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The Lung Cam expanded stratigraphic succession in Vietnam is correlated herein to the Meishan D section in China, the GSSP for the Permian–Triassic boundary. The first appearance datum of the conodontHindeodus parvusat Meishan defines the Permian–Triassic boundary, and using published graphic correlation, the Permian–Triassic boundary level has been projected into the Lung Cam section. Using time-series analysis of magnetic susceptibility (χ) data, it is determined thatH. parvusarrived at Lung Cam ∼18 kyr before the Permian–Triassic boundary. Data indicate that the Lung Cam section is expanded by ∼90 % relative to the GSSP section at Meishan. Given the expanded Lung Cam section, it is possible to resolve the timing of significant events during the Permian–Triassic transition with high precision. These events include major stepped extinctions, beginning at ∼135 kyr and ending at ∼110 kyr below the Permian–Triassic boundary, with a duration of ∼25 kyr, followed by deposition of Lung Cam ash Bed + 13, which is equivalent to Siberian Traps volcanism is graphically correlated to a precession Time-series model, placing onset of this major volcanic event at ~242 kyr before the PTB. The Meishan Beds 25 and 26, at ∼100 kyr before the Permian–Triassic boundary. In addition, the elemental geochemical, carbon and oxygen isotope stratigraphy, and magnetostratigraphy susceptibility datasets from Lung Cam allow good correlation to other Permian–Triassic boundary succession. These datasets are helpful when the conodont biostratigraphy is poorly known in sections with problems such as lithofacies variability, or is undefined, owing possibly to lithofacies exclusions, anoxia or for other reasons. The Lung Pu Permian–Triassic boundary section, ∼45 km from Lung Cam, is used to test these problems.

Conodonts are rare in the Permian carbonates of Indochina but abundant conodonts and ostracodes have been obtained from turbiditic limestones of the Permian E-Lert Formation along with radiolarians from overlying cherts, all deposited on the margins of the interplatform Nam Duk Basin. Conodonts are typically Tethyan and are very similar to faunas from Sicily and south China. They includeHindeodus gulloides,Pseudohindeodus oertlii,Mesogondolella siciliensisandSweetognathus subsymmetricuswhich indicate a probable late Kungurian – Roadian age range although a Wordian age cannot be excluded.M. siciliensis, which has a high blade and small cusp supposedly typical of warm-water conodonts, is found in deep (Albaillella asymmetrica,A. sinuata,Tormentum delicatumandLatentifistula patagilateratasuggest a latest Kungurian – earliest Roadian age, deposited at a palaeodepth ofc.500 m. Ostracodes consist of 16 genera and 23 species which belong toShivaella,Paraberounella,Carinaknightina,Paraparchites,Shemonaella,Bairdia,Cryptobairdia,Bairdiacypris?,Spinocypris,Pseudobythocypris,Baschkirina,Microcheilinella,Basslerella,PolycopeandCyathus, of whichShivaella elertensis sp. nov.Chitnarin is newly described. The ostracodes are a palaeoecologically mixed assemblage comprising external platform and deeper-water forms, suggesting that the limestone turbidites were deposited on the proximal part of the slope.Cyathus caperataandC. ellipticashow a palaeobiogeographic link to south China.

East Greenland is a classical area for the study of the Permian–Triassic transition and the succession is one of the most expanded in the world. New ammonoid data from the Wordie Creek Formation have allowed us to better reconstruct the history of the East Greenland basin from semi-isolated basins with an endemic fauna during latest Permian–earliest Triassic H. triviale–H. martini zones time to well-connected open marine shelf basins during the Early Triassic M. subdemissum, O. commune, W. decipiens and B. rosenkrantzi Zone times. The East Greenland zonation can be correlated with Boreal zonations in Arctic Canada, Svalbard and northeastern Asia. It allows precise relative dating and correlation of important events across the Permian–Triassic boundary. The new ammonoid data indicate that deposition was continuous across the Permian–Triassic boundary and developed as a marine mudstone–mudstone contact in basinal areas of Hold With Hope, northern and southern Jameson Land. Correlation of the ammonoid stratigraphy with the FAD of Hindeodus parvus, which defines the base of the Triassic in Global Stratotype Section and Point (GSSP) in Meishan, China, suggests that the Hypophiceras triviale Zone is to be referred to the uppermost Permian, whereas the H. martini Zone is lowermost Triassic. Accordingly, the end-Permian marine and terrestrial extinctions and associated isotope changes as well as the subsequent adaptive radiations in East Greenland took place in latest Permian time. New Boreal faunas and floras were well established and diversified in the Hypophiceras triviale Zone prior to the beginning of the Triassic, and the Permian–Triassic boundary, in its present definition, is no longer reflecting major changes in the Earth system. It would have been fortunate if a GSSP were defined in a protracted section at a point of major environmental perturbations, marked by isotope excursions, chemical anomalies and mass extinction, rather than in the strongly condensed section like Meishan at a point which post-dates all significant events.