Records of abnormal gymnosperm pollen morphotypes from coeval localities in Russia and NW China provide independent and unique evidence of deteriorating atmospheric conditions at the close of the Permian. Although at similar palaeolatitude, the Vologda region of European Russia and the Junggar Basin of Xinjiang Province, China, were thousands of kilometres apart and on different tectonic plates. The co-occurrence of the megaspore Otynisporites eotriassicus Fuglewicz 1977 , and its restricted distribution elsewhere in marine sections with either Late Permian ammonoids or the basal Triassic conodont marker Hindeodus parvus , confirms the age range, and correlation of the Russian and NW Chinese sections. In three Chinese sections, rapid changes in carbon isotopic (δ 13 C org ) composition of between 4 and 10‰ occur over the intervals showing abnormal pollen. These patterns reflect bioclastic facies contributions responding to local environmental changes. They are nevertheless coincident with global perturbations in the atmosphere, caused by extensive volcanic activity around the Permian–Triassic boundary.

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A unique marine Permian–Triassic boundary section containing rich oil source rocks has been continuously cored in a petroleum borehole from the Perth Basin of Western Australia. Such sequences, which provide a biostratigraphic and environmental record at the time of the largest extinction event of the past 500 million years, are globally rare, and this is the first to be documented in Australia. Throughout geological history there have been periods of global marine anoxia that commonly resulted in the widespread deposition of petroleum source rocks, most notably in the mid‐Cretaceous and Late Jurassic. An apparent paradox is that, previously, source rocks have not been recognised in association with the Permian–Triassic boundary, despite widespread marine anoxia at this time. The Perth Basin source rocks contain abundant and unusual biomarkers, apparently related to the highly specialised and limited biota that flourished in the aftermath of the end‐Permian extinction event. Local conditions may have favoured source‐rock development, either due to higher productivity resulting from coastal upwelling or through enhanced preservation under strongly anoxic conditions.

Australia during the Late Carboniferous formed part of the Gondwana supercontinent and was close to the South Pole. Resulting continental glacigene deposits and cold water marine sequences in the Southern New England Orogen cannot be correlated biostratigraphically with Late Carboniferous successions in the northern hemisphere because they contain a low diversity biota endemic to Gondwana. Magnetostratigraphic correlation via the Permian-Carboniferous reversed magnetic superchron is presently uncertain. Sensitive high-resolution ion microprobe (SHRIMP) zircon dating of volcanics horizons in the sedimentary sequence of the Southern New England Orogen is now establishing relationships between the Gondwanan faunas and warm-climate European equivalents. In Continental sediments, correlation of the major Gondwanan glaciation of Late Carboniferous Australia is revised from Stephanian to early Namurian-Westphalian in age, a timing that matches that of the Hoyada Verde glaciation in Argentina. A major hiatus of > 15 Ma between Carboniferous rocks of the Southern New England Orogen and Permian rocks of the Sydney Basin of eastern Australia probably reflects the first deformational movements within the accretionary prism of the orogen. Nothorhacopteris , traditionally a Late Carboniferous indicator in Australia, now ranges from late Viséan to Westphalian, and an ‘enriched’ assemblage, previously correlated with the top of the Nothorhacopteris flora, is confined to the late Viséan to early Namurian. Palynofloras assigned to the Spelaeotriletes ybertii/Diatomozonotriletes birkheadensis Zones (Namurian-early Westphalian), are now confined to the Namurian, and a mid to late Westphalian age is indicated for a more diverse palynoflora identified as uppermost D. birkheadensis Zone (? = Asperispora reticulatispinosus Zone). In the cold climate marine sequence, the Levipustula levis brachiopod Zone appears to be confined to the early Namurian, and so partly corresponds in age to the continental glaciation.

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