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Anomalous mercury (Hg) contents recorded near the Permian‐Triassic boundary (PTB) are often linked to Siberian Traps Large Igneous Province (STLIP) volcanism and the Permian‐Triassic boundary mass extinction (PTBME). However, mounting evidence indicates that the relation between STLIP volcanism and Hg “anomalies” is not straightforward. This study focuses on the timing and provenance of volcanic fluxes around the PTBME in South China. We constrain carbon isotope (δ13C) and Hg concentration and isotope records by utilizing high‐precision U‐Pb zircon ages from two expanded deep‐water marine sections spanning the Late Permian to Early Triassic in the Nanpanjiang Basin. Results reveal two episodes of Hg enrichment. The oldest episode predates the onset of a large negative δ13C excursion, which is documented to be older than 252.07 ± 0.130 Ma. The second episode occurred between 251.822 ± 0.060 and 251.589 ± 0.062 Ma, coinciding with the nadir of the δ13C excursion. Volcanic ash geochemistry and Hg isotope compositions suggest that mercury was mainly sourced from subduction‐related volcanic arc magmatism in the Tethys region, which peaked between 251.668 ± 0.079 and 251.589 ± 0.052 Ma. These results are compatible with suggestions that regional arc volcanism contributed to the causes of the PTBME in South China and provide evidence that Hg anomalies close to the PTB are not a reliable stratigraphic marker for the PTB extinction event. This study demonstrates that relations between volcanism, environmental perturbations and mass extinction during the Permian‐Triassic transition are better resolved with the aid of high‐precision U‐Pb zircon ages. Plain Language Summary Unusually high mercury contents in sedimentary rock sequences and the mass extinction of organisms during the transition from the Permian‐Triassic Period are often linked to Siberian Traps volcanism. However, results from several studies indicate that the relationship between this massive volcanism and mercury peaks in Permian‐ to Triassic‐aged rocks in the South China region is complex. This study combines the geochemical and isotopic records of carbon and mercury from Late Permian to Early Triassic sedimentary rocks, with absolute ages determined from interlayered volcanic ashes, to investigate the presence, timing, and source of volcanic inputs to these rock successions in South China. Results show higher mercury concentrations in two intervals, one before and after the Permian‐Triassic boundary (PTB). Absolute age results indicate that the mercury peak closest to the PTB occurred around 300,000 years after the mass extinction. We attribute the mercury peaks to more local volcanic activity than the far away Siberian Traps and suggest that this regional‐scale volcanic activity began shortly before 252 million years ago (Ma) and peaked around 251.6 Ma. Key Points Mercury concentrations show elevated volcanic fluxes to South China before and after the Permian‐Triassic boundary (PTB) The recorded mercury anomalies are attributed primarily to regional subduction‐related arc volcanism, not the Siberian Traps Mercury anomalies close to the PTB are not a reliable stratigraphic marker for the mass extinction event

Late Early Permian-lowermost Triassic carbonate, siliceous (spiculites) and clastic marine sediments in the Marmierfjellet area (Isfjorden, central Spitsbergen) contain a relatively diverse and abundant trace fossil assemblage providing important information about the depositional processes. The Vøringen Member (Late Artinskian-Kungurian) of the Kapp Starostin Formation (Late Artinskian-? Changhsingian) contains trace fossils (Nereites, Phycosiphon, Zoophycos and Arenicolites-common in tempestites) typical of the proximal-archetypal Cruziana ichnofacies, which indicates lower shoreface. Nereites, Phycosiphon and Zoophycos, accompanied by other rare trace fossils, characterize the Svenskegga and Hovtinden members of the Kapp Starostin Formation. They are interpreted as the distal Cruziana ichnofacies, possibly transitional to the Zoophycos ichnofacies typical of the lower offshore zone. However, the sporadic occurrences of Arenicolites and Macaronichnus can point to episodic shallowing to upper offshore-lower shoreface. The lowest part of the Triassic Vikinghøgda Formation (Induan-Olenekian) contains a very low-diverse ichnoassemblage composed of a few simple and branched forms ascribed to the impoverished Cruziana ichnofacies (lower to upper offshore environment), which is attributed to the early recovery stage after the Permian-Triassic extinction. The trace fossils and loss of primary sedimentary structures caused by intense bioturbation throughout most of the section point to generally oxygenated pore waters on the sea floor. However, some horizons, especially laminated black shales, display reduced or no bioturbational activity. These horizons also show high V/(V+Ni) ratios, which indicate oxygen-depleted sediments with periods of anoxic conditions. A remarkable black shale unit deposited under anoxic and sulphidic conditions occurs at the Permian-Triassic transition.

Lithium (Li) isotope analyses of sedimentary rocks from the Meishan section in South China reveal extremely light seawater Li isotopic signatures at the Permian–Triassic boundary (PTB), which coincide with the most severe mass extinction in the history of animal life. Using a dynamic seawater lithium box model, we show that the light seawater Li isotopic signatures can be best explained by a significant influx of riverine [Li] with light δ⁷Li to the ocean realm. The seawater Li isotope excursion started ≥300 Ky before and persisted up to the main extinction event, which is consistent with the eruption time of the Siberian Traps. The eruption of the Siberian Traps exposed an enormous amount of fresh basalt and triggered CO₂ release, rapid global warming, and acid rains, which in turn led to a rapid enhancement of continental weathering. The enhanced continental weathering delivered excessive nutrients to the oceans that could lead to marine eutrophication, anoxia, acidification, and ecological perturbation, ultimately resulting in the end-Permian mass extinction.

Palynostratigraphy across the Permian—Triassic of the Salt Range and Surghar Range area remains poorly known because of the predominance of unsuitable facies and preservation (Nammal, Chhidru, Chitta-Landu and Narmia). Dolomite and limestone in the basal Mianwali Formation prevented the establishment of a palynostratigraphic scheme for the basal Early Triassic (Hermann et al. 2012). Based on the study of a new Permian—Triassic section in the Amb valley where siltstone layers are intercalated in the basal Mianwali Formation (Kathwai Member), we describe a new record of palynological assemblages from the uppermost Permian Chhidru Formation and the lowermost part of the Early Triassic Mianwali Formation. The latest Permian Chhidru 2 sporomorph association occurs in the uppermost part of the Chhidru Formation, the so-called ‘white sandstone unit’. It is marked by the dominance of bisaccate pollen grains (mainly Protohaploxypinus spp.) and cavate trilete spores (mainly Kraeuselisporites spp.). Here, the previously described lowermost Triassic palynozone PTr 1 is subdivided into two subzones. PTr 1a assemblages are described from the Griesbachian Kathwai Member. They are characterized by continued high bisaccate pollen grain abundances and the presence of the lycopod genera Lundbladispora spp. and Densoisporites spp. In these assemblages, typical ‘Permian taxa’ and typical ‘Triassic taxa’ are mixed. The composition of the middle Dienerian PTr 1b assemblages corresponds to the previously described PTr 1 assemblage from Nammal and Chitta-Landu. Lundbladispora spp. and Densoisporites spp. account for ca. 80% of the total assemblage in PTr 1b. Although the Griesbachian assemblages record a decrease in diversity, the middle Dienerian assemblages represent the poorest assemblages of the studied Permian—Triassic interval. Reduviasporonites occurs only sporadically throughout the Amb succession.

The upper carbonate member of the Kaibab Formation in northern Arizona (USA) was subaerially exposed during the end Permian and contains fractured and zoned chert rubble lag deposits typical of karst topography. The karst chert rubble has secondary (authigenic) silica precipitates suitable for estimating continental weathering temperatures during the end Permian karst event. New oxygen and hydrogen isotope ratios of secondary silica precipitates in the residual rubble breccia: (1) yield continental palaeotemperature estimates between 17 and 22 °C; and, (2) indicate that meteoric water played a role in the crystallization history of the secondary silica. The continental palaeotemperatures presented herein are broadly consistent with a global mean temperature estimate of 18.2 °C for the latest Permian derived from published climate system models. Few data sets are presently available that allow even approximate quantitative estimates of regional continental palaeotemperatures. These data provide a basis for better understanding the end Permian palaeoclimate at a seasonally-tropical latitude along the western shoreline of Pangaea.

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.

There is a long-standing controversy of what triggered the extinction at the Permian-Triassic boundary, the most severe mass extinction in the geologic record, including flood basaltic volcanism and/or bolide impact hypothesis. In order to clarify various pieces of evidence for the mass extinction event at the Permian-Triassic boundary, some researchers from some laboratories throughout the world have made a comprehensive study on a group of samples from the Meishan area of China. Some fresh core samples from the Permian-Triassic boundary in the Meishan area were analyzed in this study. The results showed that there is no Ir anomaly, Moreover, the PGEs patterns of those samples show obvious differentiation characteristics, that is different from the case encountered in meteorites. So no evidence supports the hypothesis of extraterrestrial impact. In contrast, the PGEs patterns are similar to those of Siberian and Emeishan basalts, which indicates that those PGEs are derived mainly from the basalts, lending a support to the correlation between mass extinction at the Permian-Triassic boundary and flood basaltic volcanism. This study has also confirmed the results for samples from section C prior to the analysis of the samples.

Studies of the end-Permian mass extinction have suggested a variety of patterns from a single catastrophic event to multiple phases. But most of these analyses have been based on fossil distributions from single localities. Although single sections may simplify the interpretation of species diversity, they are susceptible to bias from stratigraphic incompleteness and facies control of preservation. Here we use a data set of 1450 species from 18 fossiliferous sections in different paleoenvironmental settings across South China and the northern peri-Gondwanan region, and integrate it with high-precision geochronologic data to evaluate the rapidity of the largest Phanerozoic mass extinction. To reduce the Signor-Lipps effect, we applied constrained optimization (CONOP) to search for an optimal sequence of first and last occurrence datums for all species and generate a composite biodiversity pattern based on multiple sections. This analysis indicates that an abrupt extinction of 62% of species took place within 200 Kyr. The onset of the sudden extinction is around 252.3 Ma, just below Bed 25 at the Meishan section. Taxon turnover and diversification rates suggest a deterioration of the living conditions nearly 1.2 Myr before the sudden extinction. The magnitude of the extinction was such that there was no immediate biotic recovery. Prior suggestions of highly variable, multi-phased extinction patterns reflect the impact of the Signor-Lipps effect and facies-dependent occurrences, and are not supported following appropriate statistical treatment of this larger data set.

Permian–Triassic boundary (PTB) volcanic ash beds are widely distributed in South China and were proposed to have a connection with the PTB mass extinction and the assemblage of Pangea. However, their source and tectonic affinity have been highly debated. We present zircon U–Pb ages, trace-element and Hf isotopic data on three new-found PTB volcanic ash beds in the western Hubei area, South China. Laser ablation inductively coupled plasma mass spectrometry U–Pb dating of zircons yields ages of 252.2 ± 3.6 Ma, 251.6 ± 4.9 Ma and 250.4 ± 2.4 Ma for these three volcanic ash beds. Zircons of age c . 240–270 Ma zircons have negative ε Hf ( t ) values (–18.17 to –3.91) and Mesoproterozoic–Palaeoproterozoic two-stage Hf model ages ( T Hf2 ) (1.33–2.23 Ga). Integrated with other PTB ash beds in South China, zircon trace-element signatures and Hf isotopes indicate that they were likely sourced from intermediate to felsic volcanic centres along the Simao–Indochina convergent continental margin. The Qinling convergent continental margin might be another possible source but needs further investigation. Our data support the model that strong convergent margin volcanism took place around South China during late Permian – Early Triassic time, especially in the Simao–Indochina active continental margin and possibly the Qinling active continental margin. These volcanisms overlap temporally with the PTB biocrisis triggered by the Siberian Large Igneous Province. In addition, our data argue that the South China Craton and the Simao–Indochina block had not been amalgamated with the main body of Pangea by late Permian – Early Triassic time.

A complete marine uppermost Permian to Lower Triassic succession is well exposed at the Daxiakou section of the Three Gorges area, western Hubei Province, South China. A total of 12 conodont zones are recognized from the uppermost Changhsingian (upper Permian) to Olenekian (Lower Triassic). Of these, the Clarkina yini, Clarkina meishanensis, and Clarkina taylorae Zones characterize the uppermost Changhsingian, whereas the Hindeodus parvus, Isarcicella staeschei, Isarcicella isarcica, Neoclarkina krystyni, Neoclarkina discreta, Sweetospathodus kummeli, and Neospathodus dieneri Zones define the Induan. Early Olenekian conodonts are assignable to the Novispathodus waageni and Nv. pingdingshanensis Zones. Conodont zones across the Permian-Triassic boundary (PTB) beds at Daxiakou correlate well with those established from the Meishan section, the Global Stratotype Section and Point (GSSP) for the PTB. The PTB is placed at the base of Bed 11c at Daxiakou. The Ns. dieneri M1, Ns. dieneri M2, and Ns. dieneri M3 subzones are distinguished from the Ns. dieneri Zone. Both Nv. waageni eowaageni and Nv. waageni waageni subzones are also recognized within the Nv. waageni Zone. The first occurrence of Nv. waageni eowaageni is an ideal marker defining the Induan–Olenekian boundary (IOB), which is calibrated to the base of Bed 86a at Daxiakou and is clearly beneath the ammonoid Flemingites-Euflemingites Zone.