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LA–ICP–MS in situ U–Pb monazite geochronology and P–T pseudosections are combined to evaluate the timing and physical conditions of metamorphism in the SE Anmatjira Range in the Aileron Province, central Australia. All samples show age peaks at c. 1580–1555 Ma, with three of five samples showing additional discrete age peaks between c. 1700 and 1630 Ma. P–T phase diagrams calculated for garnet–sillimanite–cordierite–K‐feldspar–ilmenite–melt bearing metapelitic rocks have overlapping peak mineral assemblage stability fields at ~870–920 °C and ~6.5–7.2 kbar. P–T modelling of a fine‐grained spinel–cordierite–garnet–biotite reaction microstructure suggests retrograde P–T conditions evolved down pressure and temperature to ~3–5.5 kbar and ~610–850 °C. The combined geochronological and P–T results indicate the SE Anmatjira Range underwent high‐temperature, low‐pressure metamorphism at c. 1580–1555 Ma, and followed an apparently clockwise retrograde path. The high apparent thermal gradient necessary to produce the estimated P–T conditions does not appear to reflect decompression of high‐P assemblages, nor is there syn‐metamorphic magmatism or structural evidence for extension. Similar to previous workers, we suggest the high‐thermal gradient P–T conditions could have been achieved by heating, largely driven by high heat production from older granites in the region.

Extensive collections of Pennsylvanian marine gastropods from 20 marine units in the Appalachian Basin contain 227 recognizable taxa. Twenty-two new species and subspecies are recognized includingBellerophon(Bellerophon)laticallis, B.(B.)graphicus varicallis, B.(Pharkidonotus)breyeri, Knightites(Cymatospira)montfortianus discordis, K.(Retispira)fascireticulatus, Colpites lirata, Abylea formosa, A. paradoxus, A insolitus, Spiroscala decorata, Euconospira equisita, Neilsonia invisitata, Worthenia parvula, Gosseletina nodosa, Glyptotomaria(Dictyotomaria)concinna, G.(D.)facta, G.(D.)decora, Phymatopleura preclara, Callispira grossa, Ceraunocochlis?subulata, Streptacis?ingens, and S.?complanata.Correlation of marine stratigraphic units within the collection area are discussed. Zonation on the basis of pseudozygopleurid taxa, following that of Anderson et al. (1989), is presented as well as mention of characteristic taxa of the various series.

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Specimens of the gastropod genus Donaldina are numerous throughout marine units of the Pottsville, Allegheny, and Conemaugh Groups in the Appalachian Basin. Six species of Donaldina from thirteen marine units are described. New species proposed are Donaldina quadroliratus, from Pottsville and Allegheny units, and Donaldina superclivis, from Conemaugh units.

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The Neoproterozoic–Paleozoic Officer Basin, located in South Australia and Western Australia, remains a frontier basin for energy exploration, with significant uncertainty due to a paucity of data. As part of Geoscience Australia’s Exploring for the Future (EFTF) program, the objective of this study is to derive the petrophysical properties and to characterise potential reservoirs in the Neoproterozoic–Cambrian sedimentary succession in the Officer Basin through laboratory testing and well log interpretation using both conventional and neural network methods. Laboratory measurements of 41 legacy core samples provide the relationships between gas permeability, Klinkenberg corrected permeability, and nano-scale permeability, as well as grain density, effective and total porosity for various rock types. Conventional log interpretation generates the volume fraction of shale, effective and total porosity from gamma ray and lithology logs. A self-organising map (SOM) was used to cluster the well log data to generate petrophysical group/class index and probability profiles for different classes. Neural network technology was employed to approximate porosity and permeability from logs, conventional interpretation results and class index from SOM modelling. The Neoproterozoic−Cambrian successions have the potential to host both conventional and tight hydrocarbon reservoirs. Neoproterozoic successions are demonstrated to host mainly tight reservoirs with the range in average porosity and geometric mean permeability of 4.77–6.39% and 0.00087–0.01307 mD, respectively, in the different sequences. The range in average porosity and geometric mean permeability of the potential Cambrian conventional reservoirs is 14.54−26.38% and 0.341−103.68 mD, respectively. The Neoproterozoic shales have favourable sealing capacities. This work updates the knowledge of rock properties to further the evaluation of the resource potential of the Officer Basin.