Radar technique. The combination of these geodetic techniques in this region will bring an enhanced understanding of how resource extraction affects the ground surface. [ABSTRACT FROM PUBLISHER]

Northeast Queensland contains multiple slices of mafic–ultramafic units, strung out along regional faults that mark major tectonic boundaries. One such complex is the Cowley Ophiolite Complex, which is situated along the Russell-Mulgrave Fault. The Cowley Ophiolite Complex is a differentiated mafic–ultramafic complex composed of gabbro, chlorite schist, anthophyllite schist and serpentinite. We interpret that the alteration assemblages observed throughout the Cowley Ophiolite Complex reflect an amphibolite facies metasomatic overprint within a supra-subduction zone setting. This interpretation is consistent with geochemical discrimination of the gabbro, and chromite grains from the anthophyllite schist. The Cowley Ophiolite Complex records a higher metamorphic grade than the surrounding Hodgkinson Formation, and we interpret this to reflect the allochthonous structural setting of the complex, positioned along an ancient subduction margin. This subduction margin is represented today by the Russell-Mulgrave Fault. Metasomatism and emplacement of the complex probably pre-dated deposition of the Mossman Orogen's active margin successions. Our interpretation of an active subduction complex, which pre-dated the formation of the Mossman Orogen, suggests that the Russell-Mulgrave Fault is a Paleozoic, continental suture zone. The Cowley Ophiolite Complex presents little indication of economic mineralisation; however, much of the complex remains unexplored. The Cowley Ophiolite Complex is a differentiated, mafic–ultramafic complex formed within a supra-subduction zone setting. Emplacement of the Cowley Ophiolite Complex, along the Russell-Mulgrave Fault, pre-dated the formation of the Hodgkinson Province. The Russell-Mulgrave Fault represents an ancient subduction margin, and is interpreted as a Paleozoic, continental suture zone. [ABSTRACT FROM AUTHOR]

Detrital zircon U–Pb age patterns in sandstones from the Triassic–Cretaceous Clarence-Moreton Basin, eastern New South Wales and Queensland, unexpectedly reveal sediment sources overwhelmingly dominated (>70%) by Precambrian–Cambrian zircons, with virtually no input, as was anticipated, from the nearby Carboniferous, Permian or Triassic magmatic arcs and contemporary accretionary wedge associated with the New England Orogen. Some rare, youngest zircons (<5%) are mostly contemporaneous with the estimated depositional age. The older, reworked zircon populations can only be acquired by postulating either (1) an Australian provenance by long overland sediment pathways from the interior to the west, during one or more transport cycles, perhaps from within the Thomson Orogen, and then bypassing or crossing the New England Orogen without any local contribution from that sector or (2) a North Zealandia provenance with a shorter transport distance from a postulated basement block to the east, within the Northern Lord Howe Rise and Kenn Plateau. This would comprise late Mesoproterozoic (1200–1000 Ma) and late Neoproterozoic–Cambrian (700–500 Ma) igneous and metamorphic complexes, similar to that proposed in South Zealandia. Triassic to Jurassic Clarence-Moreton Basin sedimentary rocks have provenances unlike their hinterland time-correlates in New South Wales and Queensland. The latter better share similarities with those in Murihiku Terrane, North Island, New Zealand. The provenance of Clarence-Moreton sediments is similar to that of time-correlates in New Caledonia, and it is postulated that they share a source region on the northern Lord Howe Rise or Kenn Plateau. [ABSTRACT FROM AUTHOR]

The upper Paleozoic–lower Mesozoic strata in the northeastern Galilee Basin are important for their hydrocarbon and groundwater potential; however, despite numerous previous investigations, the nature of this stratigraphic interval remains enigmatic. This study integrates lithostratigraphy, palynology and U–Pb zircon geochronology of well-exposed Permian and Triassic sedimentary rocks and nearby stratigraphic cores from the Hughenden district to determine their maximum depositional ages and then revises the stratigraphy where necessary. The newly defined Galah Tuff Bed was discovered at the top of the Betts Creek beds in Porcupine Gorge and was dated at 251.9 ± 3 Ma. This provides an important age constraint for the Betts Creek beds and is a tie-point for correlations with coeval units in the adjacent Bowen Basin and the Sydney and Gunnedah basins to the southeast. The Galah Tuff Bed is interpreted to correlate with the Yarrabee Tuff in the Bowen Basin. Unconformably overlying the Betts Creek beds is a newly recognised stratigraphic unit, defined herein as the Porcupine Gorge Formation. Detrital zircon maximum depositional ages and palynology indicate a significant depositional hiatus of up to 20 million years between the Betts Creek beds and Porcupine Gorge Formation. The hiatus indicates that the lower part of the Porcupine Gorge Formation is at least upper Middle Triassic, whereas the upper part of the unit extends into the Late Triassic. This age also constrains the overlying Warang Sandstone, which is considerably younger locally than previously reported and is likely diachronous across the northeastern Galilee Basin. An integrated lithostratigraphy, palynology and U–Pb detrital zircon geochronology methodology is applied to the Permian–Triassic succession the northeastern Galilee Basin. Two new stratigraphic units were recognised: the upper Permian Galah Tuff Bed (251.9 ± 3 Ma) and the late Middle–Late Triassic Porcupine Gorge Formation (238.7 ± 3 Ma). The Galah Tuff Bed, correlative of the Yarrabee Tuff in the Bowen Basin, is evidence for widespread volcanism in the late Permian. The age of the Porcupine Gorge Formation indicates diachroneity of the Triassic succession in the Galilee Basin, warranting further examination. [ABSTRACT FROM AUTHOR]

The transition between the North Australian Craton and the Thomson Orogen in the area south of the Mount Isa terrane lies under cover and is a critical element in interpretation of the nature of the Tasmanides. The location of the boundary between these domains is controlled by potential field results; the gravity and magnetic signatures are most sensitive to shallow structure, and so there is little information on structure at depth. Full-crustal reflection profiling crosses the boundary in a few locations but does not provide areal coverage. A deployment of 79 passive seismic stations spanning from southern Queensland into the Mount Isa terrane (AQT experiment) is exploited to examine the variations in crustal thickness and the nature of crustal structure across an area with no prior sampling. The analysis exploits the autocorrelation of the seismic signals that extracts the reflection response from the transmitted signals recorded at the surface, which can be migrated to provide an image of structure at depth. The combination of the active and passive seismic results and other geophysical data indicates that the structure of the northern and central Thomson Orogen is relatively homogeneous with a highly reflective, and magnetic, lower crust suggesting a common substrate across the region. The crust thickens and changes character in the North Australian Craton with variations under cover that can be linked to the areas of exposure. There is a zone approximately 100 km wide that separates the characteristic seismic signatures of the two domains indicating reworking at the craton margin. A combination of passive and active seismic imaging sheds light on the transition from the Thomson Orogen to the North Australian Craton. The north central Thomson Orogen shows a consistent reflection character with a strong band of lower crustal reflectivity. The North Australian Craton shows seismic domains with varying character of reflectivity and crustal thickness. A transition zone about 100 km wide separates the distinctive styles of crustal architecture. [ABSTRACT FROM AUTHOR]

Earthquakes are relatively rare in Queensland. Nevertheless, since European settlement, most parts of the state's east coast have felt the impacts of several moderate to high-magnitude events. Knowledge of seismic activity in Queensland is limited owing to sparse historical seismograph coverage, and the relatively short period (ca 1825 onwards) for which records are available. Previously published compilations of observational records for several high-magnitude historical earthquakes and their effects on local communities are incomplete. The National Library of Australia Trove newspaper collection and newspaper microfilm records were used to document 12 moderate–high-magnitude earthquakes that impacted major population centres in Queensland between 1879 and 1958, before the establishment of effective seismic monitoring. The Trove newspaper collection facilitates access to details on the timing, duration and intensity of events, and the damage caused for many locations where these earthquakes were felt. Newspaper reports for the 12 earthquakes were used to define their regions of impact and a re-evaluation of felt radii, epicentre locations and magnitudes against previously published interpretations. The Trove records are consistent with existing interpretations for the Gayndah 1883, Atherton Tablelands 1928, Bundaberg 1918, Gayndah 1935 and Cairns 1958 events. In contrast, previously published interpretations for the Townsville 1879, Cairns 1896, Mundubbera 1910, Coalstoun Lakes/Kilcoy 1913, Ravenswood 1913, Daintree 1942 and Atherton 1950 earthquakes are not consistent with Trove records, which facilitate improved estimates of epicentre locations and magnitudes. This study has identified and documented three earthquakes in southern Queensland previously unrecognised in the seismological literature that impacted Degilbo in ca 1873, Nanango in 1876 and Toowoomba in 1877. Inconsistencies were found between data on an event that impacted Toowoomba in 1875 and Trove records. This review demonstrates the usefulness of the Trove archive to better identify and document the attributes and impacts of historical earthquakes. Newspapers in the Trove archive are a useful source of information on historical earthquakes. Information from the Trove archive can be used to re-evaluate interpretations of historical earthquakes and discover previously unidentified earthquake events. The nature of historical buildings influenced the effects and the amount of damage caused by historical earthquakes in Queensland. [ABSTRACT FROM AUTHOR]

This study presents two chemical abrasion-thermal ionisation mass spectrometry (CA-TIMS) U–Pb zircon ages from tuffs as well as palynostratigraphic results from the embracing sedimentary succession of the Orallo Formation, Surat Basin, Queensland. Samples were taken from two Geological Survey of Queensland (GSQ) stratigraphic holes, GSQ DRD 26 and GSQ Roma 2. Palynological results assign the upper part of the Orallo Formation to the lower part of the Ruffordiaspora australiensis Interval Zone rather than the upper part of this zone as previously indicated. A late Valanginian isotopic date of 134.38 ± 0.04 Ma from GSQ DRD 26 and an early Hauterivian date of ≤132.46 ± 0.36 Ma from GSQ Roma 2 give the Orallo Formation a Berriasian?/Valanginian–Hautevarian age, rather than the previously inferred Berriasian–Valanginian age determined without any geochronological control. Additionally, when combined with previously published geochronological dates from the Westbourne Formation, these ages suggest that, in the Surat Basin succession, the Jurassic–Cretaceous boundary most likely lies within the Gubberamunda Sandstone. Two U–Pb CA-TIMS ages of 134.38 ± 0.04 Ma and ≤132.46 ± 0.36 Ma have been found, based on zircons extracted Orallo Formation tuffs. Sediments surrounding the two tuffs the zircons were extracted from yielded palynofloras assignable to the lower part of the Ruffordiaspora australiensis Interval Zone. These dates, combined with earlier work, show the Orallo Formation to be of Berriasian?/Valanginian–Hautevarian age. [ABSTRACT FROM AUTHOR]

The Drummond Basin of central Queensland preserves a large-volume succession of little studied, predominantly fluviatile, coarse-grained sedimentary rocks of mid-Mississippian age. The stratigraphy of the basin has been subdivided into three sedimentary cycles. The Cycle 1/Cycle 2 boundary records a distinct, but poorly understood change in provenance from a volcanic-dominated succession related to initial basin rifting (Cycle 1) to a quartz-rich, craton-derived succession (Cycle 2). Cycle 3 has been thought to mark a resumption of intrabasinal volcanism and related sedimentation. The purpose of this study was to enhance the understanding of the basin-wide siliciclastic sedimentation of Cycles 2 and 3, and causes for the changes in sediment provenance. This objective was achieved by constraining large-scale spatial and temporal depositional trends and investigating sediment transport pathways into and through the basin. Petrographic, QFL, paleocurrent and conglomerate clast analyses were undertaken. The observations presented here have several implications relevant to understanding the stratigraphy of the Drummond Basin and regional tectonic events at this time. Cycle 3 is revised here primarily to be a continuation of Cycle 2-style basement-derived sedimentation, rather than recording a resumption of volcanism in the area, as per prevailing models. Quartz-rich sedimentation in the Drummond Basin was, therefore, more long-lived than previously envisaged, and once established, was not significantly disrupted by volcanism. Cycle 2 formation thicknesses appear highly variable across the basin. This is unlikely to be a result of pre-existing rift-related topography as suggested in previous models. The thickness variations are more likely related to sediment bypassing and post-depositional deformation in the area. The distinctive coarse-grained, relatively quartz-rich sedimentation of Cycles 2 and 3 is unusual in its volume and extent. The sediment was transported into the basin from its southern/southwestern margin, implying long-distance transport and extrabasinal sediment supply. While the specific source terrain(s) remain unknown, one plausible tectonic driver was far-field influence of the intraplate Alice Springs Orogeny. [ABSTRACT FROM AUTHOR]

The New England Orogen (NEO), the youngest of the orogens of the Tasmanides of eastern Australia, is defined by two main cycles of compression–extension. The compression component involves thrust tectonics and advance of the arc towards the continental plate, while extension is characterised by rifting, basin formation, thermal relaxation and retreat of the arc towards the oceanic plate. A compilation of 623 records of U–Pb zircon geochronology rock ages from Geoscience Australia, the geological surveys of Queensland and New South Wales and other published research throughout the orogen, has helped to clarify its complex tectonic history. This contribution focuses on the entire NEO and is aimed at those who are unfamiliar with the details of the orogen and who could benefit from a summary of current knowledge. It aims to fill a gap in recent literature between broad-scale overviews of the orogen incorporated as part of wider research on the Tasmanides and detailed studies usually specific to either the northern or southern parts of the orogen. Within the two main cycles of compression–extension, six accepted and distinct tectonic phases are defined and reviewed. Maps of geological processes active during each phase reveal the centres of activity during each tectonic phase, and the range in U–Pb zircon ages highlights the degree of diachronicity along the length of the NEO. In addition, remnants of the early Permian offshore arc formed during extensive slab rollback, are identified by the available geochronology. Estimates of the beginning of the Hunter-Bowen phase of compression, generally thought to commence around 265 Ma are complicated by the presence of extensional-type magmatism in eastern Queensland that occurred between 270 and 260 Ma. [ABSTRACT FROM AUTHOR]

The Toomba flow is the youngest flow of the Nulla volcanic province, located in north Queensland. This 120 km-long flow has yielded a published 40Ar/39Ar age of 21,000 ± 3000 years. In contrast, seven published conventional radiocarbon (14C) analyses of carbon-bearing material beneath the flow yielded radiocarbon ages of 16,000 to <2500 BP. These radiocarbon ages are younger than the 40Ar/39Ar age, potentially due to contamination of the charcoal by younger carbon that was not removed by the acid-base pre-treatment. We have re-examined the radiocarbon age of Toomba flow using newly sampled charcoal buried beneath the Toomba flow in combination with hydrogen pyrolysis pre-treatment and accelerated mass spectrometer (AMS) measurements. We determined a calibrated radiocarbon age of 20,815-19,726 cal BP (2r) for the material beneath the Toomba flow. Our radiocarbon age, therefore: (1) is older than previous radiocarbon ages for the Toomba flow, (2) provides the most precise age yet available for the Toomba flow, (3) is in agreement with the 40Ar/39Ar age, and (4) validates that hydrogen pyrolysis is a robust and effective pre-treatment method, for subtropical conditions where samples are susceptible to contamination by younger carbon. The Toomba flow erupted during the Last Glacial Maximum, but the preserved surface suggests that the rate of weathering and soil formation has been almost negligible in this region, despite being situated in a subtropical climate that experiences highly variable often intense rainfall. [ABSTRACT FROM AUTHOR]

The southwestern Pacific region consists of segmented and translated continental fragments of the Gondwanan margin. Tectonic reconstructions of this region are challenged by the fact that many fragmented continental blocks are submerged and/or concealed under younger sedimentary cover. The Queensland Plateau (offshore northeastern Australia) is one such submerged continental block. We present detrital zircon geochronological and morphological data, complemented by petrographic observations, from samples obtained from the only two drill cores that penetrated the Paleozoic metasedimentary strata of the Queensland Plateau (Ocean Drilling Program leg 133, sites 824 and 825). Results provide maximum age constraints of 319.4 ± 3.5 and 298.9 ± 2.5 Ma for the time of deposition, which in conjunction with evidence for deformation, indicate that the metasedimentary successions are most likely upper Carboniferous to lower Permian. A comparison of our results with a larger dataset of detrital zircon ages from the Tasmanides suggests that the Paleozoic successions of the Queensland Plateau formed in a backarc basin that was part of the northern continuation of the New England Orogen and/or the East Australian Rift System. However, unlike most of the New England Orogen, a distinctive component of the detrital zircon age spectra of the Mossman Orogen is also recognised, suggesting the existence of a late Paleozoic drainage system that crossed the northern Tasmanides en route from the North Australian Craton. A distinctive shift from abraded zircon grains to grains with well-preserved morphology at ca 305 Ma reflects a direct drainage of first-cycle sediments, most likely from an outboard arc and/or backarc magmatism. [ABSTRACT FROM AUTHOR]

The major stratigraphic units of the Fort Cooper Coal Measures (FCCM) have been reviewed, and an internal coal seam architecture using 500 wireline logs in the Bowen Basin, southeast Queensland has been developed. The subdivisions of the coal measures include the Burngrove Formation, Middle Main Seam and Fair Hill Formation in the northern Bowen Basin. To the south of the basin, the Middle Main Seam is interpreted as the stratigraphic equivalent of Black Alley Shale Formation. The Yarrabee Tuff forms the top boundary of the coal measures and is distributed basin-wide except over the southern Denison and southern Taroom troughs. Accessory tuffs beneath the Yarrabee Tuff aided seam level correlation. The geometries of coal seams have been analysed for each morphotectonic zone of the Bowen Basin using gravity data, which highlight high and low topographic sites. The Collinsville Shelf in northwest of the Bowen Basin comprises thick and merged Burngrove and Fair Hill formation coals that split towards northeast in the Nebo Synclinorium and southeast in Taroom Trough. Coal seams split into daughter seams from north to south and are named as first, second or third order, based on the number of splits that occurred. First- and second-order splitting occurs at the boundary of the Nebo Synclinorium and Collinsville Shelf, at the Narrows of Nebo Synclinorium and Comet Ridge. Further, third- and fourth-order splitting occurs at the boundary of the Comet Ridge and Taroom Trough. Splitting zones found at the junction of morphotectonic zones are related to a change in subsidence. In addition, the association of split seams with coarse grain-dominated interburden reflects increased accommodation in low-lying areas such as the Nebo Synclinorium and the troughs. Thick and coalesced coal seams are associated with shelves and ridges of the basin reflecting low accommodation sites. Hence, the variation in the coal seam architecture of FCCM responds to the subsidence associated with different morphotectonic zones of the basin. [ABSTRACT FROM AUTHOR]

The New England Orogen in eastern Australia is characterised by orogenic-scale curvatures (oroclines). The largest and most prominent curvature in this system is the Texas Orocline, but its subsurface geometry is still poorly constrained. A large component of the orocline is covered by post-oroclinal sedimentary rocks, which obscure deeper sections of the orocline and make it difficult to understand how the structure is connected to other segments of the New England Orogen. Here, we present geophysical data that elucidate the structure of the Texas Orocline below the sedimentary cover. Using 2D seismic, aeromagnetic TMI (total magnetic intensity) and Bouguer gravity datasets, in combination with outcrop and well data, we identified the depth to the New England ‘basement’ and significant faults intersecting it. We also traced the strongly contorted subsurface continuation of the Peel-Yarrol Fault System, which is characterised by local gravity and magnetic anomalies associated with isolated serpentinite outcrops. Constraints on the timing of oroclinal bending were obtained from the interpretation of seismic transects, which showed that early Permian sedimentary rocks of the Bowen Basin were deposited in a subtrough that deviates from the general north–south trend of the Bowen Basin. The subtrough is oriented approximately parallel to the western limb of the Texas Orocline, thus suggesting that the orocline formed during and/or after early Permian rifting. Our analysis indicates that initial bending occurred contemporaneously with the development of the early Permian rift basins, most likely in the backarc region of a retreating subduction zone. Subsequently, phases of strike-slip and contractional deformation have further tightened the pre-existing curvatures. [ABSTRACT FROM PUBLISHER]

The Middle Jurassic Walloon Subgroup is a prolific coal seam gas (CSG) resource in the Surat Basin, Queensland. Sedimentary framework models constrain stochastic reservoir models of the geological heterogeneity, but there is limited basin analysis information in the public domain. Here we present a regionally consistent stratigraphic framework model for the Walloon CSG play in the eastern Surat Basin. Lithostratigraphic correlation of open-file industry and government wireline logs supports the interpretation of six subunits in the eastern Surat Basin (oldest–youngest: Durabilla Formation; Taroom Coal Measures; Tangalooma Sandstone; and Juandah Coal Measures, informally divided into three members named the lower Juandah Coal Measures, Juandah sandstone and upper Juandah Coal Measures). Important findings are that subunits within the Walloon Subgroup do not correlate along the entire CSG play area; in many places, the overlying Springbok Sandstone (Upper Jurassic) has incised to the lower Juandah Coal Measures level, removing the upper coal seam groups. The Walloon Subgroup thins to the south through a combination of depositional thinning and truncation. Lithofacies analysis and isopach maps support deposition in a southerly prograding fluvial system or clastic wedge. This stratigraphic and depositional interpretation informs models for hydrogeological studies of the Walloon Subgroup and underpins a regional assessment of controls on microbial methane distribution. [ABSTRACT FROM AUTHOR]