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The Permian Period was a critical time interval during which various blocks of the Qinghai-Tibetan Plateau have experienced profound and complex paleogeographical changes. The supercontinent Pangea was formed to its maximum during this interval, hampering a global east-to-west trending equatorial warm ocean current. Meanwhile, a semi-closed Tethys Ocean warm pool formed an eastward-opening oceanic embayment of Pangea, and became an engine fostering the evolutions of organisms and environmental changes during the Paleozoic-Mesozoic transition. Stratigraphy and preserved fossil groups have proved extremely useful in understanding such changes and the evolutionary histories of the Qinghai-Tibetan Plateau. Widely distributed Permian deposits and fossils from various blocks of the Qinghai-Tibetan Plateau exhibited varied characteristics, reflecting these blocks’ different paleolatitude settings and drifting histories. The Himalaya Tethys Zone south to the Yarlung Zangbo suture zone, located in the northern Gondwanan margin, yields fossil assemblages characterized by cold-water organisms throughout the Permian, and was affliated to those of the Gondwanaland. Most of the exotic limestone blocks within the Yarlung Zangbo suture zone are Guadalupian (Middle Permian) to Early Triassic in age. These exotic limestone blocks bear fossil assemblages that have transitional affinities between the warm Tethys and cold Gondwanan regions, suggesting that they most probably represent seamount deposits in the Neo-Tethys Ocean. During the Asselian to Sakmarian (Cisuralian, also Early Permian), the Cimmerian microcontinents in the northern part of Gondwana preserved glacio-marine deposits of Asselian to Sakmarian, and contained typical Gondwana-type cold-water faunas. By the middle Cisuralian (∼290–280 Ma), the Cimmerian microcontinents rifted off from the Gondwanaland, and drifted northward allometrically due to the active magmatism of the Panjal Traps in the northern margin of the Indian Plate. Two slices of microcontinents are discerned as a result of such allometic drifting. The northern Cimmerian microcontinent slice, consisting of South Qiangtang, Baoshan, and Sibuma blocks, drifted relatively quickly, and preserved widespread carbonate deposits and warm-water faunas since Artinskian. By contrast, the southern Cimmerian microcontinent slice, consisting of Lhasa, Tengchong, and Irrawaddy blocks, drifted relatively slowly, and were characterized by widespread carbonate deposits containing warm-water faunas of late Kungurian to Lopingian (Late Permian). As such, these blocks rifted off from the northern Gondwanan margin since at least the Kungurian. Thus, it can be inferred that these blocks were incorperated into the low latitude, warm-water regions later than the northern Cimmerian slice. Such discrepancies in depositional sequences and paleobiogeography imply that the rifting of Cimmerian microcontinents resulted in the formation of both Meso-Tethys and Neo-Tethys oceans during the Cisuralian. By contrast, the North Qiangtang block, because of its further northern paleogeographical position, contains warm-water faunas throughout the whole Permian Period that are affiliated well with the faunas from the South China, Simao, and Indochina blocks. Together, these blocks belonged to the members of the northern Paleo-Tethys Ocean. Thus, an archipelagic paleogeographical framework divided by Paleo-, Meso-, and Neo-Tethys oceans was formed, fostering a global biodiversity centre within the Tethys warm pool. Since most of the allochthonous blocks assembling the Qinghai-Tibetan Plateau were situated in the middle to high latitude regions during the Permian, they preserved most sensitive paleoclimate records of the Late Paleozoic Ice Age (LPIA), the Artinskian global warming event, and the rapid warming event at the end-Permian. Therefore, sedimentological and paleontological records of these blocks are the unique window through which we can understand global evolutions of tectonic movement and paleoclimate, and their impacts on spatiotemporal distributions of comtemporaneous biotas.

The Lopingian is one of the fastest rising periods of seawater strontium isotopic ratios (87Sr/86Sr) in earth history, and its mechanisms and increasing rates of the 87Sr/86Sr evolution were still disputed widely. These disputations among researchers were caused mainly by timeframe selection (sections’ thickness or data of radiometric ages), and different stratigraphic boundaries and un-upmost dated ages. This paper examined published 87Sr/86Sr data of the Lopingian, and projected them on timescales based on evolutionary and age constrained conodonts fossils. 87Sr/86Sr evolution vs fossil constraining timescales was re-established in this period. This research suggests: (1) 87Sr/86Sr excursion projects on fossil zones can truly support 87Sr/86Sr evolutionary pattern in the period; (2) 87Sr/86Sr evolution provides a new approach for stratigraphic research of marine carbonate sections in lieu of biostratigraphic data; (3) 87Sr/86Sr stratigraphy works on marine carbonate sections of different sedimentation rates even between different basins; (4) the 87Sr/86Sr data and its shift was dependent on samples materials and chemical treatment methods; (5) the increasing rate of marine water 87Sr/86Sr in the Late Permian is suggested as 5.4×10−5/Ma or slightly lower; (6) sedimentation age and its 87Sr/86Sr of the Lopingian marine carbonate suggested as: DPRO=259-(RS−0.70695)/5.4×10−5±1 Ma.

The tectonic setting of South China during the late Paleozoic is essential to understanding the geodynamics off the eastern margin of Pangea supercontinent due to its unique paleo‐position at the confluence of the Paleo‐Tethys and Panthalassic oceans. Limited late Paleozoic magmatic and matemorphic records in South China have hampered resolution of this tectonic setting. Here, we present integrated biostratigraphic, geochronological, and isotope geochemical data on the late Carboniferous siliciclastic rocks from southeast South China in order to decipher the tectonic evolution of the South China Block. The sandstones were predominantly sourced from the Wuyi Terrane via short‐distance transportation. Rapid exhumation of ca. 318 Ma plutonic rocks in the source region, evolution of source of magmatism, and continuous crustal thinning demonstrate that southeast South China underwent episodic lithospheric delamination triggered by thermal perturbation as a result of subduction of the paleo‐Pacific plate beneath the South China Block in the late Paleozoic. The South China Block, composed of the Yangtze and Cathaysia blocks, lay off the eastern edge of Pangea supercontinent during the late Paleozoic, drifting in isolation near the paleoequator until eventually amalgamated with the North China Block in the Permian‐Triassic. Widespread carbonate platform sedimentation and the absence of significant contemporaneous magmatic, structural and metamorphic records are collectively interpreted to indicate a stable passive continent margin setting. Recently, abundant late Paleozoic detrital zircons have been reported from Permian‐Triassic siliciclastic rocks in southeast South China. Here we carried out an integrated biostratigraphic, detrital zircon geochronological and Hf isotope geochemical study on a late Carboniferous succession in South China. Our fusulinid biostratigraphy and ages of youngest detrital zircons suggest rapid exhumation of plutonic rocks of ca. 318.5 ± 6.8 Ma. Besides, the Cathaysia Block underwent a continuous thinning and two distinct tectono‐thermal events at 370 and 335 Ma. Hf isotopic data suggests a trend of lesser contribution of melts from younger crust for middle‐late Paleozoic magmatisms. We propose that the southeastern South China underwent episodic lithospheric delamination triggered by thermal perturbation as a result of subduction of the paleo‐Pacific plate beneath the South China Block in the late Paleozoic. Granitoid rocks of ca. 318.5 Ma in source region were rapidly exposed in the late CarboniferousCathaysia Block underwent a continuous thinning with two distinct tectono‐thermal events at 370 and 335 Ma during the late PaleozoicThe southeastern South China underwent delamination triggered by subduction of the paleo‐Pacific plate during the late Paleozoic Granitoid rocks of ca. 318.5 Ma in source region were rapidly exposed in the late Carboniferous Cathaysia Block underwent a continuous thinning with two distinct tectono‐thermal events at 370 and 335 Ma during the late Paleozoic The southeastern South China underwent delamination triggered by subduction of the paleo‐Pacific plate during the late Paleozoic

The Global Stratotype Section and Point (GSSP) for the Permian-Triassic boundary was placed in Bed 27 of Meishan section D where the conodont species Hindeodus parvusfirst occurs. Bed 27 was usually considered comprising continuously-deposited, homogeneous silty limestone, with no depositional hiatus near the boundary. Detailed study on the boundary sequence revealed that a typical firmground characterized by Glossifungites ichnofacies developed about 2 cm below the Permian-Triassic boundary in Bed 27. Fossil content and lithology show apparent differences across the firmground crust. The abundance of the Permian bioclasts decreases significantly across the firmground, and is accompanied by a shift of dominating carbonate precipitation from calcite to dolomite. The firmground marked a rapid transgression at the very end of the Late Permian and significant shifts of sedimentary environment and paleoclimate. This transgressive submerging surface is also observed at the Huangzhishan section of the shallow-water carbonate platform facies in Zhejiang Province, the Jiangya section of the lower-slope to basinal-margin facies in Hunan Province, the Pingdingshan section of the basinal facies in Anhui Province of South China, as well as the Selong section in Tibet of the northern peri-Gondwana. The transgressive submerging surface marks the onset of a rapid global transgression at the latest Permian.