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Inertinite, as an important and abundant maceral group in coal, is critical for the study of palaeowildfires and their roles in the Earth's ecosystems. Recently, there has been a significant amount of research on the relationship between palaeowildfire, palaeoclimate change and palaeovegetation evolution based on inertinite data. The reflectance of fusinite and semifusinite has been used to estimate the combustion temperature and type of palaeowildfires, and then to evaluate the combustion characteristics of different types of palaeowildfires. The relative abundance of inertinite can be used to estimate the atmospheric oxygen contents. The rapid development of artificial intelligence (AI) and online tools to search scientific databases has presented an opportunity for us to find, collect, arrange, and analyse data from the earliest to latest publications on inertinite. The data extraction tool Deep Shovel is used to collect and analyse global inertinite data from the Silurian to the Neogene. The software programs such as Gplates, ArcGIS pro and Tableau are then applied to model the relative abundance of inertinite over geological time, which can be correlated with other parameters such as atmospheric oxygen contents, plant evolution and palaeoclimate changes. The distribution of inertinite in coals varied over different geological periods, being typified by the "high inertinite content-high atmospheric oxygen level" period in the Permian and the "low inertinite content-low atmospheric oxygen level" period in the Cenozoic. This study has proposed a possible model of the positive and negative feedbacks between inertinite characteristics and palaeoenvironmental factors, and has revealed the exceptional role of inertinite in palaeoenvironmental studies. Future research on inertinite will be focused on the integrated study of organic petrology and organic geochemistry of inertinite, the big data-driven research on the temporal and spatial distribution of the global inertinite, the exploration of the functions of palaeowildfires in the Earth systems in different climatic backgrounds, and the study of modern wildfires to better predict the future frequency and intensity of wildfires due to climate changes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Based on detailed field surveys, numerous sections and drillcores as well as analyses of lithofacies and sedimentary facies, sedimentary differentiation in the Middle Permian Zunyi (northern Guizhou, South China) trough basin was studied in detail. Caused by activities of the Emeishan mantle plume, the regional extensional setting and the extinguishing of carbonate production factories were shown from Guizhou to Yunnan. Three types of sedimentary enironments were developed in the study area: platform, slope, and basin. In this work, we established a sedimentary model for the study area, identified 14 syndepositional faults, and created the detailed reconstruction of the trough basin via a sedimentological investigation. It is found that the paleogeographic evolution of the study area can be divided into six stages: (1) a pre-rifting stage, (2) rapid rifting and subsidence, (3) stable rifting and subsidence, (4) the second stage of rifting and subsidence, (5) silicification, and (6) regional uplift and denudation. The sedimentary features and paleogeographic evolution of the Maokou Formation in Zunyi show that the platform, slope, and basin sedimentary features coexisted. In addition, the extensional setting and extinguishing of carbonate production factories were important preconditions for the evolution of the platform region in the study area, and the activity of syndepositional faults also played an important role in the paleogeographic evolution of this area. [ABSTRACT FROM AUTHOR]

The palaeofloristic study of Gondwana sediments recovered from Religara area, South Karanpura Basin illustrates the macrofloral diversity in the area. Three distinct megafloral assemblages I, II, III are reported from freshly exposed coaly shale and carbonaceous shale layers of lower Barakar, upper Barakar and Raniganj formations of the basin. The assemblage comprises 72 species and thirteen genera of which 28 are newly reported species, which clearly exemplifies the macrofloral diversity over Permian Period in the studied area. The retrieved floral assemblages justified the existence of two interrelated ecosystems i.e., terrestrial and marshy. A gradual shifting of leaf morphology in reticulate leaves of order Glossopteridales illustrates biostratigraphic age as well as the shifting of climate during the deposition of sediments. The dominance of narrow mesh Glossopteris flora with the presence of typical Karharbari flora in the lowermost fossil horizon, illustrating the biostratigraphic age as late Artinskian (lower Barakar Formation). Likewise, the middle and upper floristic zones are dominated by Glossopteris of intermediate mesh form and broad mesh form suggesting biostratigraphic age as Kungurian (upper Barakar) and Wordian-Changhsingian (Raniganj) respectively. Deposition of in- situ Vertebraria depicts the autochthonous coal deposits and existence of some patches of palaeosol in the investigated location. The present investigation aims to infer the biostratigraphy, palaeoclimate, palaeoenvironment, palaeovegetational reconstruction of the basin during late Artinskian–Kungurian and Wordian- Changhsingian times. [ABSTRACT FROM AUTHOR]

Herbivory evolved independently in several tetrapod lineages during the Late Carboniferous and became more widespread throughout the Permian Period, eventually leading to the basic structure of modern terrestrial ecosystems. Here we report a new taxon of edaphosaurid synapsid based on two fossils recovered from the Moscovian-age cannel coal of Linton, Ohio, which we interpret as an omnivore–low-fibre herbivore. Melanedaphodon hovaneci gen. et sp. nov. provides the earliest record of an edaphosaurid to date and is one of the oldest known synapsids. Using high-resolution X-ray micro-computed tomography, we provide a comprehensive description of the new taxon that reveals similarities between Late Carboniferous and early Permian (Cisuralian) members of Edaphosauridae. The presence of large bulbous, cusped, marginal teeth alongside a moderately-developed palatal battery, distinguishes Melanedaphodon from all other known species of Edaphosauridae and suggests adaptations for processing tough plant material already appeared among the earliest synapsids. Furthermore, we propose that durophagy may have provided an early pathway to exploit plant resources in terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

A palynological analysis of borehole RB-1, Raniganj Coalfield, Damodar Basin, has been presented here. Based on the quantitative analysis of the spores and pollen grains of the productive samples, three palynoassemblages have been identified: Palynoassemblage-I demarcated at a depth between 335.00 and 284.00 m is distinguished by the dominance of nonstriate bisaccate pollen Scheuringipollenites and subdominance of striate bisaccate pollen Faunipollenites suggestive of an early Permian (Artinskian) age; Palynoassemblage-II identified at a depth between 278.00 and 32.00 m shows the prominence of striate bisaccate mainly Faunipollenites, Striatopodocarpites and subdominance of Scheuringipollenites signifies late early Permian (Kungurian) age, and the youngest Palynoassemblage-III marked at a depth between 30.00 and 03.00 m contains dominance of striate disaccates pollen, viz., Striatopodocarpites, Crescentipollenites, and monosaccate pollen Densipollenites spp. (D. invisus, D. densus, D. magnicorpus) corroborate with the latest Permian Raniganj (Lopingian) age. The rare occurrence of Densoisporites contactus and Lundbladispora warti in the assemblage, define the upper limit of the Raniganj Formation. The assemblages have been correlated with the Indian as well as other Gondwanian continents. The dominance of gymnosperms pollen glossopteridales, conifers, and cordaites, lesser quantitative spores of lycopsids, sphenopsids, filiciopsids algal elements indicate that the palaeoclimatic condition was warm and high humid, during the deposition of these sediments in the study area of the Raniganj Coalfield. Research Highlights: Palynological study has been carried out for the subsurface coal deposits from the borehole RB-1, drilled at Raniganj Coalfield to attempt to establish chronology of the sediments. The palynological investigation reveals three palynoassemblage zones and dated as early to latest Permian (Artinskian to Lopingian) age and this assemblage reveals the dominance of gymnosperms plant group such as Glossopteridales followed by conifers and cordaitales. The FADs (First appearance of Datum) of Densoisporites contactus, Lundbladispora warti and Lunatisporites pellucidus in the assemblage III indicate the end of Permian period. The overall palynological composition suggests that a warm to very hot with medium to low humidity climatic condition were prevailing in the study area. [ABSTRACT FROM AUTHOR]

Continental ecosystems of the middle Permian Period (273–259 million years ago) are poorly understood. In South Africa, the vertebrate fossil record is well documented for this time interval, but the plants and insects are virtually unknown, and are rare globally. This scarcity of data has hampered studies of the evolution and diversification of life, and has precluded detailed reconstructions and analyses of ecosystems of this critical period in Earth's history. Here we introduce a new locality in the southern Karoo Basin that is producing exceptionally well-preserved and abundant fossils of novel freshwater and terrestrial insects, arachnids, and plants. Within a robust regional geochronological, geological and biostratigraphic context, this Konservat- and Konzentrat-Lagerstätte offers a unique opportunity for the study and reconstruction of a southern Gondwanan deltaic ecosystem that thrived 266–268 million years ago, and will serve as a high-resolution ecological baseline towards a better understanding of Permian extinction events. A new middle Permian fossil locality featuring a large abundance of exceptionally preserved plants and insects is identified in the Karoo Basin of South Africa. [ABSTRACT FROM AUTHOR]

The Barreiras Formation records continental-to-shallow–water marine sequences deposited during the Paleogene–Neogene periods in the Brazilian continental margin. In northern Rio de Janeiro and southern Espírito Santo states, the Barreiras Formation preserve alluvial depositional system. The sediments were derived from a source located in the hinterland of the southeastern Brazilian continental margin, where rocks formed or reworked notably during the Gondwana supercontinent assembly are exposed. Detrital zircon U–Pb ages are mostly late Neoproterozoic, dominantly close to 608 Ma. Source rocks of this age occurred within the Ribeira and Araçuaí belts and were formed during their main magmatic activity. U–Pb zircon age distribution is similar to the southern and central Ribeira belt. Zircon fission-track ages occur in four main groups, between 429 and 358 Ma, 351 and 274 Ma, 270 and 171 Ma, and 167 and 127 Ma. Complex variation in the detrital zircon fission-track ages is related to the continental crust thermal evolution in the source areas. Older ages also occur between 534 and 433 Ma (Cambrian-to-Silurian periods) and are chrono-correlated to post-orogenic processes after the Gondwana supercontinent agglutination. Zircon fission-track ages between 429 and 274 Ma (Silurian to Permian periods) are related to the formation of the Pangea supercontinent, whereas the predominant zircon fission-track age group, between 270 and 171 Ma (Permian to Jurassic periods), is chrono-correlated to both orogeneses in the Gondwana supercontinent west margin and the Pangea supercontinent breakup. Zircon fission-track ages from 167 to 127 Ma are in the same period as the opening of the North and South Atlantic oceans. Data indicate that the thermal evolution of the source region either during the Gondwana supercontinent and South America Platform stages is complex. [ABSTRACT FROM AUTHOR]

The eastern Junggar Basin, controlled by continental extension (rift), was deposited by lacustrine dominated sediments during middle Permian Lucaogou period. An unusual porphyritic-like texture was observed in Lucaogou/Pingdiquan dark fine-grained organic-rich sediments in two sub-tectonic units in the basin. The "phenocrysts" are composed of two types of mineral assemblages. The first is a coarse euhedral calcite assemblage in the Jimusar Sag, and the second consists of dolomite, analcime, and pyrite in the Shishugou Sag. The lithological and mineralogical features indicate a hydrothermal origin for these phenocryst-like minerals. The chondrite-normalized rare earth element patterns show flat or positive Ce anomalies and negative Eu anomalies, which reflect a suboxic to anoxic, off-axis site from the center of the fault system, where the temperature of the hydrothermal fluid might be less than 250 °C. The high ratios of BaN/LaN at 1.6–65.5, strongly positive Sr anomalies at Sr/Sr* = 5.54–39.9, and relatively low 87Sr/86Sr isotopes at 0.705002–0.705776 in the coarse calcite suggest an origin of mixed sources of lake water, underlying biogenetic sediments, and deep magmatic water. However, the low 87Sr/ 86Sr ratios of 0.705321–0.705968 in the dolomite and δ34SV-CDT of 10.8‰–12.3‰ in the pyrite indicate that water–underlying-rock interaction and the abiotic thermochemical sulfate reduction of lake water or organic matter might have participated together resulting in the precipitation of the dolomite–analcime–pyrite assemblages in the Shishugou Sag. [ABSTRACT FROM AUTHOR]

Organogenic buildups named as carbonate mounds are widespread in Lower Permian deposits in the northern Timan–Pechora basin and are of great interest to the oil-and-gas industry as natural hydrocarbon reservoirs. Their distribution and textural features were controlled by seabed morphology, sea level changes, and specific paleoecology of the Early Permian period. In contrast to classic reefs, these buildups were not able to form large accumulative landforms that changed the hydrodynamics and paleogeography of sedimentary basins. The results of this study allowed us to divide the Lower Permian carbonate buildups into two types: (1) skeletal mounds formed primarily by algae and Palaeoaplysina communities; (2) microbial mounds composed of microbial assemblages. Identification of these mounds based on seismic data usually does not meet any difficulties. However, their texture, peculiarities of reservoir distribution, and variations of their properties are often unreflected in the characteristics of seismic waves due to limitations of the seismic survey resolution. The sedimentation modeling describes spatiotemporal relationships of the identified lithofacies characterized by different reservoir potential. Application of these results during the seismic interpretation increases significantly reliability of the forecast of carbonate reservoir properties. [ABSTRACT FROM AUTHOR]

The paleo-sedimentary environment can be restored qualitatively or semiqualitatively using elements or combinations of elements that are sensitive to the depositional environment. Through the analysis and testing of the main elements, trace elements and rare earth elements of twenty-one Lower—Middle Permian coal-bearing strata mudstone samples in Taikang Uplift, southern North China Basin, this study explored the FOUR-PALEO conditions (paleo-water depth, paleo-redox conditions, paleoclimate and paleo-provenance). The La and Co contents indicate that the water depth of the northern margin of the southern North China Basin became gradually shallower during the Lower—Middle Permian period. According to the U/Th, Uau, V/Cr, Ni/Co and V/Sc ratios, it is known that this section of the basin is in an oxidizing environment, and the oxidation is gradually enhanced from the Taiyuan Formation to the Lower Shihezi Formation. Paleoclimate from bivariate plot diagrams of C-value and Sr/Cu versus Ga/Rb shows that the Taikang Uplift was characterized by a warm and arid climate during the depositional period of Permian Taiyuan Formation and a warm and humid climate during the Lower Shihezi Formation and shows that the depositional period of Permian Shanxi Formation was in a transitional period of humid and arid. CIA, PIA, ICV, Th/U and K/Rb reflect the tectonic settings of the source area. From the Taiyuan Formation to the Lower Shihezi Formation, the CIA and PIA gradually increase, and the ICV gradually decreases, indicating enhanced chemical weathering and the transition from arid to humid in the source area, the arid and humid frequent change in the Taiyuan Formation, and a sudden climate change in the Shanxi Formation. Additionally, the provenance discriminant function, Zr/Sc-Th/Sr, REEs ratios, Th versus Hf-Co, Hf versus La/Th and ZREE vs. La/Yb indicate that the type of provenance is associated with magmatic differentiation. Moreover, discriminant diagrams, consisting of K2O/Na2O versus SiO2, La-Th-Sc, Th-Sc-Zr/10 and Th-Co-Zr/10, suggest that the mudstones of Lower-Middle Permian were deposited in active continental margin tectonic settings. [ABSTRACT FROM AUTHOR]

Sinkiang Hami Redstone Copper in China is a super-large volcanic hydrothermal deposit formed as a result of multi-stage secondary tectonic activity in the Hercynian period of tectonic movement. In this work, we have studied the effect of the geomechanical nature on the structure of faults stretched in different directions and have studied the age of Hercynian U-Pb detrital rock in trenches by SHRIMP zircon dating. Our studies have shown that there were strong tectonic plate movements 286-218 million years ago, and a main mineralization stage in the period 285-270 million years ago. Our results showed four developmental fault zones with different properties in the Redstone copper: the first stage is represented by nearly EW and NWW, extensional fault zones in the Upper Carboniferous period, with which formation of the ore structure is associated; the second stage is represented by a nearly SN fault zone formed at the boundary between the Upper Carboniferous and the Lower Permian periods, in which mineralization occurred; the third stage is represented by a NE and NEE fault zone in the Upper Permian period; and the fourth stage is represented by NE faults in the Lower Triassic period, which are mainly broken ore structures. Study of the tectonic stresses showed the presence of the following stresses: NNE tension, nearly EW tension, a pair of sinistral SN horizontal shears and a pair of NNE horizontal shears, a pair of dextral SN horizontal shears and EW tension. [ABSTRACT FROM AUTHOR]

Gondwana deposits are extensively found across the continents. Here we study the Middle Permian Barakar Formation from the marginal Gondwana Basin, eastern India, being deposited in a normal fault setting. Availability of extensive cores as well as geophysical log suites (gamma-resistivity-density from drilled wells) from the study area helped us achieving high resolution interpretation. Core study identifies fluvial sedimentary architectures, which were correlated with the geophysical logs and modeled field-wide to understand vertical and horizontal facies disposition. The facies analysis has been used to establish a sequence stratigraphic model of the cyclic Barakar deposition. Four major fining upward depositional sequences were identified, each sequence comprises of low accommodation system tract (LAST) at base and high accommodation system tract (HAST) at top. LAST is characterized by vertically stacked, multistory amalgamated channel sandstone dominated facies, while floodplain dominated facies characterizes HAST, reflecting a gradual shift from braided to meandering depositional system from bottom to top of each cycle. Study reveals depocenter to be in the western part, supported by eastward thinning of sediment packets, all being deposited in a half-graben setting. [ABSTRACT FROM AUTHOR]

Terrestrial floras underwent important changes during the Lopingian (Late Permian), Early Triassic, and Middle Triassic, i.e., before, during, and after the end-Permian mass extinction. An accurate account of these developments requires reliable correlation. Macrofossils of land plants can only provide a low-resolution biostratigraphy, while detailed zonation schemes based on palynomorphs are available for many regions. Their applicability is still limited due to several factors, such as (micro-)floral provincialism, a lack of suitable marker taxa commonly occurring at important boundaries, and in many cases a lack of independent age control. Nevertheless, these palynostratigraphic schemes are regularly used for dating and correlation of successions between different regions. To support such efforts, the biozonation schemes based on palynomorphs from the Lopingian up to and including the Middle Triassic from across the world are summarized and revised. Thus, a consistent correlation of palynozones with the currently recognized international stages is established. [ABSTRACT FROM AUTHOR]

Organic component in the Lower Permian salt sequence in the southern part of the Yakshinskoe deposit of the Upper Pechora potassium basin is represented by dispersed organic matter, liquid hydrocarbons in fluid inclusions in halite, as well as inclusions of bacterium, algae, spore and pollen of plants. Analysis of saturated and aromatic bitumen fractions from salts, halopelites, and clayey-silty interbeds revealed the presence of organic matter of type II and mixed type II-III. It is shown that the cover sequence and potassium bed from the southern part of the Yakshinskoe potassium-magnesium salt deposit contain autochthonous immature organic matter, whereas underlying rock salt and host rocks contain significant amount of immature allochthonous components. These migration hydrocarbons are likely immature condensates. [ABSTRACT FROM AUTHOR]

Detailed sedimentological and geochemical records across the Permian-Triassic boundary (PTB) in five offshore wells of the central Persian Gulf served to interpret the end-Permian sea-level change in this region. A decrease in sea level at the PTB was established by petrographical and geochemical study of the boundary. Thin sections showed that Upper Permian strata are composed of dolomite with minor anhydrite, changing into limestone in Lower Triassic sediments. Brine dilution toward the boundary supports sea-level fall in the Permian-Triassic transition, reflected by a decrease in anhydrite content and a shallowing-upward trend from lagoonal to peritidal facies. Isotopic changes at the boundary are in favor of sea-level fall. Changes in both carbon (from about 4 to -1‰) and oxygen (from 2 to -5‰) stable isotopes show negative excursions. The shift in carbon isotope values is a global phenomenon and is interpreted as resulting from carbonate sediment interaction with 12C-rich waters at the end-Permian sea-level fall. However, the oxygen isotope shift is attributed to the effect of meteoric waters with negative oxygen isotope values. The increase in strontium isotope ratios is also consistent with the high rate of terrestrial input at the boundary. The effect of meteoric conditions during diagenesis is evident from vuggy and moldic porosities below the PTB. The following transgression at the base of the Triassic is evident from the presence of reworked fossils and intraclasts resulting from deposition from agitated water. [ABSTRACT FROM AUTHOR]

Two anatomically preserved calamitean axes are reported for the first time from the Late Permian Wutonggou Formation in the southern Bogda Mountains, Xinjiang Uygur Autonomous Region, Northwest China. Based on the anatomical features, these axes are assigned to Arthropitys. A new species Arthropitys taoshuyuanensis sp. nov. is established. A. taoshuyuanensis sp. nov. possesses a large pith and comprises large pith cavity and a narrow perimedullary zone at the nodes and diaphragms at the internodes. Carinal canals are circular and surrounded by a single layer of metaxylem tracheids. Secondary xylem is divided into interfascicular rays and fascicular wedges. Interfascicular rays are initially four to five cells wide and taper abruptly centrifugally. Fascicular wedge consists of thick-walled tracheids and thin-walled fascicular ray cells. Radial tracheid walls have uniseriate or biseriate circular pits, or scalariform pits. The absence of growth rings in the Arthropitys specimens indicates that they probably lived in the wetland area under stable annual temperature and water sufficient conditions. [ABSTRACT FROM AUTHOR]

In the conjunction zone of the East European Platform and the Uralian foredeep, involved in structures of the Southern Urals (Bashkiria), sediments deposited at the shelf zone edge in the Late Carboniferous-Early Permian crop out. The Upper Carboniferous bioherm and Lower Permian deep marine-shelf boundary limestones, composing Voskresenka Mount near Tabynsk township, were studied. Results of the complex analysis of lithofacies, paleontological, structural, and also geological and geophysical data show that the Voskresenka carbonate massif, previously attributed to a single reef structure, represents the SW-dipping tectonic horst block, composed of Upper Carboniferous shelf-bioherm limestones, which is uplifted in a near break zone. As a result of tectonic processes, the edge of the late Carboniferous carbonate platform, overlain by Asselian deep-water sediments, was exhumed. The sedimentary succession shows that the paleogeographic setting at the margin of the East European Craton changed at the Carboniferous-Permian boundary during the formation of the Ural collisional orogen. [ABSTRACT FROM AUTHOR]

An Early Triassic stromatolitic deposit is documented in the Dienerian succession of the Lower Triassic Feixianguan Formation in the Xingyi area, Guizhou, southwest China. Five types of constructional microbial forms at various scales were observed. (1) Typical stratified columnar structures, up to 25 cm in height, with crinkled laminae. Dark-coloured laminae, 1 mm thick, are composed of upright filamentous tubes, average diameter 5 µm, showing a vertical growth fabric. (2) Prostrate filaments showing strong fluorescence, in sharp contrast to the micritic cement. (3) Coccoid-like spheroids and algal filaments are also common in stromatolitic laminae. These resemble present-day cyanobacteria, and thus may represent fossilized cyanobacteria. (4) Smaller bacilli resembling Pelodictyon are very common in the stromatolitic laminae. (5) Framboidal pyrite is also abundant and probably indicates biological involvement in stromatolite formation. Two major microbial functional groups, oxygenic phototrophs represented by lithified cyanobacteria and probable sulfate-reducing bacteria represented by framboidal pyrite, were present during stromatolite growth. Another possible microbial functional group, anoxygenic phototrophs represented by lithified remains resembling Pelodictyon clathratiforme, may be present in the Xingyi stromatolites, and were involved in stromatolite formation by capturing or adhering microcrystalline particles. All of these features demonstrate that the Early Triassic stromatolites are biogenic. The occurrence of the Xingyi stromatolites, corresponding to a second episode of microbial growth during the Early Triassic, reveals that post-extinction microbialites were widespread in the Dienerian. These Early Triassic stromatolites indicate that a microbial bloom took place in the aftermath of the Permian-Triassic mass extinction. [ABSTRACT FROM AUTHOR]

A-type rhyolites of contrasting compositions and eruption characters were revealed among two volcanic series of the Early Permian bimodal association in the Nomgon graben. Rhyolites of the lower volcanic series formed extrusions, lava domes, and tuff horizons. They had low FeO, Zr, Hf, Nb, Ta, Y, and REE concentrations and also a moderately depleted Nd isotope composition (ε( Т) = 6.7-7.1). Their formation was related to anatexis of the juvenile continental crust, triggered by the thermal effect of mafic magmas. Rhyolites of the upper volcanic series formed extensive lava flows and dikes. Their composition was characterized by high FeO, Zr, Hf, Nb, Ta, Y, and REE concentrations, and also depleted Nd isotope characteristics (ε( Т) = 7.7-9.0). These rhyolite melts formed under long-term crystallizational differentiation of basaltoids in the intracrustal magmatic chambers, with limited participation of crustal contamination. The source of magmas for the upper volcanic series was the sublithospheric mantle. [ABSTRACT FROM AUTHOR]

A tectonothermal study of the northeastern sector of the Cantabrian zone (Ponga-Cuera and Picos de Europa units) using the conodont color alteration index (CAI) and Kübler index (KI) methods shows a variation from diagenetic to anchizonal conditions. The latter are illustrated in geological maps and cross sections. The greater part of the studied area has CAI values lower than 2, caused by two long periods of burial separated by a compressive interval (corresponding to the Variscan deformation), in which thrusts were the dominant structures. Tectonic superimposition was balanced by intense and fast erosion and had little effect on the CAI values. In contrast, a high thermal gradient was produced in the southern outcrops that led to recognize the transition between diagenetic and anchizonal conditions through CAI values near the basal thrust of the Picos de Europa unit. The diagenesis/anchizone boundary appears a little further south through the determination of the Kübler index in phyllosilicate minerals (KI = 0.42). CAI isograds cut the Variscan structures as a consequence of a thermal episode that occurred near the Carboniferous-Permian boundary at the beginning of an extensional regime. The thermal source was located further south, in the adjacent Pisuerga-Carrión unit. Alterations in the CAI values, as well as dolomitization and ore deposits, locally resulted from Permian-Mesozoic hydrothermal activity. Microtextural analysis of the conodonts allowed us to relate several types of apatite overgrowth to diagenetic conditions and recrystallization to anchizonal ones, whereas dissolution was common during hydrothermalism. Alpine deformation hardly produced any changes in the previous thermal pattern, but was responsible of the northwards tilting of the structure and CAI isograds. [ABSTRACT FROM AUTHOR]

Bulk-rock major and trace elements and zircon U-Pb data are reported for Permian metamafic rocks from Guoganjianan, in the western part of Longmuco-Shuanghu-Lancang suture zone. These results offer new insights into mantle source characteristics and geodynamic setting of Permian ophiolitic fragments. U-Pb isotopic dating using SHRIMP II method reveals that the metamafic rocks were formed at 274.7±3.9 and 279.8±3.6 Ma. The metamafic rocks mostly show N-MORB-typed rare earth element patterns and are enrichment in large-ion lithophile elements, indicating that they are probably derived from partial melting of a depleted mantle in a back-arc basin. Our new data, together with recent studied results on Paleozoic ophiolitic fragments suggest the Paleo-Tethys Ocean in Central Qiangtang opened at Cambrian and widened between Ordovician and Devonian. Northward subduction started in the Late Devonian-Early Carboniferous and a back-arc basin developed during Permian. [ABSTRACT FROM AUTHOR]

The Regional Stratigraphic Scale (RSS) of the Permian deposits in northeastern Russia represents the only complete stratigraphic succession of Permian marine deposits distinguished in Russia, which serves as a standard at the correlation of Permian deposits of all regions of the eastern part of the Boreal Biogeographic Superrealm. However, a high level of faunistic endemism makes it extremely difficult to correlate directly stratons of the RSS with stages of the International Stratigraphic Scale (ISS) of the Permian deposits. The first U-Pb SIMS age datings of zircons from felsic tuffs of the Omchak Formation of the Ayan-Yuryakh Anticlinorium (the lower part of the Permian Khivachian Horizon of the RSS of northeastern Russia) allowed us to obtain the important reference level for the Upper Permian subdivision of the Permian RSS. The zircon age of 257.1 ± 3.0 Ma is in good agreement with the stratigraphic position of the studied sample, which makes it possible to correlate the surrounding deposits with the Wuchiapingian Stage of the Permian deposits in the International Stratigraphic Scale. [ABSTRACT FROM AUTHOR]

A detailed study of a relatively well-exposed fragment of the Barabash Formation in the southern part of the Voznesenka terrane is carried out to specify the geodynamic settings of the Permian volcanogenic and volcanogenic-sedimentary complexes in South Primorye. It is established that the basaltic flows juxtaposed in the studied sequence originated from sharply different sources. The geochemical characteristics indicate that the basalts from the sequence base were presumably derived by melting of oceanic lithospheric mantle or asthenosphere, while the source of the overlying basalts was lithospheric mantle reworked by a subduction process. The basalts are subsequently overlain by tuffaceous-terrigenous and terrigenous rocks and limestones with remains of Capitanian (Middle Permian) fauna. Accessory zircons extracted from the tuffaceous-terrigenous rocks yield an U-Pb concordant age of 233.3 ± 3.3 Ma (Middle Triassic Ladinian Stage) for the youngest zircon population. The obtained data lead us to conclude that the Barabash Formation is a tectonostratigraphic rather than stratigraphic unit and may be a fragment of the Triassic accretionary wedge. The obtained data cast doubt on the accepted assignment of this unit to the Voznesenka terrane. It is more logical to include it in the Laoelin-Grodekov terrane, which represents a fragment of the Late Paleozoic active continental margin. This suggests that the boundary between these blocks should be specified and the timing of the final stage of amalgamation of the Laoelin-Grodekov terrane with the terranes of the Bureya-Khanka orogenic belt should be revised. [ABSTRACT FROM AUTHOR]

Results of a systematic paleomagnetic study are reported based on Late Carboniferous to Early Permian sedimentary rocks on the north slope of the Tanggula Mountains, in the northern Qiangtang terrane (NQT), Tibet, China. Data revealed that magnetic minerals in limestone samples from the Zarigen Formation (CP^ z)are primarily composed of magnetite, while those in sandstone samples from the Nuoribagaribao Formation (P nr) are dominated by hematite alone, or hematite and magnetite in combination. Progressive thermal, or alternating field, demagnetization allowed us to isolate a stable high temperature component (HTC) in 127 specimens from 16 sites which successfully passed the conglomerate test, consistent with primary remnance. The tilt-corrected mean direction for Late Carboniferous to Early Permian rocks in the northern Qiangtang terrane is D =30.2°, I =- 40.9°, k =269.0, α =2.3°, N=16, which yields a corresponding paleomagnetic pole at 25.7°N, 241.5°E (d p/d m=2.8°/1.7°), and a paleolatitude of 23.4°S. Our results, together with previously reported paleomagnetic data, indicate that: (1) the NQT in Tibet, China, was located at a low latitude in the southern hemisphere, and may have belonged to the northern margin of Gondwana during the Late Carboniferous to Early Permian; (2) the Paleo-Tethys Ocean was large during the Late Carboniferous to Early Permian, and (3) the NQT subsequently moved rapidly northwards, perhaps related to the fact that the Paleo-Tethys Ocean was rapidly contracting from the Late Permian to Late Triassic while the Bangong Lake-Nujiang Ocean, the northern branch of the Neo-Tethys Ocean, expanded rapidly during this time. [ABSTRACT FROM AUTHOR]

The Huashixia area in the Madoi County, Qinghai Province, western China is one of the most important areas for the studies of the formation and evolution of the A'nyemaqen mélange zone due to the well exposed, relatively complete tectonostratigraphic successions. However, the timing and evolutionary process of the A'nyemaqen paleo-ocean has long been poorly understood. Recently, we obtained abundant radiolarians from the siliceous rocks of the Maerzheng Formation of this mélange zone in Huashixia. Total 19 species in 10 radiolarian genera have been identified. They belong mainly to the Albaillellaria, Spumellaria, Entactinaria, and Latentifistularia. Four radiolarian assemblage zones are established, including: the Pseudoalbaillella rhombothoracata, Pseudoalbaillella scalprata, Ruzhencevispongus uralicus, and Follicucullus bipartitus-Follicucullus sp. cf. F. ventricosus zones. Radiolarian faunal correlations suggest a late Artinskian-early Kungurian age and late Capitanian-early Wuchiapingian age for the first two zones from the lower part and the last two zones from the upper parts of the Maerzheng Formation, respectively. All radiolarians are typical of deep water elements living in deep oceans in low latitudes during the Permian. Previously, the radiolarians of Early Carboniferous to Early Permian age and fusulinids of Early-Middle Permian age have also been reported from the A'nyemaqen mélange successions. The combination of the newly found radiolarians with the previously reported faunal and microfloral assemblages as well as radiometric ages obtained from the same stratigraphic units indicates that the A'nyemaqen paleo-ocean may have opened initially during the Early Carboniferous, expanded from the Early-Middle Permian, reached its acme in the early Late Permian, shrunk during the latest Permian to Early Triassic, and eventually was closed in the Middle Triassic. [ABSTRACT FROM AUTHOR]

The Lopingian is one of the fastest rising periods of seawater strontium isotopic ratios (Sr/Sr) in earth history, and its mechanisms and increasing rates of the Sr/Sr 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 Sr/Sr data of the Lopingian, and projected them on timescales based on evolutionary and age constrained conodonts fossils. Sr/Sr evolution vs fossil constraining timescales was re-established in this period. This research suggests: (1) Sr/Sr excursion projects on fossil zones can truly support Sr/Sr evolutionary pattern in the period; (2) Sr/Sr evolution provides a new approach for stratigraphic research of marine carbonate sections in lieu of biostratigraphic data; (3) Sr/Sr stratigraphy works on marine carbonate sections of different sedimentation rates even between different basins; (4) the Sr/Sr data and its shift was dependent on samples materials and chemical treatment methods; (5) the increasing rate of marine water Sr/Sr in the Late Permian is suggested as 5.4×10/Ma or slightly lower; (6) sedimentation age and its Sr/Sr of the Lopingian marine carbonate suggested as: D=259-( R−0.70695)/5.4×10±1 Ma. [ABSTRACT FROM AUTHOR]

A total of 48 samples of Carboniferous-Permian coal was taken from the Adaohai Mine, Daqingshan Coalfield, Inner Mongolia, China. Cu2 coal is the major coalseam of the Daqingshan Coalfield. The samples were analyzed by the ınductively coupled plasma-mass spectrometer method. The results indicate the content of V, Cr, Cu, Zn, Ga, Se, Ag, Cd, In, Ba, Pb and U of the Cu2 coals from Adaohai Mine is higher than that of the common Chinese coals. Compared to the world hard coals, the content of V, Cu, Zn, Ga, Se, Sr, Ag, Cd, In, Ba and U is relatively high. Compared to the clark values of the crust, only elements Se, Ag, Pb and Bi are enriched in the coal. Most of the elements in coal benches are lower than in those in roofs and partings. The statistical analysis and clustering analysis showed that the modes of trace elements occurrence for the Cu2 coal correlated positively with the minerals. The values of Sr/Ba show that the coal forming environment was influenced both by sea water and fresh water. [ABSTRACT FROM AUTHOR]

This work presents the first results of geochronological study of metasomatic rocks accompanying gold-bearing quartz veins of the Uryakh ore field (UOF). Based on the Rb-Sr and Ar-Ar geochronological data, it is shown that hydrothermal metasomatic processes in the ore field occurred about 280 Ma ago (Early Permian) and they are correlated with the terminal phases of formation of the Angara-Vitim batholith. [ABSTRACT FROM AUTHOR]

The depositional environment of the Upper Permian quartzose sandstone (Kuishan sandstone in Shihezi Formation of Upper Permian) in the North China epicontinental basin is controversial. In order to test the previous hypotheses, we analyzed sedimentological characteristics of the Kuishan sandstones in outcrops and boreholes, and carried out trace element geochemical analysis by electron probe microanalyzer. Three lithofacies were recognized, including normal-graded conglomerate (Cng), trough and planar cross-bedded coarse sandstone (CStpc), and planar cross-bedded medium sandstone (MSpc). Normal-graded conglomerate (Cng) formed in the meandering river or deltaic distributary channels. Trough and planar cross-bedded coarse sandstone (CStpc) formed in meandering river or distributary channels of near-source deltaic plain. Planar cross-bedded medium sandstone (MSpc) formed in the siliciclastic beach with high- to moderate-energy conditions. By the petrology and trace elements analysis, three relatively large-scale transgressions were revealed. Each transgression was reflected by the lower content of Ba and ratios of Fe/Mn, and the high content of B and ratios of B/Ga. The ratios of Ni/Co of all samples are all lower than 2, suggesting oxygen-enriched shallower water environment during deposition of the Kuishan sandstones. [ABSTRACT FROM AUTHOR]

The stratigraphy and nomenclature of the most important sections of the Kungurian Stage composed of arenaceous-argillaceous deposits in the basin of the Barda River (Perm krai, Middle Urals) are characterized using paleobotanical and palynological data. A new genus Astrogaussia Naugolnykh, gen. nov. is established for female reproductive organs of the gymnosperm order Vojnovskyales from the Carboniferous and Permian deposits of Angaraland and the Subangaran ecotonic belt, represented by headlike aggregations of sterile scales and seed stalks, with attached orthotropic seeds with a well-developed integumental wing. New combinations are proposed: Astrogaussia imbricata (Naugolnykh) Naugolnykh, comb. nov. (type species of the genus Astrogaussia), A. cristata (Neuburg) Naugolnykh, comb. nov., and A. relaxata (Radczenko) Naugolnykh, comb. nov. [ABSTRACT FROM AUTHOR]

Noeggerathiales are an extinct group of spore-bearing plants of uncertain systematic position that are known from Carboniferous and Permian age Euramerican and Cathaysian floras that occurred in present-day Europe, North America, and East Asia. The order Noeggerathiales includes over 50 species of more than 20 fossil genera, but their paleoecology is not well understood yet. Previously this group had been found only in extrabasinal floras or those inhabiting clastic wetlands. Noeggerathiales have never been recorded in coal ball floras. Thus, it is up to now uncertain whether this group has contributed to the formation of coal. Recent investigations of an Early Permian peat-forming flora of the Taiyuan Formation near Wuda, Inner Mongolia, which was preserved in a volcanic ash fall has provided evidence that noeggerathialean plants not only existed in the peat-forming vegetation but could even be the dominant group in some areas of the coal swamp. The Noeggerathiales in this particular peat-forming forest include Tingia unita, Paratingia wudensis, and a new species of Paratingia. Exceptionally well-preserved specimens indicate that these noeggerathialean plants are small trees with a canopy of compound leaves and strobili near the top of an unbranched (monocaulous) stem. [ABSTRACT FROM AUTHOR]

The Permian-Triassic effusive traps in the Kotui River valley (Siberian Platform) were studied in detail by a paleomagnetic method, resulting in a summarized magnetic stratigraphic section of the studied sequence. The presence of the reversed polarity zone corresponding to the Khardakh Formation was argued for the section basement. Inside the Kogotok Group, the boundary between the direct and reversed polarity zones occurs in the lower part of the Onkuchak Formation and mismatches the boundary between the formations of the Kogotok Group, as was accepted before. These results contradict the presence of the transition record between the direct and reversed polarity zones in basalts of the lower part of the Onkuhcak Formation. The strong transitional interval between the Ivakinsk Formation and the upper parts of the Nadezhda Formation of the Norilsk section has no analogs in the Kotui section. This means the absence of any significant volcanic activity in the Maimecha-Kotui province during the intense eruptions in the Norilsk region resulting in origination of the greater part of the lower formations of the trap sequence. These data and possible correlations of the traps of the Kotui River valley and Norilsk region indicate that the Norilsk and Maimecha-Kotui sections were temporally overlapped. [ABSTRACT FROM AUTHOR]

Reefs, both living and ancient, are extremely sensitive to environmental change. Recurrent breakdown of reef communities implies episodic occurrence of unfavorable marine conditions. An alternating succession of reef limestone with algal-foraminiferal grainstone records frequent change of Late Permian shallow-marine ecology in the Ziyun area of Guizhou Province, South China. The algal-foraminiferal grainstone interbedded in the marginal platform reef succession there has long been regarded as back-reef, lagoonal deposits, indicating lateral facies changes as the succession developed. However, our research reveals, for the first time, abundant pristine quartz crystals and volcanic glass scattered in the interbedded algal-foraminiferal layers but not in reef facies, suggesting temporal environmental changes and not a simple facies shift. Many quartz crystals form overgrowths nucleated on smaller quartz crystals; the overgrowths are diagenetic, but the nuclei are good evidence of a volcanic source. Therefore, the alternating formation of reef limestone and algal-foraminiferal limestone is interpreted as the result of episodic volcanic activity during the Late Permian. Temporary punctuations by nearby volcanic eruptions are suggested to have caused recurrent breakdown of reef communities and the occupation of reef ecological space by an algal-foraminiferal fauna. The quartz crystals are evidence that this interpretation is more likely than other controls such as sea-level changes. Cement-rich encrusted framestone (comprised of Archaeolithoporella encrusting sponge) at the top of the reef succession, as well as abundant volcanic quartz, implies that both volcanism and increased temperature may be involved in leading to the complete collapse of the reef ecosystem flourishing in Changhsingian time in South China. [ABSTRACT FROM AUTHOR]

From the Middle to Late Permian, the Laibin area in Guangxi, South China, was situated on the slope of an isolated carbonate platform, on which continuous marine successions were deposited. Two global stratotype sections for the boundary between the Guadalupian (Middle Permian) and Lopingian (Late Permian) are located at Penglaitan and Tieqiao in the Laibin area, respectively, and thus are chosen for study. At the two locations, 14 facies are recognized in the Maokou and Heshan Formations, and they are further grouped into four facies associations (basin, lower slope, upper slope, and platform margin). Six main transgressive-regressive (TR) sequences are identified in strata from the Roadian (Middle Permian) to the Wuchiapingian (Late Permian). They are conformable marine sequences that were little influenced by regional uplift (Dongwu Movement) and so provide a good record of the sea-level changes in South China at this time. Based on the significant taxonomic selection and controversial marine faunal loss in the end-Guadalupian mass extinction, and the Middle-Late Permian sea-level changes recorded by the TR sequences in the Laibin area, it is suggested that this extinction event might have been triggered by the reduction and loss of shallow-marine habitat area caused by the end-Guadalupian regression. The global cooling and Emeishan volcanism also occurring at this time could have further enhanced this extinction event. [ABSTRACT FROM AUTHOR]

Two important geological issues have a long history of debate in the Xingmeng area. The first concerns the final closure of the North China plate, Siberia plate and several intermediate massifs in the area, and the other concerns the folding and lifting of the Xingmeng Trough. Disagreements arise because of issues involving the tectonic-palaeogeographical environment of the Upper Permian deposits of the Linxi Formation. The Linxi Formation (Upper Permian) is generally considered to be either an exclusively continental deposit or separated into marine-terrigenous facies deposited during the Lower to Middle Linxi Period and continental deposits in the Upper Linxi Period. However, in this study, large numbers of bryozoan and sponge spicule fossils were discovered for this first time in the thick limestone layers and lenses of the upper part of the Linxi Formation found in the Guandi section of Linxi county in eastern Inner Mongolia. At the same time, abundant bryozoan fossils were also found in sedimentary tuff slices that were collected from the upper part of the Taohuayingzi Formation from the Taohuayingzi section in Ar Horqin Banner, and abundant small connecting body crinoid stem fossils were found in the dark shale of the Yangjiagou Formation from the Yangjiagou section of Jiutai county, Jilin Province. These marine fossils provide the first evidence that the Xingmeng area was still a marine or mainly marine environment at the end of the late Permian. This not only provides conclusive evidence for the recognition of the above two major geological issues but also promotes changes in the approach towards research, exploration and development of oil and gas, shale gas (oil), and other mineral resources that are preserved in the late Permian layers of the Northeast-Xingmeng area. [ABSTRACT FROM AUTHOR]

This paper is dedicated to the global correlation of the marine Permian-Triassic boundary layers based on some published and original data on the δC and δC values obtained for the section along the Suol Creek (Setorym River, southern Verkhoyansk region). The section includes six carbon-isotope intervals readily distinguished in the corresponding curves obtained for several Permian and Triassic reference sections in Eurasia and North America including palleontologically well substantiated sections of central Iran, Kashmir, and South China. This provides grounds for assuming the Permian-Triassic boundary's position in the Suol Creek section as being close to the carbon-isotope minimum of Interval IV. In the light of new data, the upper part of the Upper Permian Changhsingian Stage in Siberia is proposed to correspond in range to the Otoceras concavum range zone, and the lower substage of the Lower Triassic Induan Stage, to the Tompophiceras pascoei and Wordieoceras decipiens zones. The Otoceras concavum Zone of the Verkhoyansk region in its new understanding is likely correlative with the upper Changhsingian Hypophiceras triviale Zone of Greenland. Carbon-isotope intervals II, III, IV, and V defined in the Permian-Triassic boundary layers of the Verkhoyansk region, which are traceable in several reference sections of Eurasia and North America, evidently coincide with the period of some intensification of the volcanic activity in the initial late Changhsingian and with the first phases of extensive eruption of Siberian trappes in the terminal Changhsingian and initial Induan ages. New data imply the probable survival of some ammonoid species from the superfamily Otoceratoidea after the mass extinction of organisms in the terminal Permian Epoch. [ABSTRACT FROM AUTHOR]

Patterns of brachiopod paleobiogeographic regionalization in Central Asia reveal a coevolution between brachiopod paleobiogeography and tectonopaleogeography during the Early Devonian, Early Carboniferous, Late Carboniferous, Early Permian, and Middle Permian. The coevolutionary relationship reasonably accounts for the formation mechanisms of brachiopod paleobiogeography in this region, and also provides a basis for studies on the location and configuration of oceans and plates (blocks) during the late Paleozoic in Central Asia. [ABSTRACT FROM AUTHOR]

The Eumetabola (Endopterygota (also known as Holometabola) plus Paraneoptera) have the highest number of species of any clade, and greatly contribute to animal species biodiversity. The palaeoecological circumstances that favoured their emergence and success remain an intriguing question. Recent molecular phylogenetic analyses have suggested a wide range of dates for the initial appearance of the Holometabola, from the Middle Devonian epoch (391 million years (Myr) ago) to the Late Pennsylvanian epoch (311 Myr ago), and Hemiptera (310 Myr ago). Palaeoenvironments greatly changed over these periods, with global cooling and increasing complexity of green forests. The Pennsylvanian-period crown-eumetabolan fossil record remains notably incomplete, particularly as several fossils have been erroneously considered to be stem Holometabola (Supplementary Information); the earliest definitive beetles are from the start of the Permian period. The emergence of the hymenopterids, sister group to other Holometabola, is dated between 350 and 309 Myr ago, incongruent with their current earliest record (Middle Triassic epoch). Here we describe five fossils- a Gzhelian-age stem coleopterid, a holometabolous larva of uncertain ordinal affinity, a stem hymenopterid, and early Hemiptera and Psocodea, all from the Moscovian age-and reveal a notable penecontemporaneous breadth of early eumetabolan insects. These discoveries are more congruent with current hypotheses of clade divergence. Eumetabola experienced episodes of diversification during the Bashkirian-Moscovian and the Kasimovian-Gzhelian ages. This cladogenetic activity is perhaps related to notable episodes of drying resulting from glaciations, leading to the eventual demise in Euramerica of coal-swamp ecosystems, evidenced by floral turnover during this interval. These ancient species were of very small size, living in the shadow of Palaeozoic-era 'giant' insects. Although these discoveries reveal unexpected Pennsylvanian eumetabolan diversity, the lineage radiated more successfully only after the mass extinctions at the end of the Permian period, giving rise to the familiar crown groups of their respective clades. [ABSTRACT FROM AUTHOR]

Based on the paleomagnetic study of intrusive and explosive Permian-Triassic traps in the Angara River basin, Siberian Platform, it is established that the formation of the traps was marked by three short and highly intense bursts in magmatic activity, which resulted in the intrusion of three large dolerite sills (Tolstomysovsky, Padunsky and Tulunsky) and the deposition of the tuffs of the Kapaevsky Formation. These magmatic bursts occurred against the long-lived less intense background magmatism, which caused the formation of small intrusive bodies and tuff sequences. The geochronological data and correlation of the Angara traps to the effusive trap sequences in the north of the Siberian Platform (Norilsk and Maymecha-Kotuy regions) indicate that intrusion of the Tolstomysovsky sill and eruption of its comagmatic tuffs of the Kapaevsky Formation occurred in the Early Triassic. The obtained paleomagnetic data contradict the existing idea that the Padunsky and Tulunsky sills are coeval. Moreover, these data show that the magmatic bodies of different ages were mistakenly referred to the same sill. [ABSTRACT FROM AUTHOR]

This paper presents the U-Pb zircon age of pulaskite of the main phase (294 ± 1 Ma) and the rare metal syenite (283 ± 8 Ma) of the Burpala alkaline pluton. The geochronological data show that it was formed in the Early Permian. By age, it is comparable with the Synnyr pluton of the Synnyr rift zone, alkaline granitic rocks and bimodal volcanic associations of the Uda-Vitim rift zone, and carbonatites of the Saizhen rift zone of the Central Asian foldbelt. These intraplate igneous complexes were formed almost simultaneously with crustal granitic rocks of the Angara-Vitim batholite. All of this gives ground to suppose that the origination of their parental melts is a result of the influence of the mantle hot spot or mantle plume on the lithosphere that led to extensive crustal anatexis. [ABSTRACT FROM AUTHOR]

New sampling on critical intervals of the uppermost Permian and Triassic successions of the Northern Karakorum Terrain in the Karakorum Range (Pakistan) has refined the stratigraphy. Two types of successions may be distinguished in the Karakorum Range: a carbonate platform succession, spanning the whole interval from Upper Permian to Upper Triassic, possibly with several gaps; and a basinal succession, deposited from the Middle Permian to Early Carnian (Late Triassic), when the carbonate platform prograded into the basin. With the approaching and later docking of the Karakorum Block against the Asian margin closing the Paleo-Tethys, a portion of Karakorum emerged while another part subsided as a fore-deep, receiving clastics from the emerging Cimmerian Range. Molassic sediments filled the basin, whilst shallow-water carbonates transgressed over the emerged carbonate platform sometime between the latest Triassic and the Pliensbachian (Early Jurassic), with Cimmerian deformation occurring to the north. The age control is provided by conodonts, with assemblages of late Wuchiapingian, Changhsingian, Induan (Griesbachian and Dienerian), late Olenekian, early Anisian, late Ladinian, and early Carnian ages, respectively. Some information on the section around the P/T boundary is provided by palynology and isotopic C values. The dating of the Norian/Rhaetian platform is provided by foraminifers. [ABSTRACT FROM AUTHOR]

Major, trace and rare earth elements were measured in 27 samples of the Middle to Late Permian limestones from the Tieqiao section located on the marginal zone of an isolated platform (Laibin, South China). Shale-normalized REE+Y patterns of all samples show notably negative Ce anomalies (0.21-0.66, average 0.33), slightly positive Gd anomalies (1.08-1.30, average 1.20), and positive Y anomalies with superchondritic Y/Ho ratios (36-91, average 55), which are consistent with those of modern shallow seawater. Their relative LREEs enrichment with higher Nd/Yb ratios (0.58-1.80) than those of modern shallow seawater (0.21-0.50) suggests complicated sources of REEs for all samples. Compared with geochemical features of sediments influenced by terrigenous particles and hydrothermal fluids, it is concluded that ambient shallow seawater was the primary source of REEs in these limestones. Comparing the indicators of REE+Y elements (ΣREE, Nd/Yb, Ce/Ce*, Gd/Gd*, Eu/Eu* and Y/Ho) in limestones with those in bedded cherts from the Tieqiao section, we consider that limestone and bedded chert have similar sources of REE+Y elements: ambient shallow seawater with more or less hydrothermal fluids. In addition, there is a completely negative correlation between CaCO and SiO contents in limestones and bedded cherts. These results imply that precipitation of CaCO was inhibited by that of SiO which was derived mainly from hydrothermal fluid, especially in bedded cherts from the Tieqiao section. [ABSTRACT FROM AUTHOR]

Alkali-rich dykes of the Late Permian in Ulungur (乌伦古) area are representative products of granitic magmatism in the evolution of the Paleozoic orogenic belt in the East Junggar (准噶尔), North Xinjiang (新疆). We selected two representative samples for geochemical analysis (major and trace elements), and twenty-two zircon grains for zircon dating. Isoplot (ver3.0) was used to calculate isotopic age and make concordia diagrams. This study shows that the trachy porphyry dykes, featuring low concentration of AlO, CaO, MgO and high alkali contents, are metaluminous alkaline rock and belong to A-type granitoids. The dykes have low concentration of the REE and incompatible elements, and the REE patterns show clear negative Eu anomalies (δEu=0.74-0.58), enriched LREE (LREE/HREE>4, (La/Yb)=5.97-4.63) and undifferentiated HREEs. Similar normalized REE and incompatible element patterns are also showed in the dykes from Yemaquan (野马泉) and granites from Ulungur, suggesting that they are possibly originated from the same source and formed in the same tectonic environment, but the trachy porphyry dykes are more evolved. The age of the trachy porphyry dykes is 255.3±2.4 Ma, which is probably the crystallization time of the trachy porphyry. The dykes formed in late-orogenic phase of post-collision process or within-plate environment, which suggested that the trachy porphyry dykes possibly crystallized in the transition period during which the tectonic setting changed from post-collision to within-plate environment. So we consider that the age when the post-collision ended and the crustal cratonization begun in the East Junggar is 255 Ma, Late Permian. [ABSTRACT FROM AUTHOR]

The Val Daone Conglomerate (VDC) is a continental clastic unit that crops out eastwards of the central Southern Alps, from the NE sector of the Collio Basin to the W as far as the Tione Basin to the E. This significant but as yet relatively unknown formation lies just above the regional unconformity that marks the boundary between the two Permian major tectono-sedimentary cycles (TSU1 and TSU2) and grades upwards paraconformably (?) to the fluvial red beds of Verrucano Lombardo/Val Gardena Sandstone, generally associated with Late Permian times. Recent palynological investigations on the VDC suggested a Guadalupian age (late Roadian-early Wordian), owing to the remarkable presence of diversified pollen associations; therefore, this sedimentary unit is to date the first one ascribed, on a palaeontological basis, to the Middle Permian in the entire Southern Alps domain. A detailed facies analysis of VDC shows deposition in amalgamated alluvial fan-braided and fluvial environments with wide channels and longitudinal bars. In its type area and Val Rendena, the VDC rests unconformably above the last volcanic episode of the TSU1. LA ICP-MS U-Pb dating on zircon from two samples of such topmost Lower Permian volcanic rocks, known as Ponte Murandin dacitic lava and Malga Plan rhyodacitic Ignimbrites (Tione Basin), provided Concordia ages of 278 ± 2 Ma (MSWD = 0.01) and 279 ± 2 Ma (MSWD = 0.16), respectively. As well as allowing us to better define the duration of the time gap between the two Permian megacycles in the central Southern Alps in almost 10 Ma, these radiometric age determinations are also significant because they enable us to regionally link the coeval volcanic bodies which crop out in the Collio Basin to the SW and in the 'Athesian Volcanic Group' to the NE, respectively. [ABSTRACT FROM AUTHOR]

Fusulinids from the Chili Formation are studied in the Rahdar section of the Kalmard block west of the town of Tabas, Central Iran. The Kalaktash and Halvan fusulinid complexes are revealed in the section. The location of the Halvan complex over the Kalaktash one confirms its relatively younger (Late Sakmarian-Early Artinskian) age. The Halvan complex was previously considered to be Asselian. Three new species ( Parazellia rahdarensis, Nonpseudofusulina bozorgniai, and Eoparafusulina rahdarensis) and one new subspecies ( Benshiella khorasanensis compacta) are described. [ABSTRACT FROM AUTHOR]

Three pigmented strains of halophilic archaea (RS75, RS77, RS79) were isolated from the monoliths of mottled sylvinite from the Verkhnekamsk salt deposit (Solikamsk, Russia). The cells were nonmotile, gram-negative, pleomorphic, disk-shaped or ovoid, 0.8-1.0 × 1.5-2.5 μm. The organism was a chemoorganotrophic obligate aerobe producing catalase and oxidase. A number of carbohydrates and carboxylic acids were used as growth substrates. Growth occurred in the presence of 7-27 % NaCl (with the optimum at 15-18 %), 0.02-20 % KCl (0.2-1 %), 0.2-16 % MgCl (2-3 %), in the temperature range from 23 to 51 °C (40-45 °C), and pH 5.5-8.0 (6.8-7.0). The membranes contained carotenoids of the bacterioruberin series. Phosphatidylglyceromethylphosphate (PGP-Me), phosphatidylglycerol (PG), sulfated diglycosyl diether (S-DGD-1) predominated among the polar lipids. The DNA G + C content was 64.0-65.0 mol %. Phylogenetic analysis of the 16S rRNA gene sequences showed high similarity of the new strains to Haloferax species: H. denitrificans (99.2 %) and H. volcanii (99.1 %), H. larsenii (96.9 %) and H. elongans (96.6 %). DNA-DNA hybridization revealed 93-95 % similarity between strain RS75 and strains RS77 and RS79; the similarity levels between strain RS75 and the type strains of Haloferax denitrificans VKM B-1754 and Halobacterium salinarum VKM B-1769 were 50 and 10 %, respectively. According to its phenotypic and genotypic characteristics, the organism was classified as a member of the genus Haloferax, forming a new species with the proposed name Haloferax chudinovii sp. nov. type strain is RS75 (=VKPM B-11279). [ABSTRACT FROM AUTHOR]

The problems of the intra- and regional correlation of Permian sections of Northeastern Asia are considered based on a new zonal biostratigraphic bivalve scale. The interregional correlation was performed for the Permian deposits in the eastern part of the Boreal Superrealm and some adjacent regions. The possibilities and problems of bivalve-based correlation of Permian sediments in extraboreal regions are discussed. [ABSTRACT FROM AUTHOR]

Six assemblages of smaller foraminifers are first distinguished and described from sections of the Kalmard tectonic block, Central Iran. The assemblages that have been studied are correlated with concurrent assemblages from the East European platform, Cis-Urals, Darvaz, Northern Pamir, and some other regions of the Tethyan Realm. The results of correlation and available data on fusulinids and conodonts occurring in association with smaller foraminifers are used for dating the assemblages whose distribution ranges span the stratigraphic interval from the early Sakmarian (lower assemblage) up to the Kubergandian (uppermost assemblage). New species Frondina iranica sp. nov. discovered in the study region is described. [ABSTRACT FROM AUTHOR]

The Early Permian Gondwana regime succession of the Nilawahan Group is exposed only in the Salt Range of Pakistan. After a prolonged episode of non-deposition that spanned much of the Palaeozoic, the 350 m thick predominantly clastic sequence of the Nilawahan Group records a late glacial and post-glacial episode in which a range of glacio-fluvial, marine and fluvial environments evolved and accumulated. The Early Permian succession of the Salt Range has been classified into four formations, which together indicates a changing climatic regime during the Early Permian in the Salt Range region. The lower-most, Tobra Formation unconformably overlies a Cambrian sequence and is composed of tillite, diamictite and fresh water facies, which contain a floral assemblage ( Gangamopteris and Glossopteris) that confirms an Asselian age. The Tobra Formation is overlain by marginal marine deposits of the Dandot Formation (Sakmarian), which contain an abundant brachiopods assemblage ( Eurydesma and Conularia). Accumulation of the Dandot Formation was terminated by a regional sea-level fall and a change to the deposition of the fluvial deposits of the Warchha Sandstone (Artinskian). The Warchha Sandstone was deposited by high sinuosity meandering, avulsion prone river with well developed floodplains. This episode of fluvial sedimentation was terminated by a widespread marine transgression, as represented by the abrupt upward transition to the overlying shallow marine Sardhai Formation (Kungurian). The Early Permian Gondwana sequence represented by the Nilawahan Group is capped by predominantly shallow shelf carbonate deposits of the Tethyan realm. The sedimentologic and stratigraphic relationship of these four lithostratigraphic units in the Salt Range reveals a complex stratigraphic history for the Early Permian, which is mainly controlled by eustatic sea-level change due to climatic variation associated with climatic amelioration at the end of the major Gondwana glacial episode, and the gradual regional northward drift to a lower latitude of the Indian plate. [ABSTRACT FROM AUTHOR]