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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]

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]

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]