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Mafic igneous units within sedimentary basins can be widespread and severely attenuate seismic reflection data. Attenuation obscures imaging of sub-igneous sedimentary units, impeding exploration in prospective and frontier basins. This study compared historical 2D seismic surveys and found two seismic acquisition parameters that have the greatest influence when imaging beneath mafic igneous rocks in offshore and onshore basins from Australia's Northwest Shelf. These parameters were found by using a 3D model developed with integrated 2D seismic and well data in the Browse, North Carnarvon, Onshore and Offshore Canning basins. Simultaneously comparing the 2D seismic lines in 3D space revealed that the surveys with the longest, streamer length and the most receivers are the most effective at imaging beneath igneous units. Additionally, we identified potential depocenters obscured by igneous horizons from a regional basement map. These depocenters correlate with older basins that are infilled by pre-rift, Paleozoic sediment and capped by mafic igneous rocks formed during late Permian-Mesozoic rifting events. Much of the Northwest Shelf maintains a frontier status, but exploration outcomes can be improved. Therefore, maximising streamer length and number of receivers to future seismic surveys can result in more effective exploration opportunities in basins with known igneous occurrences. [ABSTRACT FROM AUTHOR]

Background. The megalichthyids are one of several clades of extinct tetrapodomorph fish that lived throughout the Devonian Permian periods. They are advanced "osteolepidid-grade" fishes that lived in freshwater swamp and lake environments, with some taxa growing to very large sizes. They bear cosmine-covered bones and a large premaxillary tusk that lies lingually to a row of small teeth. Diagnosis of the family remains controversial with various authors revising it several times in recent works. There are fewer than 10 genera known globally, and only one member definitively identified from Gondwana. Cladarosymblema narrienense Fox et al. 1995 was described from the Lower Carboniferous Raymond Formation in Queensland, Australia, on the basis of several well-preserved specimens. Despite this detailed work, several aspects of its anatomy remain undescribed. Methods. Two especially well-preserved 3D fossils of Cladarosymblema narrienense, including the holotype specimen, are scanned using synchrotron or micro-computed tomography (μCT), and 3D modelled using specialist segmentation and visualisation software. New anatomical detail, in particular internal anatomy, is revealed for the first time in this taxon. A novel phylogenetic matrix, adapted from other recent work on tetrapodomorphs, is used to clarify the interrelationships of the megalichthyids and confirm the phylogenetic position of C. narrienense. Results. Never before seen morphological details of the palate, hyoid arch, basibranchial skeleton, pectoral girdle and axial skeleton are revealed and described. Several additional features are confirmed or updated from the original description. Moreover, the first full, virtual cranial endocast of any tetrapodomorph fish is presented and described, giving insight into the early neural adaptations in this group. Phylogenetic analysis confirms the monophyly of the Megalichthyidae with seven genera included (Askerichthys, Cladarosymblema, Ectosteorhachis, Mahalalepis, Megalichthys, Palatinichthys, and Sen-goerichthys). The position of the megalichthyids as sister group to canowindrids, crownward of "osteolepidids" (e.g., Osteolepis and Gogonasus), but below "tristichopterids" such as Eusthenopteron is confirmed, but our findings suggest further work is required to resolve megalichthyid interrelationships. [ABSTRACT FROM AUTHOR]

Archaeologists often wonder how and when rock shelters formed, yet their origins and antiquity are almost never systematically investigated. Here we present a new method to determine how and when individual boulders and rock shelters came to lie in their present landscape settings. We do so through 3D laser (LiDAR) mapping, illustrating the method by example of the Borologa Aboriginal site complex in the Kimberley region of northwestern Australia. Through a combination of geomorphological study and high‐resolution 3D modelling, individual blocks of rock are refitted and repositioned t680their originating cliff‐line. Preliminary cosmogenic nuclide ages on exposed vertical cliff faces and associated detached boulders above the Borologa archaeological sites signal very slow detachment rates for the mass movements of large blocks down the Drysdale Valley slopes, suggesting relative landscape stability over hundreds of thousands of years (predating the arrival of people). These findings offer hitherto unknown details of the pace of regional landscape evolution and move us toward a better understanding of patterns of human occupation in a context of relatively stable rock outcrops both within the sites and across the region. [ABSTRACT FROM AUTHOR]

Archaeologists usually see, and understand, rock shelters as taphonomically active, but pre-existing, physical structures onto which people undertake a variety of actions including rock art. Our aim in this paper is not only to document the changes undergone by rock shelters but also to identify traces of anthropic actions that have intentionally led to these changes. Recent research in northern Australia provides empirical evidence that for thousands of years, Aboriginal peoples altered the physical shape of rock shelters by removing masses of rock to create alcoves, restructure internal spaces and create stone-worked furniture. Through archaeomorphological research, this paper presents evidence from Borologa in Australia's Kimberley region, where hard quartzite monoliths were shaped and engaged as architectural designs by Aboriginal people prior to painting many surfaces, making us rethink what have traditionally been distinguished as natural versus cultural dimensions of archaeological landscapes and rock art sites. [ABSTRACT FROM AUTHOR]

Electromagnetics (EM) has been used extensively for Volcanic Hosted Massive Sulphide (VHMS) exploration in Australia. Exploring under conductive cover introduces significant limitations when using EM to identify bedrock conductivity anomalies that may be associated with VHMS deposits. We present an alternative approach, whereby robust geological modelling of the Airborne Electromagnetic (AEM) data plays a major role in the exploration strategy in the Bryah and Yerrida Basins of central Western Australia. The AEM is not only used for the identification of bedrock conductors but also forms a critical dataset constraining a robust basin-wide geological model. This model is used to identify priority areas for follow up surface geophysics and geochemistry. A patchwork of AEM surveys, covering portions of the Bryah and Yerrida basins, has been acquired by various explorers and contractors during the last decade. Systems and system specifications vary greatly. Accordingly, accurate geological interpretation of a basin-scale area, flown using various systems, cannot be derived from either raw data or fast/approximate conductivity products provided by contractors. All datasets require reconciliation with a common workflow and robust modelling strategy. Historic AEM data acquired with different systems along the edges of the tenure have been reprocessed and inverted. The remaining central block awaits the contractor's arrival before the data is subject to the same workflow. The end result will be a seamless basin-wide 3D conductivity model (extending over 6500 km2), which will inform the geological interpretation and subsequent follow-up exploration efforts. The preliminary 3D models already allow clear identification and modelling of the pyritic shale horizons, enabling the anomalous geochemistry and strongly conductive nature of these units to be discounted in the targeting process [ABSTRACT FROM AUTHOR]