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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]

Sardinia (Italy) represents one of the most comprehensive cross-sections of the Variscan orogen. The metamorphic and structural complexity characterizing its axial zone still presents many unresolved issues in the current state of knowledge. The data presented from the structural study of the entire axial zone of this area have allowed the authors to propose a subdivision into two new structural complexes. In particular, a younger complex is identified as the New Gneiss Complex, containing remnants of an older and higher-grade metamorphic complex defined as the Old Gneiss Complex. The structural and geometric relationships between the two complexes suggest the redefinition of the axial zone of Sardinia as part of the intracontinental East Variscan Shear Zone/medium-temperature Regional Mylonitic Complex. Comparable relationships are also highlighted in many other areas of the Variscan chain (e.g., Morocco, Corsica, Maures Massif, and Argentera Massif). Extending this new structural interpretation to other axial zones of the South European Variscan orogen could provide new hints for reconstructing the collision boundaries between Gondwana and Laurussia in the late Carboniferous to the early Permian periods. [ABSTRACT FROM AUTHOR]

The Permian to Triassic period represents a pivotal phase in the evolution of the Paleo-Asian Ocean, marked by significant tectonic transitions from subduction, collision, and post-orogenic extension. The timing of closure of the Paleo-Asian Ocean in northeastern China has always been controversial. In this contribution, the petrology, zircon U-Pb geochronology and geochemistry are conducted on granite found in well HFD1, Songliao Basin, eastern part of Central Asian orogenic belt. Zircon U-Pb dating indicates that granite crystallized at 258.9 ± 2.2 Ma, as the product of magmatism occurred in the early Late Permian. The rocks have high SiO2, Al2O3, Na2O content, negative Eu anomaly, light enrichment of rare-earth elements, depletion of heavy rare-earth elements, high Sr (448.29–533.11 ppm, average 499.68 ppm), low Yb (0.49–0.59 ppm, average 0.54 ppm), Y (4.23–5.19 ppm, average 4.49 ppm), and high Sr/Y ratios (98–125, average 112) and can be classified as O-type adakite. This is the first discovery of late Paleozoic adakite in the Songliao Basin and the neighboring areas. The geochemistry of adakite indicates derivation by partial melting of MORB-type subducted oceanic crust, indicating that the subduction of the Paleo-Asian Oceanic lithosphere lasted until at least 258.9 Ma. [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]

The Boda Claystone Formation (BCF) is an extended sedimentary sequence formed in a shallow-water salt lake under semi-arid to arid climatic conditions during the middle Permian period. The rock was formed predominantly from denuded and altered products of three primary felsic sources, the Mórágy Metagranite Complex, the Baksa Metamorphic Complex and the rhyolitic Gyűrűfű Formation, resulting in the recent dominant sheet silicate components, illite and chlorite. BCF has been considered a potential host rock for high-level nuclear waste, too. Thus, it has been characterized by several powerful methods so far (X-ray diffraction (XRD), transmission electron microscopy (TEM), etc.). 57Fe Mössbauer spectroscopy may provide a unique additional tool to study iron-bearing minerals. Iron is dominantly present in a ferrous form in minerals of the fresh parent rocks (in the biotite group and amphibole), and in a ferric oxide, hematite, in altered Gyűrűfű Formation. During transformations of biotite group minerals and amphibole, the partial release of ferrous iron or its conversion to ferric form takes place with the stabilization of recent illite and chlorite, while the original layered structure is still preserved. Mössbauer spectroscopy revealed the dominant presence of ferrous iron located in cis-M2 octahedral sites both in parent biotite group minerals and in the final illite, as well as chlorite in both stages. The proportion of ferrous iron in biotite group minerals was halved during the stages of evolution by conversion to ferric iron still in sheet silicate illite or by segregation into separate hematite inclusions. The transformation process of biotite group minerals and amphibole of the source rocks is connected only to the iron-bearing smaller fraction of sheet silicates in the BCF clay mineral assemblage. Determination of Fe2+/Fe3+ ratios in sheet silicates was also pertinent in two sections of BCF. Namely, in samples from the Gorica region, Fe3+ was dominant, siting in illite, whereas Fe2+ was also present in significant portions in chlorite in samples from the Western Mecsek Anticline. The interpretation is deduced in correspondence with results of extended XRD, and high-resolution TEM studies. [ABSTRACT FROM AUTHOR]

This article examines the geotectonic and sedimentary features of the Upper Devonian–Carboniferous–Permian deposits of the North Caspian basin, represented by deposits of marine Paleozoic-isolated carbonate platforms formed during the subsidence of the basement on the passive continental margin. The top is covered by thick salt-bearing Kungurian deposits from the end of the Early Permian epoch. The formation of carbonate platforms is associated with a major tectonic restructuring of the basin at the turn of the Caledonian and Hercynian eras, when the Paleo-Tethys Ocean was formed and isolated carbonate islands began to grow in an open marine environment. The central part of the depression experienced a long and gradual subsidence that spanned the entire Paleozoic era and the beginning of the Mesozoic era. In the south and east, from the Devonian to the Permian periods, barriers were formed in the form of island carbonate massifs that separated the North Caspian basin from the Paleo-Tethys Ocean. During the formation of the salt-bearing basin, these barriers limited water exchange and ensured a one-way influx of sea water from the open ocean. As a result, at the end of the Permian period, thicker salts accumulated; however, during the collision of the continental massifs, an invasion of many kilometers of redbeds occurred. They initially stopped salt accumulation; however, gradually, in the north of the Caspian Sea during Roadian times, the salt accumulation continued. The post-Roadian time is associated with the influx of large quantities of redbed sediments, which caused gravitational instability in the underlying salt, and salt tectonics began with the formation of domal structures. [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 interest and importance of studying the reproductive strategies of Palaeozoic plants are growing. Fossil seeds play an essential role in this line of study, as they are widely described from different sedimentary formations throughout the Permian period. The Indian Permian Seed Database (IPSD) software will be an information system for ensuring the storage, safety, accessibility and recovery of the details of Indian Permian seed records in a selective manner. The current database includes 28 genera and 44 species of compressed seeds described from Lower Gondwana (Permian), with all the details for researchers. The software provides options for addition, deletion, modification and search facility. The search also includes different options (single or combination). It is a quick and organised way to look for seeds, especially on a data grid for information about seeds that have already been published in the same or different sediments. IPSD is a tool for the computer-based identification of seeds and distinguishing different genera or species within the same category. It is user-friendly and provides updated knowledge of seeds from the Lower Gondwana basins of India. It provides morphotaxonomical characters, distribution and photo documentation of seeds. The software increases accuracy through computerassisted identification of seeds. Hence, reducing and curtailing unnecessary information while describing a new species with inadequate earlier knowledge of Permian seeds. [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]

The basic research on the separation method and characteristic properties of different coal lithotypes is of great significance for coal precision utilization. Based on the separation process of coal lithotypes and the characterization of the physical and chemical properties of the separation products, this paper aims to explore the relationship between the selection of lithotypes differential separation methods and their own physical and chemical properties. Firstly, a combined process of manual picking, density liquid centrifugation and shaking table separation was used to separate and purify fusain, vitrain and durain. Then, the properties of high purity single lithotype (fusain: 88.95%, vitrain: 91.74%, and durain: 85.33%) are analyzed to micromorphology analysis, surface properties, thermal stability analysis, elemental composition and functional group analysis. The product characterization results showed that the difference some physical and chemical properties, thermogravimetric parameters, surface finish and flatness, surface wettability, elemental content (C, O, S), degree of aromatization, and oxygen-containing functional, are obviously different and have certain internal correlation for different coal lithotypes. Comprehensive comparative analysis demonstrated that several parameters (the degree of surface finish and aromatization, as well as the content of oxygen-containing functional groups) have significant positive effects on wettability of coal lithotypes. These properties determine that the separation methods of different lithotypes should be different. Besides, we also verify the above conclusion through the combined separation process experiment of centrifugation, flotation and shaking table. [ABSTRACT FROM AUTHOR]

​​​​​​​We held the MagellanPlus workshop SVALCLIME "Deep-time Arctic climate archives: high-resolution coring of Svalbard's sedimentary record", from 18 to 21 October​​​​​​​ 2022 in Longyearbyen, to discuss scientific drilling of the unique high-resolution climate archives of Neoproterozoic to Paleogene age present in the sedimentary record of Svalbard. Svalbard is globally unique in that it facilitates scientific coring across multiple stratigraphic intervals within a relatively small area. The polar location of Svalbard for some of the Mesozoic and the entire Cenozoic makes sites in Svalbard highly complementary to the more easily accessible mid-latitude sites, allowing for investigation of the polar amplification effect over geological time. The workshop focused on how understanding the geological history of Svalbard can improve our ability to predict future environmental changes, especially at higher latitudes. This topic is highly relevant for the ICDP 2020–2030 Science Plan Theme 4 "Environmental Change" and Theme 1 "Geodynamic Processes". We concluded that systematic coring of selected Paleozoic, Mesozoic, and Paleogene age sediments in the Arctic should provide important new constraints on deep-time climate change events and the evolution of Earth's hydrosphere–atmosphere–biosphere system. We developed a scientific plan to address three main objectives through scientific onshore drilling on Svalbard: Investigate the coevolution of life and repeated icehouse–greenhouse climate transitions, likely forced by orbital variations, by coring Neoproterozoic and Paleozoic glacial and interglacial intervals in the Cryogenian ("Snowball/Slushball Earth") and late Carboniferous to early Permian time periods. Assess the impact of Mesozoic Large Igneous Province emplacement on rapid climate change and mass extinctions, including the end-Permian mass extinction, the end-Triassic mass extinction, the Jenkyns Event (Toarcian Oceanic Anoxic Event), the Jurassic Volgian Carbon Isotopic Excursion and the Cretaceous Weissert Event and Oceanic Anoxic Event 1a. Examine the early Eocene hothouse and subsequent transition to a coolhouse world in the Oligocene by coring Paleogene sediments, including records of the Paleocene–Eocene Thermal Maximum, the Eocene Thermal Maximum 2, and the Eocene–Oligocene transition. The SVALCLIME science team created plans for a 3-year drilling programme using two platforms: (1) a lightweight coring system for holes of ∼ 100 m length (4–6 sites) and (2) a larger platform that can drill deep holes of up to ∼ 2 km (1–2 sites). In situ wireline log data and fluid samples will be collected in the holes, and core description and sampling will take place at The University Centre in Svalbard (UNIS) in Longyearbyen. The results from the proposed scientific drilling will be integrated with existing industry and scientific boreholes to establish an almost continuous succession of geological environmental data spanning the Phanerozoic. The results will significantly advance our understanding of how the interplay of internal and external Earth processes are linked with global climate change dynamics, the evolution of life, and mass extinctions. [ABSTRACT FROM AUTHOR]

The Fengcheng Formation of the Mahu Sag is an unconventional reservoir that is of paramount importance for exploration and development of hydrocarbon resource. However, current research on natural fractures in the Fengcheng Formation remains limited, posing challenges for exploration of hydrocarbon resource in the region. This study is based on core observations, thin section identification, geochemical testing and the evolution of regional tectonic movements to investigate the characteristics and periods of formation of natural fractures to address this gap. According to the characteristics of natural fractures in the drilling core samples and microsections, the natural fractures in the Fengcheng Formation can be grouped into structural fractures and atectonic fractures. Structural fractures can be further divided into three subtypes: high-angle interlayer shear fractures, along-layer shear fractures, and tensile fractures. Additionally, non-tectonic fractures in this studied area are primarily bedding fractures, hydraulic fractures, and hydrocarbon-generating overpressure fractures. Vertically, fracture development is more prominent at the bottom of Feng #2 Formation and at the top of Feng #3 Formation. Results also indicate that natural fractures primarily formed during three distinct tectonic movement periods. The initial stage of fracture evolution pertains to the Late Permian period (243–266 Ma), filled with fibrous calcite, and exhibiting a uniform temperature of 70–100 °C. The second stage of fracture evolution occurred during the Late Indosinian to Early Yanshanian period (181–208 Ma), mostly filled or semi-filled with calcite, with a uniform temperature of 110–130 °C. The third stage of fracture development happened during the late Yanshanian to early Himalaya period (50–87 Ma), predominantly filled with calcite, and presenting a uniform temperature of 130–150 °C. Among the various types of structural fractures, the density of high-angle interlayer shear fractures demonstrates a positive correlation with daily gas production, indicating their vital role in promoting hydrocarbon resource production and transportation. Furthermore, microfractures generated by hydrocarbon-generating overpressure fractures exhibit small pore sizes and strong connectivity. These microfractures can create an effective permeability system by connecting previously isolated micropores in shale reservoirs, thus establishing interconnected pore spaces in the shale formation. [ABSTRACT FROM AUTHOR]

KLR‐1 scientific deep borehole, drilled in the 1993 Killari earthquake region of Maharashtra (India), penetrated 8 m thick infratrappean sediments below a 338 m‐thick column of Deccan volcanics that rested over Neoarchean amphibolite to granulite facies mid‐crustal basement. Detailed palynological studies revealed the presence of characteristic Gondwana palynomorphs in sedimentary succession that include Plicatipollenites indicus, P. trigonalis, Parasaccites korbaensis, P. diffusus, Microbaculispora indica, Cyclobaculisporites minimus, Cyclogranisporites barakarensis, C. gondwanensis, Jayantisporites pseudozonatus, Leiosphaeridia bokaroensis, Latosporites sp., Verrucosisporites sp., cf. V. ambiplicatus and Striatopodocarpites gondwanensis. Qualitative analyses of palynomorphs would suggest an Asselian age (298–295 Ma) for their formation and burial in dysoxic to anoxic conditions. Recorded palynological assemblages correlate well with continental Lower Gondwana (Early Permian) sediments of India, as well as other Gondwana continents, indicating a larger extent of Gondwana sedimentation than hitherto known today. Petrological studies indicate the presence of two types of carbonate units that overly the crystalline basement. A relatively coarse‐grained sparry carbonate rock immediately overlies the basement (Sample KIL‐7). The size of the carbonate crystals in the sparite vary from 100 to 500 μm. This unit is overlain by an extremely fine‐grained micrite resembling lime mud (Sample KIL‐6). Micrite is made of carbonate grains with an average size of 10 μm. X‐ray diffraction studies indicate that calcite is the dominant carbonate mineral, while dolomite and quartz occur in minor amounts. Geochemical analyses indicate that in these two samples of carbonate rock that overlie the basement, CaO (33.38 to 38.16 wt %) is higher than MgO (16.0–23.85 wt%). These infratrappeans sediments are also characterized by stable carbon (δ13C) and oxygen (δ18O) isotopic ratios ranging from −1.59 to −8.74‰ and −9.12 to −13.50‰ versus PDB, respectively, thereby conforming to non‐marine fresh water deposits. These findings provide first evidences of reactivation and rifting of Dharwar intracratonic regions during earliest Permian Gondwana Period, which led to severe lithospheric mantle destruction, and massive regional uplift and erosion of the granitic‐gneissic upper crust. Large scale inland‐rifting during the Gondwana sedimentation period was possibly a prelude to India‐Antarctic breakup during the early Cretaceous. [ABSTRACT FROM AUTHOR]

The mass extinction at the end of the Permian period was a time of considerable ecological upheaval. A new study shows that in Southern Africa top predators replaced each other in succession across the end-Permian interval, suggesting that ecological crisis preceded the mass extinction. [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]

India has a huge reserve of coal belonging to Permian Period. 85% of these coals fall under non-coking category and are being used for power generation. Looking at the depletion of coking coals, there is a huge challenge for the Indian steel industry to manufacture coke using domestic coals. Utilizing Indian non-coking or inferior coals for coking purpose is a challenging task because of its higher ash content and poor rheological properties. These coals are less matured than coking coals and contain higher amount of organic and inorganic inerts. To study the effect of blending Indian thermal coals on coke CSR, eight different coals of varying characteristics have been used for experimentation. To improvise their coking ability and resulting coke strength on carbonization, phenol formaldehyde-based polymer addition has also been tried and tested. In most of the cases, it has been found that CSR got improved because polymer acts as a catalyst and improves the binding behavior and rheological property of the coal blend. Present work suggests that Indian thermal coals can be used up to 10% as one of the component coals in the blend for coke making with polymer addition. [ABSTRACT FROM AUTHOR]

The late Palaeozoic continental-arc magmatic rocks in the Gongzhuling area are located in the Liaoyuan Accretionary Belt. Here we present new zircon U–Pb ages, whole-rock major- and trace-element compositions, Li and zircon Hf isotopic compositions and oxygen fugacity of these rocks with an aim to constrain the lithium isotopic composition of the source region and origin of the magmas. These rocks were formed during 269–258 Ma in middle–late Permian time. The dioritic rocks were formed through mixing processes, with the mafic melts originating from a metasomatized mantle wedge and the felsic melts from the lower crust of a Neoproterozoic arc. The mantle wedge has been metasomatized by Li-rich fluids derived from subducted oceanic crust, as indicated by the δ7Li values of +0.4 ‰ to +3.5 ‰ and positive ϵHf(t) values (+0.7 to +13.1). Redox-sensitive Ce in the zircons indicates the f O2 of the magmas to be low to intermediate (FMQ−2.2 to FMQ+2.6; FMQ is the fayalite–magnetite–quartz redox buffer), precluding large-scale porphyry Cu–Mo mineralization. The middle–late Permian magmatic rocks represent the terminal magmatic record of the subduction of the Palaeo-Asian oceanic crust, meaning that the final closure of the Palaeo-Asian Ocean in the eastern Central Asian Orogenic Belt occurred at the end of the Permian Period. Recent identification of Mesoproterozoic (c. 1400 Ma) granites suggests some Palaeoproterozoic crustal fragments still exist in the Liaoyuan Accretionary Belt, but only in a small amount; therefore, it is concluded that the crustal growth of the Liaoyuan Accretionary Belt occurred mainly during the Neoproterozoic period. [ABSTRACT FROM AUTHOR]

The West Bogda Mountains separate the two largest petroliferous sedimentary basins in Northwest (NW) China and may record the evolution history of the Central Asian Orogenic Belt (CAOB). The timing of the initial uplift of the West Bogda Mountains is debated, which may provide the robust constraint on the CAOB evolution. Here we present an integrated study of sedimentology, geochemistry, and detrital zircon geochronology to constrain the timing of the initial uplift of the West Bogda Mountains. The late Lower Permian Lucaogou Formation in the West Bogda Mountains is dominated by organic-rich laminated shale, gravity flow deposits and dolomite without shallow-water sedimentary structures, suggesting a deep-water lacustrine depositional environment. The Middle Permian Quanzijie Formation is mainly composed of poorly sorted and sub-rounded conglomerate, which indicates that the depositional environment changed to an alluvial fan. The depositional environment changed to a meandering river system in the early Upper Permian Wutonggou Formation, with evidence from the widely developed cross-bedding in its sandstone and the typical 'dual structure'. The compositions of immobile elements and detrital zircon U-Pb geochronology reveal changes in sediment sources from the early to late Permian. The sediments of the late Lower Permian Lucaogou Formation were mainly sourced from the North Tianshan, while the sediments in the Middle Permian were mostly locally derived. Combining these evidences, we infer that the initial uplift of the West Bogda Mountains likely occurred in the period from the late Lower to Middle Permian (~289.8 Ma to ~265.7 Ma), and was probably caused by the intracontinental collision between Junggar Block in the north and the Tarim Block in the south. [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]

Simple Summary: Two new representatives of the blattinopsid genus Glaphyrophlebia, from the Gzhelian of Southern France and Spain, respectively, are described and illustrated. They suggest that the diversity of this genus began to increase during the latest Carboniferous, possibly in relation to the climatic changes occurring at that time. Glaphyrophlebia victoiriensis sp. nov. (Paoliida: Blattinopsidae) is the third Gzhelian representative of the genus and is described based on a beautiful forewing from the Var department in Southern France. Together with the description of another forewing fragment of a Glaphyrophlebia sp. from the Province of León in NW Spain, they improve our knowledge of fossil insects from French and Spanish upper Carboniferous deposits. The specimen of Glaphyrophlebia sp. is the first mention of the family in the Carboniferous of Spain and extends the geographical distribution of the genus. These descriptions suggest that the genus Glaphyrophlebia was speciose during the Upper Pennsylvanian, while otherwise very diverse in the lower and middle Permian strata of the Russian Federation. We proposed the first hypothesis to explain the diversification of the family and of its most speciose genera and to argue that their diversity dynamics were likely linked with the major environmental changes that followed the collapse of the Carboniferous rainforest, notably the extension of arid biomes during the Permian period. The exquisite preservation and the fineness of the sediment from Tante Victoire, in which the new species was found, suggests that the locality is suitable for preserving other fossil insects and will require additional investigations. [ABSTRACT FROM AUTHOR]

We present the first palynological assemblages collected from the fine-grained variegated beds that overlie the De La Cuesta Formation at Puerta de Las Angosturas, Sierra de Narváez, Catamarca Province, Argentina. Five samples from two different stratigraphic levels provided spores, non-taeniate, taeniate, and sulcate pollen grains referred to the Lueckisporites/Weylandites (LW) Biozone. The palynofloras are equivalent to those previously reported for the Los Jumes area and, therefore, the variegated sequences that overlie the De La Cuesta Formation at both flanks of the Sierra de Narváez are entirely equivalent, not only lithologically but also in fossiliferous content and age. These assemblages are analogous to those isotopically dated at 278.84±0.22 Ma (Kungurian) in the Valle Hermoso area (La Rioja Province), which constitute a key stratigraphic horizon to link the initial phases of the Permian volcanic arc and the sedimentation in the retroarc basins. The recognition of diagnostic taxa of the LW Biozone confirms earlier correlations with the Striatites Biozone of the Chacoparaná Basin and the Lv Biozone from Brazil. The different ages recently reported for the succession analyzed here in Sierra de Narváez and La Veteada Formation, suggest that these units should not be correlated. Moreover, while the strata overlying the De La Cuesta Formation records the Permian postorogenic sedimentation in the Paganzo Basin, the La Veteada Formation accounts for the transition to the rifting conditions that characterized the triassic basins of northwestern Argentina. [ABSTRACT FROM AUTHOR]

"The Falls of Wichita Falls: An Environmental History of the Red Rolling Plains" by Jahue Anderson is a book that explores the complex relationship between the dreams of city boosters and the challenging environmental conditions of the region. The book focuses on the geography, climate, geology, and history of the Red Rolling Plains, which are characterized by aridity, salinity, tornadoes, and floods. The author uses the story of President Theodore Roosevelt's wolf hunt in 1905 as a starting point to discuss the region's environmental history. The book also delves into the impact of development, engineering failures, water management, and the salt problem in the area. Ultimately, the author presents a cautionary tale of failed ideologies, dysfunctional administration, and poor leadership, highlighting the challenges of negotiating with nature in the Red Rolling Plains. [Extracted from the article]

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]

Although chert deposits are limited in geological distribution, their geological and geochemical characteristics can provide important information to reconstruct paleoenvironmental and diagenetic processes. For the Permian period, cherts are utilized to trace global silicon cycles and hydrothermal activities in relation to the Permian Chert Event. In Northwest China, Permian chert nodules have recently been discovered in both the southeastern and northwestern margins of the Junggar Basin. We conducted an analysis of the mineralogy, petrology and geochemistry of chert nodules of the Lucaogou Formation in the southeastern margin of the Junggar Basin to identify silicon sources and determine the precipitation mechanism of chert nodules. As evidenced by petrology, the chert nodules were mainly composed of crypto-microcrystalline silica (94.33% on average), with development of a soft-sediment deformation structure, indicating the synsedimentary deposition of silicon. Proven by trace elements, high Eu/Eu* ratios (average 2.14), low total rare earth element content (average 6.03 ppm), low LaN/YbN ratios (average 0.17) and low Y/Ho ratios (average 25.25) in chert nodules supports the hydrothermal source of silicon. The wide distribution of authigenic metal-bearing minerals and the significant positive Eu anomalies observed suggest that the chert depositions in the Lucaogou Formation intermittently received high-temperature (>250 °C) hydrothermal fluids, likely associated with the initiation of the Bogda Rift in the middle Permian. Following rapid cooling down and differential compaction, siliceous sediments dehydrated and deformed, finally forming chert nodules. [ABSTRACT FROM AUTHOR]

The Carboniferous–Triassic period was an important stage of global sea–land transformation, with coal formation in the Carboniferous, biological extinction at the end of the Permian, and global drought in the Triassic. The MS-1 well in the Mosuowan High of the Junggar Basin is the deepest well drilled in Northwestern China. In this paper, we investigate the sedimentary environment and climate evolution of the Mosuowan area in the central Junggar Basin during the Late Carboniferous–Early Permian by the petrothermal, lipid biomarker, and isotopic composition of mud shale core samples, and explore the tectonic–climatic events and Central Asian orogenic belt evolution driving the sedimentary environment. The study shows that the organic matter from the Upper Carboniferous to the Lower Permian is at a mature stage, but biomarkers maintained the primary information although the organic matter was subjected to thermal evolution. In the late Carboniferous period (Tamugan Formation), the study area was a closed remnant sea with a relatively humid climate, triggering lush terrestrial vegetation and high organic carbon content in the sediments, which had the potential to evolve into natural gas. During the Xiazijie Formation of the Middle Permian, tectonic activity shifted to the subsidence period, and the salinity of the water decreased after a large input of fresh water. The lake basin area expanded, and the content of aquatic organisms continued to increase. As the Lower Permian stratigraphy is missing, this sea–land transition seems to jump. The low and upper Urho Formations of the Middle–Upper Permian are a deltaic foreland deposit, and geochemical indicators show an overall lake retreat process with a continuous increase in organic matter content of terrestrial origin. The lithologic assemblage of the Triassic Baikouquan Formation is braided river deltaic sedimentation with migration of deposition centers of the lake basin. In conclusion, the Late Carboniferous–Early Permian period was influenced by global changes, Paleo-Asian Ocean subduction, and continental splicing, which resulted in a continuous increase in terrestrial organic matter, water desalination, and oxidation-rich sediments in the Mosuowan region, but the P–T biological mass extinction event was not recorded. [ABSTRACT FROM AUTHOR]

The Palaeo‐Tethys is known to have diverged into several splays throughout East and South‐east Asia. Several researchers have widely studied the importance and geometries of the Palaeo‐Tethys' branches. Plate reconstruction geometries for the southern Palaeo‐Tethys splay suggest that the ocean either connects to the proto‐Pacific or dies out. We review and discuss the Late Palaeozoic to the Early Mesozoic lithologies attributed to the Palaeo‐Tethys, from the Himalayan Syntaxis in the north to the Bangka and Belitung islands in western Indonesia to the south. Relics of oceanic crust and deep‐sea sediments related to the main Palaeo‐Tethys Basin can be traced from the South China (Yunnan)‐Thailand border to Peninsular Malaysia. A sub‐parallel back‐arc suture exists in eastern Thailand in the north and vanishes towards the south at the latitude of the Gulf of Thailand. Towards the south of Peninsular Malaysia, the material that constitutes the suture zone of main Palaeo‐Tethys is found offshore in the Riau Archipelago, Indonesia, and has been extensively eroded. Thus, we rely on gravity signatures to extrapolate the extension of the structures to the Bangka and Belitung islands, which show only minor serpentine and pillow basalts occurrences along a line that curves towards Borneo. The metamorphic rocks associated with the suture zones range from high grade (gneiss) in Thailand to low grade (mica schist and minor amphibolite) in Peninsular Malaysia. The syn‐ and post‐collisional granitic bodies that form large batholiths in Thailand and Malaysia are comparatively smaller in Indonesia, particularly on Belitung Island, suggesting the lack of large underplating of the Sibumasu crust within the region. We interpret the stratigraphic and tectonic observations of the southern Palaeo‐Tethys to support the theory of the southward (present orientation) opening of a propagating oceanic basin from Devonian to Carboniferous, which began to close from the Permian to Triassic period. [ABSTRACT FROM AUTHOR]

Based on 2D and 3D seismic data, the latest drilling data and field outcrop data of the northern slope of the Central Sichuan paleo‐uplift, the structural analysis method is used to analyze unconformity development characteristics and fault characteristics during the key structural transformation period, discussing the influence of the structural characteristics on the hydrocarbon accumulation of deep carbonate rocks. The results show that: (1) The two key unconformities of the Tongwan and Caledonian periods were primarily developed in deep carbonate rocks. Firstly, Tongwan's unconformities are characterized by regional disconformities between the second and third members of the Dengying Formation, the top formation of the Sinian and the lower Cambrian, strips of which zigzag through the north and south sides of the study area. Secondly, the Caledonian unconformity is characterized by a regional unconformable contact between the lower Permian and the ower Paleozoic strata. From NE to SW, the age of the strata, which were subject to erosion, changes from new to old, the denudation distribution showing as a nose‐shaped structure which inclines towards the ENE. (2) Boundary fault and transtensional strike‐slip faults developed in the Sinian to Paleozoic strata. In profile, there are three types of structural styles: steep and erect, flower structures, 'Y' and reversed 'Y' type faults. In plane view, the Sinian developed extensional boundary faults extending in an almost NS direction, strike‐slip faults developing and extending linearly in approximately EW, WNW and NE strikes in the Cambrian, with characteristically more in the south and less in the north. (3) The faults in the northern slope show obvious zonal deformations in transverse view as well as significant stages and stratified activity in a longitudinal direction. Among them, the activity of faults in the Sinian was the strongest, followed by the activity in the Cambrian period, the activity intensity of faults in the Permian period being the weakest. This fault activity can be divided into four periods: Sinian, Cambrian‐Permian, the early Indosinian period and the late Indosinian‐Himalayan period, the transtensional strike‐slip faults being the products of oblique extensions of pre‐existing weak zones in the Xingkai and Emei taphrogenesis, with a particular inheritance in the main faults. (4) Combined with hydrocarbon accumulation factors, it is considered that the epigenetic karstification of the Tongwan and Caledonian unconformities in the northern slope controlled the formation and distribution of carbonate karst reservoirs over a large area, also acting as a good pathway for oil and gas migration. The extensional faults developed at the margin of the NS trending rift, controlling the sag‐platform sedimentary pattern in the Dengying Formation of the Sinian. Strike‐slip faults in NE, WNW and ENE directions may control the micro‐geomorphological pattern inside the platform and intensify the differential distribution of grain beach facies. The multi‐stage hereditary activity of strike‐slip faults not only improved the porosity and permeability of the reservoirs, but also acted as the main channel of oil and gas migration, providing favorable conditions for the development of the current multi‐layer gas‐bearing scenario in the northern slope of the Central Sichuan Basin. [ABSTRACT FROM AUTHOR]

To understand the origin of curved subduction zones has been one of the major challenges in plate tectonics. The Mongol-Okhotsk Orogen in Central Asia is characterized by the development of a U-shaped oroclinal structure that was accompanied by the continuous subduction of the Mongol-Okhotsk oceanic plate. Therefore, it provides a natural laboratory to understand why and how a subduction system became tightly curved. In this study, we provide the first structural observation around the hinge of the Mongolian Orocline (the Zag zone in Central Mongolia), with an aim to constrain the oroclinal geometry and to link hinge zone structures with the origin of the orocline. Our results show that rocks in the Zag zone are characterized by the occurrence of a penetrative foliation that is commonly subparallel to bedding. Both bedding and dominant fabric in the Zag zone are steeply dipping, and their strike orientations in a map view follow a simple curve around the hinge of the Mongolian Orocline, thus providing the first structural constraint for 3D geometry of the orocline. A secondary penetrative fabric parallel to the axial plane of the orocline was not observed, indicating a low degree of orogen-parallel shortening during oroclinal bending. Combining with available geological and geophysical data, we conclude that the Mongolian Orocline was developed in a period of Permian to Jurassic, and its origin was linked to the subduction of the Mongol-Okhotsk oceanic slab. We consider that the low-strain oroclinal bending likely resulted from the along-strike variation in trench retreat, which was either triggered by the negative buoyancy of the Mongol-Okhotsk oceanic slab, or driven by the relative rotation of the Siberian and North China cratons. Our results shed a light on 3D geometry and geodynamic mechanisms of large-scale oroclinal bending in an accretionary orogen. [ABSTRACT FROM AUTHOR]

In recent years, significant breakthroughs have been achieved in shale gas exploration and exploitation of marine and continental shales in petroliferous basins of China. As an important petroliferous basin in China, marine–terrestrial transitional shale was widely distributed among the Southern North China Basin (SNCB). However, biomarkers distribution characteristics of marine–terrestrial transitional shale in the SNCB, which can reveal the organic matter inputs and paleoenvironmental characteristics, is not widely concerned. In general, organic matter in a transitional environment can be affected by the amounts of organic matters input from fresh water and aquatic organisms from the sea. To systematically investigate the organic geochemical characteristics of biomarkers in marine–terrestrial transitional shale from SNCB, core samples from the Upper Shihezi, Shanxi and Taiyuan formations were obtained from a single borehole in the SNCB. Gas chromatography–mass spectrometry (GC–MS) analysis was conducted on the saturated hydrocarbons. n‐Alkanes, acyclic isoprenoid alkanes, terpanes, and steranes were detected to study the change in organic matter inputs and sedimentary paleoenvironment of the marine–terrestrial transitional shale. The results reveal that organic matter inputs obviously changed during the sedimentary period in the study area of the SNCB. In addition, the terrestrial higher plants contributed more organic matter to shale from the Upper Shihezi Formation compared to the Taiyuan Formation and the Shanxi Formation. The shift of organic matter inputs is consistent with marine regression in the Early Permian period, which may significantly influence the organic matter input characteristics. Meanwhile, the marine–terrestrial transitional shale, including samples from the Taiyuan, Shanxi and Upper Shihezi formations, was deposited in a relatively oxic condition during the depositional process. [ABSTRACT FROM AUTHOR]

The Central Asian Orogenic Belt (CAOB) is one of the huge accretionary orogenic belts on the earth. NE China in the eastern segment of CAOB consists of several blocks connected by the accretionary belts and suture zones. The subduction and accretion of the Paleo-Asian Ocean (PAO) during the late Paleozoic around the Jiamusi Block and Zhangguangcailing Terrane (ZGCT) has been a subject of debate in terms of location, polarity, and timing. Our study found that the western margin of the ZGCT developed Early Carboniferous felsic magmatism with ages of 356–334 Ma newly obtained by LA–ICP–MS zircon U Pb dating. These igneous rocks, including strongly peraluminous rhyolites and I-type granites and rhyolites, display geochemical characteristics of medium- to high-K calc-alkaline series, and most of them have positive ε Hf (t) values, indicating an active continental margin setting. On the other hand, the Early Carboniferous magmatism was absent in the Jiamusi Block. Therefore, we suggest there existed a branch of the PAO that extended north-south along the western margin of the ZGCT. The magmatism in the western margin of the ZGCT migrated eastward to the western Jiamusi Block during the Carboniferous, accompanied by an increase in the depth of magma source, indicating an eastward advancing subduction of the PAO. The latest Carboniferous–earliest Permian marked a period of tectonic regime transition, during which the eastward-subducting plate along the western margin of the ZGCT began to roll back, resulting in the formation of bimodal volcanic rocks and A-type rhyolites across the ZGCT with a slight westward younging trend. Simultaneously, the eastern margin of the Jiamusi Block started to be controlled by the westward advancing subduction of the Panthalassa plate. • A newly found Early Carboniferous magmatic arc in western Zhangguangcailing Terrane. • There developed an eastward subduction along the western Zhangguangcailing • Terrane. • Zhangguangcailing Terrane was the western margin of Jiamusi Block in late Paleozoic. [ABSTRACT FROM AUTHOR]

The Late Carboniferous–Early Permian period is a significant transitional phase within the late Paleozoic ice age and to investigate the sedimentary–tectonic evolution of the Qaidam Basin in this period is crucial for comprehensively understanding the tectonic history of the northeastern Paleo-Tethys Ocean and the related response to energy and mineral resources. This paper focuses on the Carboniferous–Permian strata of the Wanggaxiu-Dongdagou outcrop that was taken to represent the southern Oulongbruk terrane in the eastern Qaidam Basin. We determined the ages of tuff interbeds within the Zhabusagaxiu Formation originally identified as the upper Carboniferous and obtained the crystallization age spectra of detrital zircon grains from Carboniferous to lower Permian sandstones using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) isotope geochemical techniques. The origin of the volcanic ash and the sedimentary–tectonic evolution in this period were analyzed. The results indicate that the original Zhabusagaxiu Formation can be divided into two chronostratigraphic units: the upper Carboniferous Zhabusagaxiu Formation and the lower Permian. The earliest age obtained from tuffaceous layers within the dark shale interval is 297.8 ± 3.0 Ma (mean square weighted deviation (MSWD) = 0.87), which suggests a stratigraphic boundary between the Carboniferous and Permian periods. Detrital zircons from Carboniferous–Permian samples in the southern Oulongbruk terrane predominantly originated from the Qaidam block-North Qaidam ultrahigh-pressure belt continental island arc to the south. The ultrahigh-pressure belt had a significantly increased contribution to the detrital source supply system from the Late Carboniferous to Early Permian, while the Qaidam block experienced frequent volcanic eruptions from 298 to 293 Ma, dispersing volcanic ash only northward to the Oulongbruk back-arc basin and the Zongwulong Trough. The upper Carboniferous Zhabusagaxiu Formation was marked by siliceous clastic rock–carbonate rock interbedding in an epicontinental sea, while the lower Permian was characterized by shallow to bathyal marine shelf to subaqueous sedimentation. The Early Permian transgression potentially represents the largest transgression during the late Paleozoic ice age, indicating an enriched hydrocarbon-generating interval. • C/P boundary in the Qaidam Basin was determined an age of 297.8 士 3.0 Ma. Carboniferous-Permian boundary in the Qaidam Basin has been determined an oldest age of 297.8 ± 3.0 Ma. • The Qaidam block experienced frequent volcanic eruptions from 298 to 293 Ma. • Earliest Permian volcanic ashes dispersed northward farthest into the Zongwulong trough. • Prograding sequence in the lower Permian represents the most significant marine transgression during the late Paleozoic ice age. [ABSTRACT FROM AUTHOR]

[Display omitted] • Calcic minerals in skarns constrain distinct mineralizing stages and fluid evolution. • Garnet zoning in skarns reflects fluid dynamics, chemistry, temperature, and redox conditions, while the REE features result from surface adsorption and crystal chemistry substitutions. • Garnet U-Pb age and associated mineral assemblages source constraints as well as the distribution of skarn minerals and correlations between metal elements and andradite have exploration implications. The Mount Garnet Zinc deposit in NE Queensland, Australia, is located in the region of voluminous magmatism associated with the formation of Palaeozoic continental arcs of Gondwana. Ore-forming events of this deposit are related to the intrusion of the Kennedy Igneous Association (KIA) – a large suite of igneous rocks spanning Late Carboniferous to Early Permian in age – into the Silurian limestone (Chillagoe Formation) in the Hodgkinson Province (Mossman Orogen). Petrographic observations and in situ major and trace element analysis reveal the sequence of garnet growth and fluid-rock interaction during skarn formation. Three types of garnets are identified, Grt I (including IA and IB) and Grt II. Grt IB is related to Zn-Pb mineralization. All garnets have elevated Sn and W and the highest levels of W and Sn are observed in Grt II. Garnet U-Pb ages of Grt IB provide the first direct geochronological result of hydrothermal minerals in the Mount Garnet region. New data argues that the base metal mineralization may take place during early Permian period and be sourced from the Claret Creek Supersuite. Sn-W mineralization may be associated with the O'Briens Creek Supersuite. [ABSTRACT FROM AUTHOR]

The early Permian basalts of the Tarim Basin of NW China are geographically widespread, covering over 200,000 km2 and are in places up to 1‐km thick and hence frequently referred to represent a Large Igneous Province (LIP). Available volume estimates are based on average lava thickness multiplied by area, using these values results in volumes exceeding 100,000 km3, and is commonly cited as being evidence of LIP status. Using a database of 58 boreholes, field sections, and seismic data we calculate a range of basalt isopach maps, and use these to estimate new, more refined overall eruption volumes. These volumes are significantly smaller than previously reported estimates. We demonstrate that the thickness distribution of erupted basalts is nonuniform and strongly skewed, indicating that volume estimates using an arithmetically averaged thickness of input data will result in overestimation of total volumes. We find that even with the addition of an estimated nonerupted volume component, representing cumulates and intrusions, that the total volume of the Tarim volcanics is significantly below the minimum threshold of a LIP. Using a simple Monte Carlo model we demonstrate that even while accounting for uncertainty and error in the input data, the probability of the total volume exceeding 100,000 km3 is very low. The new volume estimates imply a revision of the climate and environmental impact of the Tarim volcanism. We therefore suggest that the term Tarim Igneous Province should be used instead of Tarim Large Igneous Province. Plain Language Summary: The early Permian (287–267 million years ago) basaltic rocks of the Tarim Basin in Northwestern China are geographically widespread, and can be up to 1 km in thickness. This has led to the hypothesis that these rocks represent a period of significantly voluminous igneous activity across the area, in what is known as a Large Igneous Province (LIP). LIP are defined by a set of criteria including area, volume, and a short‐duration of emplacement. In this study, we have collated all available data to test whether the basalts within the Tarim Basin meet the minimum criteria to be classified as a LIP. In this study, we demonstrate that when integrating a large number of geographically widespread boreholes and outcrops, regional seismic data and published age data that the Tarim basalts represent a significant period of igneous activity, but do not meet the threshold of a LIP. This finding is important as the volume of igneous rock formed during periods of intense igneous activity is used in geological and climate models to infer past climatic effects and extinctions. We also demonstrate that relatively simple calculations of the volume of LIPs will typically overestimate their volume and thus environmental impact, and therefore suggest that all future studies of this nature should aim to integrate all available data and consider uncertainty and probability when estimating eruption volumes. Key Points: We estimate the erupted and total igneous volume of the upper Permian Tarim basaltsCalculated volumes are below the minimum definition of a Large Igneous Province (LIP) and we suggest the use of the term Tarim Igneous ProvinceWhen estimating LIP volumes, average thickness multiplied by area leads to overestimates of volume and should not be used [ABSTRACT FROM AUTHOR]

Gigantopterid plants share common traits of megaphyllous leaves with multi-ordered venation and have a stratigraphic distribution restricted to the Permian Period. They display a large variety of leaf morphologies which may indicate affinities from more than one plant groups including ferns and pteridosperms such as the peltasperms. Here we describe a new genus of gigantopterid with two species from the upper Permian Nayixiong Formation in the Daha Coalfield, Qinghai Province, China. The new genus Filigigantopteris is markedly different from other gigantopterid genera in having fern-like leaf architecture with double-meshed venation. Filigigantopteris asymmetrica gen. et sp. nov. is characterised by its asymmetric pinnules with dissected lobes, while Filigigantopteris dahaia gen. et sp. nov. is characterised by its once-pinnate frond. A gigantopterid leaf figured from the Lopingian of southwest China that was previously incorrectly assigned to Gigantopteris nicotianaefolia may represent a third species of Filigigantopteris. The new genus further emphasises the morphological diversity and obscure systematic position of the Permian gigantopterids. In addition, three types of functional feeding groups, including hole feeding, margin feeding and probably skeletonisation, are present on laminae of Filigigantopteris, suggesting frequent and diverse plant-insect interactions between gigantopterid megaphylls and herbivorous insects in Cathaysia. [ABSTRACT FROM AUTHOR]

Horseshoe crabs within Austrolimulidae represent the extreme limits to which the xiphosurid Bauplan could be modified. Recent interest in this group has uncovered an unprecedented diversity of these odd-ball xiphosurids and led to suggestions that Austrolimulidae arose during the Permian Period and had become extinct by the end of the Triassic Period. Here, we extend the temporal record of Austrolimulidae by documenting a new horseshoe crab from the Lower Jurassic (Hettangian) Bayreuth Formation, Franconiolimulus pochankei gen. et sp. nov. The novel specimen displays hypertrophied genal spines, a key feature indicative of Austrolimulidae, but does not show as prominent accentuation or reduction of other exoskeletal sections. In considering the interesting family, we explore the possible origins and explanations for the bizarre morphologies exhibited by the Austrolimulidae and present hypotheses regarding the extinction of the group. Further examination of horseshoe crab fossils with unique features will undoubtedly continue to increase the diversity and disparity of these curious xiphosurids. [ABSTRACT FROM AUTHOR]

During the Permian period of the southern China North Plate, a layer of marine mudstone (source rock) with oil and gas potential has been widely deposited, with a thickness of about 10.4 m, but their formation mechanism remains unclear. Here, through the application of various analysis techniques, the mineral composition of the mudstone and a series of related geochemical data are obtained to investigate their sedimentary environment and tectonic setting. Mineral composition analysis describes that marine mudstone is mainly composed of quartz, illite, kaolinite, montmorillonite, and other silicate minerals, while carbonate components such as calcite are rare. Meanwhile, the higher content of clay minerals promoted the organic matter during the deposition period enrichment. Indicators and diagrams (i.e., chemical index of alteration [CIA] [> 80], index of compositional variability [ICV] [~ 0.6], A‐CN‐K, Th/Sr vs. Zr/Sr) reveal that marine mudstone was deposited for the first time under strong weathering. Some trace element ratios and redox elements provide evidence that in warm and arid climates, mudstones are deposited under oxic‐anoxic conditions based on the participation of seawater, which is consistent with the conclusion of palaeomagnetics. The binary discriminant diagrams of Al2O3 versus TiO2, Hf‐La/Th versus Ni‐TiO2 suggest that the marine mudstone parent rock is felsic igneous rock, and the lithology may be granite. Combining the regional structural evolution and the direction of transgression during the sedimentary period, it is speculated that the provenance of marine mudstone is the North Qinling tectonic belt in the southwest of the study area and the Yinshan ancient land in the north. [ABSTRACT FROM AUTHOR]

The northern Alxa orogenic belt, located in the middle segment of the Central Asian Orogenic Belt, is a junction between the North China Craton, Tarim Craton and Mongolian microcontinents. However, its Permo-Carboniferous tectono-palaeogeographic evolution has not been well established. In this study, new zircon U–Pb–Hf isotopic data for the Permo-Carboniferous clastic rocks were used to address the above issue. Based on our dating work and fossil assemblages, we confirmed that the Amushan, Maihanhada, Aqide and Haersuhai formations were formed in the late Carboniferous to early Permian, early to middle Permian, middle Permian and late Permian periods, respectively. The Amushan Formation sandstone in the Zhusileng area contains abundant Palaeozoic zircons (with age peaks at 440 Ma, 475 Ma and 539 Ma) and some Precambrian zircons. These zircon ages and the southeast transgressive direction suggest the provenance to be the local Zhusileng–Hangwula block and the nearby Yagan continental margin. The zircon age pattern with a high proportion of detrital zircons much older than the depositional time and no detrital zircons close to the depositional time suggest an extensional basin depositional setting. The clastic rocks of the Maihanhada, Aqide and Haersuhai formations inherited the source for the Amushan Formation, with a greatly increased input of Permo-Carboniferous volcanic rocks with post-collision or intraplate chemical affinity. Accordingly, a Permo-Carboniferous extensional stage was suggested. Finally, a tectono-palaeogeographic model was reconstructed for the northern Alxa orogenic belt, evolving from a late Carboniferous transgression with crustal extension to early to middle Permian rapid basin filling and a late Permian marine regression. [ABSTRACT FROM AUTHOR]

The Kamusite pluton is located in the eastern Junggar area, the westernmost segment of the Karamaili structural belt, and is predominantly composed of medium granite and microgranite with an exposure area of 30 km2. The U–Pb zircon geochronology of the Kamusite granites indicates that they crystallized in the late Carboniferous period (328–321 Ma). These granites exhibit high contents of SiO2 (76.09–77.85 wt %) and K2O + Na2O (8.01–9.06 wt %), but low MgO (0.01–0.14 wt %), CaO (0.07–0.32 wt %) and TiO2 (0.01–0.13 wt %) contents, showing alkalic–calcic, weakly peraluminous and ferroan features. They are depleted in Ba, Sr, Ti and P and enriched in Rb and some high-field-strength elements (Hf, Nd, Ta and Y); their rare earth element patterns are slightly right-leaning with strongly negative Eu anomalies, high 10 000 * Ga/Al (3.4–5.36, >2.6) and especially high Y/Nb ratios (1.61–10.33, >1.2), showing the geochemical characteristics of A2-type granite. These granites were produced by partial melting in a high-temperature, low-pressure, reduced and anhydrous environment and experienced extensive fractional crystallization, which concomitantly resulted in tin mineralization. Combining the high positive zircon ϵHf(t) values of +10.9 to +15.76 with young Hf (TDM2) model ages (638–330 Ma), it can be suggested that underplating-related mantle-derived materials were the original source of the Kamusite A2-type granites; namely, these granites formed by the partial melting of juvenile crust. The record of large-scale magmatism indicates that the whole tectonic belt was in a postcollisional extensional setting induced by staged delamination from west to east during the late Carboniferous to early Permian periods. [ABSTRACT FROM AUTHOR]

The calibration of sedimentary rock absolute dates is one of the difficulties in sedimentological and stratigraphic research. Since strontium (Sr) resides in seawater much longer (≈106 a) than the seawater intermixing time (≈103 a), the Sr isotopic composition of global seawater is uniform at any time and results in a stable system throughout geological history, based on which a global Sr isotope composition dating database has been established for age‐calibration of marine strata. The Permian stratigraphic sections in the northern part of the Upper Yangtze block, southern China, record continuous marine sediments with clear stratigraphic boundaries and is suitable for stratigraphic dating of Sr isotopes. Based on sampling and Sr isotopic compositions of Permian carbonate strata in the northern part of the Upper Yangtze, a Permian Sr isotope evolution curve was established. According to the basic principles of Sr isotope stratigraphy, the global Strontium isotope age database can be used to calibrate the Permian stratigraphic dates in the northern Upper Yangtze. The results show that the Sr isotope evolution curves for the marine carbonate rocks in the Permian stratigraphic section of the Upper Yangtze present a decreasing trend from the mid‐Qixia stage (P2) to the mid‐Wujiaping stage (P3), and then rise from the middle Wujiaping stage to the end of Changxing stage (P3). When the Permian Sr‐isotope evolution curve is compared with the global Sr isotope evolution curve in the northern Upper Yangtze, the two are consistent in their long‐term evolutionary trend, indicating that Permian global geological events are important controlling factors for the composition and evolution of Sr isotopes. The 87Sr/86Sr value decreased gradually in the background of large‐scale regressions at the turn of middle to late Permian period, revealing that the Emeishan basalt eruption occurred near the Maokou/Wujiaping boundary (GLB). Sr‐isotope stratigraphy dating was performed on the boundaries of the Qixia Formation/Maokou Formation, Maokou Formation/Wujiaping Formation (GLB), Wujiaping Formation/Changxing Formation (WCB) and the Permian/Triassic (PTB) using the Global Strontium Isotope Age Database. The results are 270.4 Ma, 261.2 Ma, 254.5 Ma and 249.7 Ma, respectively. Based on this, the eruption age of the Emeishan basalts is defined at about 261.2 Ma., which is more coincident with that acquired from other previous dating methods on the eruption age of the Emeishan basalts, and therefore proves that the application of Sr isotopic stratigraphy to dating marine sedimentary units is an effective method. [ABSTRACT FROM AUTHOR]

The radiogenic strontium isotope (87Sr/86Sr) system is a powerful tool for constraining sea‐level change and palaeoclimatic variations as well as tectonic activities. The Permian is a period that records the lowest seawater Sr‐isotopic ratios in the Earth's history. The near‐primary geochemical signatures retained in the micritic carbonates of the Luduba section (uppermost lower to Middle Permian) on the northern margin of the South China Block allowed the reconstruction of reliable carbon and Sr‐isotope profiles for global chemostratigraphic correlations. The investigated interval (~300 m) spans the Chihsia and overlying Maokou formations (Kungurian to Capitanian series). The 87Sr/86Sr values decrease consistently upward from 0.70833 to 0.70684, and their trend correlates well with a long‐term increase in the carbon isotope (δ13C) values. The negative correlation between the 87Sr/86Sr and δ13C values suggests that the sea‐level change, climatic conditions, opening of the Neo‐Tethys Ocean, and accretion of the Pangean Supercontinent are among the factors that might have contributed to the consistent depletion of the 87Sr/86Sr values. The rate of upward decrease in 87Sr/86Sr values throughout the Chihsia Formation is generally higher than that of the overlying Maokou Formation, which provides a possible marker for intra‐ and interbasinal basin stratigraphic correlations. The general increase in the δ13C values of the Luduba profile peaks at ~5‰, which correlates with the distinct lowest 87Sr/86Sr value (~0.70684) near the top of the Maokou Formation (Upper Capitanian). The δ13C values decrease to 3.6‰ at the top of the Maokou Formation, that correlates with the rapid sea‐level drop in the Late Guadaualupian worldwide. Meanwhile, the87Sr/86Sr ratios remain low values, probably due to the development of cold climate, increasing input of hydrothermal flux and low terrestrial runoff. [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 Devonian marked a significant phase in the evolutionary history of the Brachiopoda. During this period, the Phylum achieved its peak diversity (Emsian) and suffered one of its greatest declines (Frasnian–Famennian), ranking second only to the mass extinction event at the Late Permian period. In Brazil, the Amazonas Basin has a rich record of Devonian brachiopods distributed in four stratigraphic units: i) Manacapuru (Lochkovian), ii) Maecuru (early Eifelian), iii) Ererê (late Eifelian), and iv) Barreirinha (early Frasnian) formations. This article aims to survey the occurrences of brachiopods during the Devonian in the Amazonas Basin and to discuss the possible factors that influenced their diversity. Environmental changes may explain the variation of brachiopod diversity throughout the Devonian in the Amazonas Basin. We noted that the diversity variation of Devonian brachiopods in the Amazonas Basin unfolded in three distinct stages. The peak of brachiopod diversity occurred in the early Eifelian (Maecuru Formation), when the Amazonas Basin was between the subtropical latitudes 30°S and 60°S, under shallow marine and cold conditions, justified by the absence of carbonates, evaporites, and reefs in the region (Stage 1). The first diversity decline is recorded in the Ererê Formation (late Eifelian), attributed to a warmer climate and deeper water than in the Maecuru Formation (Stage 2). During the Frasnian, there was a second diversity decline of brachiopods in the Amazonas Basin (Barreirinha Formation). A major global transgression occurred in the Late Devonian. In this period, the Amazonas basin experienced the deepest marine conditions in its history. The brachiopods of the Barreirinha Formation occur in layers of black shale (offshore), attributed to an anoxic or dysoxic environment of high stress, which explains the low diversity of brachiopods in this unit (Stage 3). • The variation of genera of brachiopods during the Devonian in the Amazonas Basin comprises three distinct stages. • The peak of brachiopod diversity occurred in the Eifelian, when the Amazonas Basin was between the subtropical latitudes 30°S and 60°S, under shallow marine conditions, and the global ocean temperature exceeded 22 °C. • The first diversity decline is recorded in the Ererê Formation, when there was a relative rise in sea level reaching deeper waters, and the ocean temperature had a slight cooling compared to the time deposition of the Maecuru Formation. • The fauna of the Barreirinha Formation records the second decline. The brachiopods from the Barreirinha Formation occur in layers of black shale with anoxic conditions and high stress attributed to an offshore environment. [ABSTRACT FROM AUTHOR]

Volcanic ash deposits are commonly associated with shale oil enrichment worldwide, and their composition potentially playing a significant role in the origin of organic-rich shale and shale oil exploration potential. Volcanic activity occurred frequently during the depositional period of the Permian Lucaogou Formation in the Jimsar Sag, Junggar Basin. Microscopic examination shows the development of volcanic ash in the strata, but alteration of volcanic ash may affect the volcanic ash content recovered by the microscopic identification method. Through analyzing 49 rock samples, semi-quantitative restoration of volcanic ash content was conducted combined using Hg, major elements, strontium isotopes and thin section analysis. The restored volcanic ash content, measured via Hg and elemental methods, represents the stratigraphic unit's weight percentage, while the microscopic identification method denotes the stratigraphic unit's volume percentage. Although they are different ratios, they exhibit good correlation. Research suggests that volcanic ash is commonly present in the Lucaogou Formation of the Jimsar Sag. The volcanic ash content varies greatly, from 11% to 96%, mainly within the 10%–40% range. Only a few samples exhibited volcanic ash content exceeding 60%. The nutrients brought by the volcanic ash promoted organic productivity. This, in turn, increased the organic matter content in the water column and facilitated the formation of a reducing environment. The abundance and type of organic matter are crucial factors in determining the potential for shale oil. Thus, volcanic ash influences the enrichment of organic matter and the shale oil potential of the Lucaogou Formation. • Semi-quantitative restoration of volcanic ash content was conducted in the Lucaogou Formation. • Multiple methods were combined to restore volcanic ash content, rather than just through microscopic observation. • The original volcanic ash content includes unaltered volcanic ash and altered minerals. Minerals formed by volcanic ash alteration were taken into account when recovering volcanic ash content. • Environmental changes may affect the enrichment of Hg. The effects of chemical weathering degree and redox conditions on Hg enrichment were considered. [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]

The organic-rich shale of the Upper Carboniferous-Lower Permian transition period in the eastern margin of the Ordos Basin, China, was formed in a marine-continental facies sedimentary environment. With a high content of total organic carbon (TOC) and a large cumulative thickness, it is considered a good source rock for shale gas development. The sedimentary environment of marine-continental transitional shale is obviously different from that of marine shale, which leads to different enrichment characteristics of organic matter. In this paper, shale samples were collected from XX# well of the Taiyuan and Shanxi Formations across the Upper Carboniferous-Lower Permian, which is typical marine-continental transitional shale. The TOC, major elements, and trace elements were measured, and the formation and preservation conditions were investigated using multiple geochemical proxies, including paleoclimate, redox parameters, paleoproductivity, and controls on the accumulation of organic matter. The TOC of Shanxi Formation is higher than that of Taiyuan Formation. In the Taiyuan Formation, TOC is positively related to the redox index (V, U, and V/Cr), indicating that the dysoxic bottom water environment is the key factor controlling organic matter accumulation. For Shanxi Formation, there is a positive correlation between TOC and paleoclimate, which indicates that the enrichment of organic matter is affected by warm and humid paleoclimate and oxic environment. In addition, the paleoproductivity is lower with a positive correlation with TOC for the marine-continental transitional organic-rich shale, suggesting that it was inferior to the gathering of organic matter. [ABSTRACT FROM AUTHOR]

Magmatic rocks from the Dolomites, Carnic and Julian Alps, Italy, have been sampled to investigate the origin and geodynamic setting of Triassic magmatism in the Southern Alps. Basaltic, gabbroic and lamprophyric samples have been characterized for their petrography, mineral chemistry, whole-rock major and trace elements, and Sr, Nd and Pb isotopic compositions. Geothermobarometric estimates suggest that the basaltic magmas crystallized mostly at depths of 14–20 km. Isotopic data show variable degrees of crustal contamination decreasing westwards, probably reflecting a progressively more restitic nature of the crust, which has been variably affected by melting during the Permian period. Geochemical and isotopic data suggest that the mantle source was metasomatized by slab-derived fluids. In agreement with previous studies and based on geological evidence, we argue that this metasomatism was not contemporaneous with the Ladinian–Carnian magmatism but was related to previous subduction episodes. The lamprophyres, which likely originated some 20 Ma later by lower degrees of melting and at higher pressures with respect to the basaltic suite, suggest that the mantle source regions of Triassic magmatism in the Dolomites was both laterally and vertically heterogeneous. We conclude that the orogenic signatures of the magmas do not imply any coeval subduction in the surrounding of Adria. We rather suggest that this magmatism is related to the Triassic rifting episodes that affected the western Mediterranean region and that were ultimately connected to the rifting events that caused the break-up of Pangea during the Late Triassic – Early Jurassic period. [ABSTRACT FROM AUTHOR]

New details of chemical structure of Araucaria lignin are the focus of this paper, since Araucaria is a relict plant which fossils are dated by the Permian period. Quantitative chemical analysis, FTIR, EPR and 2D NMR spectroscopies, Py-GC/MS and nitrobenzene oxidation have been used to characterize the Araucaria lignin. This work highlighted the structural features of the lignin of Araucaria , which distinguish it from modern coniferous (gymnosperm) lignins. This lignin exhibits pronounced paramagnetic properties with the concentration of paramagnetic centers of 3.0 × 1017 spin/g, the value of g-factor of 2.0036 corresponds to the phenoxyl radical. The Araucaria lignin is apparently unique since it does not belong to the known G, GS or GSH types. For the first time it was quantitatively proven that he lignin of Araucaria was assigned to compositionally heterogeneous GH lignins, which is not typical for modern lignins. [ABSTRACT FROM AUTHOR]

The analysis of the history of the development and formation of the Pre-Caspian basin, the characteristics of the main stages of development from the Middle Devonian to the Lower Permian (Artinsky and Kungurian stages) are given. The main tectonic elements are identified, the analysis of which is used to assess the internal structure and prospects of oil and gas potential of the Paleozoic sediments. Separate analysis of sedimentation conditions and paleotectonic reconstructions along the northern, eastern, and southern pre-bead part of the Pre-Caspian basin was performed. Local structures and zones that are of exploratory interest in relation to the prospects of oil and gas potential are identified. Separately, an assessment and forecast of the conditions for the formation of the central regions of the deep Pre-Caspian basin are given. [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]