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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 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]

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 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]

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 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]

Dicynodontia is a major clade of terrestrial tetrapods that greatly diversified during the Permian and Triassic periods, reaching a worldwide distribution. In this study, the endocranial cavity of the Brazilian Permian dicynodont Rastodon procurvidens is described based on a digital endocast obtained using digital imaging (X‐ray computed tomography) and 3D modeling. It was possible to reconstruct the brain, olfactory bulbs, inner ear, some neurovascular canals, cranial nerves, the nasal cavity, and the maxillary recesses. The endocast of R. procurvidens preserves a typical plesiomorphic morphology of non‐mammaliaform therapsids, being predominantly tubular and displaying a relatively short and robust hindbrain. Encephalization quotients (EQs) were calculated for R. procurvidens, resulting in EQs of 0.09 ± 0.03 and 0.13 ± 0.05 (Jerison's EQ and Manger's EQ, respectively). Finally, some biological implications of the endocast morphology were inferred for R. procurvidens. Its inner ear is especially small, and its orientation implies a slightly downturned head posture in life. Furthermore, the presence of uncompressed maxillary recesses in R. procurvidens indicates a correlation between the enlargement of the recesses and the reduction of the tusks, also seen in other dicynodonts with reduced tusks. [ABSTRACT FROM AUTHOR]

The Zunyi manganese deposits, which formed during the Middle to Late Permian period and are located in northern Guizhou and adjacent areas, are the core area of a series of large‐medium scale manganese enrichment minerogenesis in the southern margin and interior of the Yangtze platform, Southern China. This study reports the universal enrichment of rare earth elements (REEs) in Zunyi manganese deposits and examines the enrichment characteristics, metallogenic environment and genesis of REEs. The manganese ore bodies present stratiform or stratoid in shape, hosted in the silicon–mud–limestones of the Late Permian Maokou Formation. The manganese ores generally present lamellar, massive, banded and brecciated structures, and mainly consist of rhodochrosite, ropperite, tetalite, capillitite, as well as contains paragenetic gangue minerals including pyrite, chalcopyrite, rutile, barite, tuffaceous clay rock, etc. The manganese ores have higher ΣREE contents range from 158 to 1138.9 ppm (average 509.54 ppm). In addition, the ΣREE contents of tuffaceous clay rock in ore beds vary from 1032.2 to 1824.5 ppm (average 1396.42 ppm). The REEs from manganese deposits are characterized by La, Ce, Nd and Y enriched, and existing in the form of independent minerals (e.g., monazite and xenotime), indicating Zunyi manganese deposits enriched in light rare earth elements (LREE). The Ceanom ratios (average –0.13) and lithofacies and paleogeography characteristics indicate that Zunyi manganese deposits were formed in a weak oxidation‐reduction environment. The (La/Yb)ch, Y/Ho, (La/Nd)N, (Dy/Yb)N, Ce/Ce* and Eu/Eu* values of samples from the Zunyi manganese deposits are 5.53–56.92, 18–39, 1.42–3.15, 0.55–2.20, 0.21–1.76 and 0.48–0.86, respectively, indicating a hydrothermal origin for the manganese mineralization and REEs enrichment. The (δ13CV‐PDB (−0.54 to −18.1%) and (δ18OSMOW (21.6 to 26.0%) characteristics of manganese ores reveal a mixed source of magmatic and organic matter. Moreover, the manganese ore, tuffaceous clay rock and Emeishan basalt have extremely similar REE fractionation characteristic, suggesting REEs enrichment and manganese mineralization have been mainly origin from hydrothermal fluids. [ABSTRACT FROM AUTHOR]

Detrital age relationship between major lithounits of the orogeny and foreland basin strata can elucidate orogenic events. However, analyses of some selected samples of a certain time interval from a sedimentary basin can lead to misjudgement. We present detrital zircon U–Pb age analyses of some older sedimentary strata of the Tansen Group, a renowned basin for the explanation of the Himalayan Orogeny. Sandstone and tuff samples of the Permian and Cretaceous Periods from the Gondwana sequence of the Lesser Himalaya of eastern Nepal and western Nepal were subjected to U–Pb age analyses, and the results were compared with available younger strata of the same basin along with the major lithotectonic units of the Himalaya. The detrital zircon age population of different units enables us to propose a new stratigraphic framework for the eastern Nepal Gondwana sequence and correlate them with the well‐established Gondwana sequence of the western Nepal Lesser Himalaya. This study reveals that the source region for the Gondwana sequence (Permian to Cretaceous) and post‐Gondwana sequence (Eocene to Miocene) is alternating and casts doubt upon the famous implications for the India and Asia collision and metamorphic core exhumation made from the basin analysis of these sedimentary basins of the southern part of the Himalayan Thrust Fold Belt (HTFB). Furthermore, we argue that these basins cannot be used for the reconstruction of collision and exhumation history of the Himalaya as being used. Alternatively, the results are more consistent with the possibilities of recent unconventional hypotheses of sediment contribution of the Greater Himalaya to the Permian strata of the Lesser Himalaya and the Cretaceous rifting of the Tibetan–Himalayan Microcontinent followed by the accretion of the microcontinent before collision of India and Asia. [ABSTRACT FROM AUTHOR]

The Permian global mass extinction events and the eruption of the Emeishan flood basalts in the Upper Yangtze region should display certain responses during the evolution of carbon isotope. In this paper, the Permian carbon isotopic evolution in the Upper Yangtze region is examined through systematic stratotype section sampling and determination of 13C in the northern Upper‐Yangtze regions and Southern China. Additionally, the carbon isotopic evolution response characteristics of the geological events in the region are evaluated, comparing the sea‐level changes in the Upper Yangtze region and the global sea‐level change curves. Results of this study indicated that the carbon isotopic curves of the Permian in the Upper Yangtze region are characterized by higher background carbon‐isotope baseline values, with three distinct negative excursions, which are located at the Middle–Late Permian boundary and the late period and end of the Late Permian. The three distinct negative excursions provide an insightful record of the global Permian mass extinction events and the eruption of the Emeishan flood basalts in the Upper Yangtze region. The first negative excursion at the Middle–Late Permian boundary reflected the eruption of the Emeishan flood basalts, a decrease in sea level, and biological extinction events of different genera in varying degrees. The second negative excursion in the Late Permian included a decrease in sea level and large‐scale biological replacement events. The third negative excursion of the carbon isotope at the end of the Permian corresponded unusually to a rise rather than a decrease in sea level, and it revealed the largest biological mass extinction event in history. [ABSTRACT FROM AUTHOR]

Abstract: The first tunicates with a calcareous exoskeleton are reported from Late Triassic buildup‐slope deposits of the Dolomites. Although examples of this group have been known since the early 1900s from the middle–upper Permian of eastern Asia and Sicily as Khmeria, they were erroneously attributed to rugose corals. These early representatives are small, double‐valved, conical skeletons, which evolved into multi‐plated capsules with up to 35 opercula. The latter are joined along zigzag margins, which in life could probably be opened for the atrial and branchial siphons. The construction and shape of these skeletons distinguish them from plants or other invertebrate phyla, while they share several similarities with living tunicates, specifically to sessile ascidians. Apart from a soft‐bodied genus from the lower Cambrian of China, ascidians are known only from isolated spicules, which occur sporadically from the Lower Jurassic onwards. The calcareous skeleton of these Late Triassic tunicates consists of aragonitic fibres, which form spherulitic or clinogonal microstructures. It seems that the stellate aragonitic spicules of Jurassic to Recent ascidians are a vestige of Permian–Triassic ancestors, which after the Carnian lost the ability to construct compound solid skeletons but partly still retain a soft double‐valved or multi‐operculate cellulose‐like tunic. The following taxa are described as new: Order Khmeriamorpha with the genera Khmeria Mansuy and Zardinisoma gen. nov., and the following species: Khmeria stolonifera (late Permian), Khmeria minima (Late Triassic), Zardinisoma japonicum (late Permian), Z. cassianum, Z. pyriforme, Z. polyplacophorum and Z. pauciplacophorum (all Late Triassic). [ABSTRACT FROM AUTHOR]

The Pennsylvanian to lower Permian succession at Madiyi, South China, represents a nearshore mixed siliciclastic‐carbonate system characterized by cyclic sedimentation patterns along a depth gradient from continental siliciclastics to marine open platform carbonates. Various palaeokarst features related to subaerial exposure are widely distributed. Additionally, pedogenesis was pervasive. The identification of twenty‐eight sedimentary cycles grouped into five sequences allows the reconstruction of a relative sea‐level curve. The cycles represent higher frequency changes superimposed on the long‐term evolution. After the initial transgression, the sea level remained relatively low in the late Bashkirian to early Moscovian. Then, it rose stepwise until a major drop occurred in the late Moscovian. Afterwards, the sea level rose again, but marine sedimentation ceased during at least the early Kasimovian. The area was flooded in the late Kasimovian, and the sea level rose until a late Gzhelian sea‐level drop. The subsequent marine sequence contains uppermost Gzhelian to upper Asselian deposits, which are capped by lower Permian continental facies associated with a major regional regression. Shallow to deeper marine sedimentary settings recorded high‐frequency sea‐level changes throughout South China during the late Bashkirian to Asselian. The main transgression–regression cycles are clearly associated with different depositional settings during several time intervals. Furthermore, the good correlations among South China, Ukraine, and the U.S. Mid‐continent are rooted in the impact of Gondwanan glaciations on the global sedimentation patterns. However, not all changes at Madiyi are the result of glacio‐eustatic sea‐level fluctuations; some are related to the local subsidence history and the rise of the Xuefeng Uplift. [ABSTRACT FROM AUTHOR]

We performed geochronological and geochemical analyses of the A‐type granite in the Hongol area, central Inner Mongolia, to determine its age, petrogenesis and tectonic setting, which are significant for clarifying the Late Paleozoic tectonic evolution of the Xing'an Mongolian Orogenic Belt (XMOB). The rock type of the A‐type granite in the Hongol area is alkali‐feldspar granite, and it constitutes a western part of the Baiyinwula–Dongujimqin A‐type granite belt. Zircon U–Pb geochronology yields 206Pb/238U ages ranging from 293 to 286 Ma for the alkali‐feldspar granite, indicating this granitic pluton formed in the Early Permian. The alkali‐feldspar granite is high in silica (SiO2=75.13wt%–80.17wt%), aluminum (Al2O3=10.59wt%–13.17wt%) and alkali (Na2O+K2O=7.33wt%–9.11wt%), and low in MgO (0.08wt%–0.39wt%) and CaO (0.19wt%–0.70wt%). It is obviously enriched in LILEs such as Rb, Th and K, depleted in HFSEs such as Nb, Ti, La and Ce, with pronounced negative anomalies of Nb, Ti, P, Eu, Sr and Ba. Its Sr–Nd–Pb isotopic compositions show positive εNd(t) (+0.72–+3.08), low TDM2 (805–997 Ma), and high radioactive Pb with (206Pb/204Pb)i of 18.710–19.304, (207Pb/204Pb)i of 15.557–15.604 and (208Pb/204Pb)i of 37.887–38.330. Petrological characteristics and geochemical data suggest that the alkali‐feldspar granite in the Hongol area belongs to aluminous A‐type granite. This A‐type granite formed in a post‐collisional extensional setting and was generated by the partial melting of felsic rocks in the middle‐lower crust resulting from post‐collisional slab breakoff. It is suggested that the Paleo‐Asian Ocean was closed before the Permian in central Inner Mongolia. [ABSTRACT FROM AUTHOR]

The metamorphic conditions of the Upper Permian Yangjiagou Formation in eastern Changchun, China, were evaluated based on the mineral assemblage, illite crystallinity, illite polytypism, the b dimension of illite, and the chemical composition of chlorite. The pelitic rocks in the Yangjiagou Formation are characterized by illite + kaolinite + chlorite ± mixed‐layer chlorite/smectite and detrital quartz + plagioclase. Illite in the formation has a crystallinity of 0.38–0.55 and comprises mixed 2M1 and 1Md polytypes, indicating a metamorphic temperature of >200°C. Based on the chemical composition of chlorite and the chlorite geothermometer, we estimated diagenetic to very low‐grade metamorphic conditions with temperatures of 185°C–204°C. The b dimension of illite varies from 8.992Å to 9.005Å. We used a mathematical algorithm to extend Guidotti and Sassi's (1986) diagram relating illite b dimension with temperature and pressure, and used this diagram, together with illite crystallinity and chlorite chemical composition, to semi‐quantitatively estimate the formation pressure at<1.2 kbar. These reveal that the Yangjiagou Formation has experienced very low‐grade metamorphism. [ABSTRACT FROM AUTHOR]

We report a new genus and species of Paleonisciformes–Cretolepis dongbeiensis gen. et sp. nov., from the Early Cretaceous Longjiang Formation in Qiqihar City, Heilongjiang Province. The new materials can be distinguished from other Paleonisciformes genera by possessing the following characteristics: a sclerotic ring composed of more than five small bones; three pieces of suborbitals; one dermohyomandibular; a jaw hanging apparently inclined anteriorly; long and tall horizontal branch of the preopercular, a short vertical branch, with the angle formed by the two branches slightly higher than 90°; a triangular dorsal fin in the middle point between the pelvic and anal fins. The discovery of Mesozoic Paleonisciformes in northeastern China adds to the biodiversity and geographic distribution of Paleonisciformes. [ABSTRACT FROM AUTHOR]

Abstract: Radioisotope geochronology of detrital grains coupled with quantitative classification of grain morphology can provide valuable insight into the history of sediment transportation and recycling. Here we present ca. 750 new concordant U‐Pb ages from detrital zircon grains from a relatively understudied Permian sedimentary succession in the New England Orogen (eastern Australia), coupled with values of abrasion that provides a proxy for the relative source‐to‐sink distance. We show that cumulative proportion curves for age groups that correspond to plausible source regions provide insights into the palaeodrainage, even if the basin stratigraphy is relatively poorly constrained. This approach is particularly suitable for investigating complex depositional systems that received inflow from different provenance, such as back‐arc and intra‐cratonic basins. Using the example from eastern Australia, our results show that during the Early Permian, a large regional fluvial system transported detritus from continental Gondwana across the landscape of the former active continental margin (New England Orogen) and the simultaneously developing East Australian Rift System. In addition, a local drainage system mobilised detritus within the New England Orogen. Our new constraints for the Early Permian palaeogeography support the idea that the Lower Permian successions of the southern New England Orogen were deposited in a back‐arc region that was likely linked to a retreating subduction zone. [ABSTRACT FROM AUTHOR]

Abstract: The paleogeographic reconstruction of the Variscan Mountains during late Carboniferous‐Permian post‐orogenic extension remains poorly understood, owing to the subsequent erosion and/or burial of most associated sedimentary basins during the Mesozoic. The Graissessac‐Lodève Basin (southern France) preserves a thick and exceptionally complete record of continental sedimentation spanning late Carboniferous through late Permian time. This section records the localized tectonic and paleogeographic evolution of southern France in the context of the low‐latitude Variscan Belt of Western Europe. This study presents new detrital zircon and framework mineralogy data that address the provenance of siliciclastic strata exposed in the basin. The ages and compositions of units that constitute the Montagne Noire metamorphic core complex (west of the basin) dictate the detrital zircon age populations and sandstone compositions in Permian strata, recording rapid exhumation and unroofing of the Montagne Noire dome. Cambrian‐Archean zircons and metamorphic lithic‐rich compositions record derivation from recycled detritus of the earliest Paleozoic sedimentary cover and Neoproterozoic‐early Cambrian metasedimentary Schistes X, which formerly covered the Montagne Noire dome. Ordovician zircons and subarkosic framework compositions indicate erosion of orthogneiss units that formed a large part of the dome. The youngest zircon population (320–285 Ma) reflects derivation from late Carboniferous‐early Permian granite units in the axial zone of the Montagne Noire. This population appears first in the early Permian, persists throughout the Permian section and is accompanied by sandstone compositions dominated by feldspar, polycrystalline quartz and metamorphic lithic fragments. The most recent migmatization, magmatism and deformation occurred ca. 298 ± 2 Ma, at ca. 17 km depth (based on peak metamorphic conditions). Accordingly, these new provenance data, together with zircon fission‐track thermochronology, demonstrate that exhumation of the Montagne Noire core complex was rapid (1–17 mm year−1) and early (300–285 Ma), reflecting deep‐seated uplift in the southern Massif Central during post‐orogenic extension. [ABSTRACT FROM AUTHOR]

Macro-charcoal, as direct evidence of palaeo-wildfires, is a common constituent throughout an Early Permian (Cisuralian) inertinite-rich coal seam from the Dhanpuri Coal Mine (Barakar Formation, Sohagpur Coalfield, Madhya Pradesh, India). The continuous presence of macro-charcoal within this particular seam demonstrates that fires occurred repeatedly in the source vegetation of the seam. Based on these macro-charcoal remains, an anatomical assessment of the diversity and taxonomic composition of the vegetation, which experienced wildfires and contributed to the formation of peat/coal, is provided. The vegetation that experienced regular fires was dominated by gymnosperms, with a minor component of pteridophytes. The results also support previous studies, which suggest a pyrogenic origin for the high inertinite contents of many Permian coals within Gondwana. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Shale oil exploration of the Permian Lucaogou Formation (P2l) has greatly advanced in the Jimusar Sag in the Junggar Basin. However, despite the strong exploration prospects of shale oil resources, the potential of shale oil resources in the Junggar Basin has been insufficiently assessed. This study performs systematical evaluation of P2l source rocks in the Jimusar Sag and proposes an improved hydrocarbon generation potential method to assess the hydrocarbon generation and expulsion characteristics and evaluates the shale oil resource potential of the P2l source rocks in the Jimusar Sag. The results show that the P2l source rocks are thick (up to 200 m) and are distributed over a wide area (up to 1200 km2) in the study region. It contains high TOC (2%-5%), characterized by dominantly type I and type II kerogen. The source rocks are in the low mature-mature stage, and possess good conditions for generation of hydrocarbons. The P2l source rocks reached the hydrocarbon expulsion threshold at a thermal maturity of 0.8% vitrinite reflectance. The efficiency of hydrocarbon expulsion of the source rock is 34%. The amounts of hydrocarbons generated and expelled were 65 × 108 t. Based on the above information, the shale oil resources potential is calculated to be 43 × 108 t, indicating very good shale oil resource prospect in the P2l source rocks of the Jimusar Sag. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Fusulinid fauna from the late Sakmarian-early Artinskian Khan Formation in the Kalmard area, east-central Iran, was studied using morphometric techniques to test the reliability of previous taxonomic descriptions. Fusulinids in the Kalmard area have been previously grouped into three genera ( Eoparafusulina, Perigondwania, and Neodutkevitchia) and '20 species'. Results of ordination analyses (PCA and RDA) reveal that the genera are readily distinguished, whereas only a few species previously defined within the genera Eoparafusulina and Perigondwania are recognizable. This suggests that the taxonomic descriptions and measurements for different structural elements for some of these fusulinid species are not sufficient to justify erecting separate taxonomic names. Since fusulinids are really important fauna for biostratigraphic and palaeobiogeographic interpretation in the late Palaeozic, defining species based on quantitative analysis of their morphological structures should be more accurate and improve the quality of regional correlations. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Facies models that adequately represent the diverse range of fine-grained fluvial systems are currently lacking from the literature. In this paper, the spectrum of these systems on the arid plains of western equatorial Pangea is explored, as well as the source and nature of the fine-grained sediments. Eight fluvial elements in the Early Permian Clear Fork Formation of north-central Texas represent channel systems up to 7 m deep with coarse basal deposits, three types of lateral-accretion deposits and sandstone sheets, with laminated, disrupted and massive mudstones laid down in abandoned channels and on floodplains. The three fine-grained fluvial styles represent a continuum between two end-members: sustained lateral accretion of bedload composed of quartzose sediments and mud aggregates on point bars, and oblique accretion of suspended sediment on steep accretionary benches and banks with limited lateral migration. This spectrum is controlled, in part, by grain size and the proportion of suspended to bedload sediments. The presence of rarely documented swept ripples on exhumed accretion surfaces is attributed to rapid decline in water levels and downstream re-entry of overbank floodwaters into the channel. Rill casts, roots and disrupted mudstones low down in channel bodies indicate periods of near-dryness. Laterally extensive sheet sandstones were formed by episodic flows in broad, sandbed channels. The fluvial sediments were primarily intrabasinally sourced with extrabasinal sediments brought in during major floods from upland source areas or reworked from local storage in the basin, representing a supply limited system. The upward change in cement composition from mainly calcite and ankerite to dolomite and gypsum with minor celestine implies increasingly saline groundwater and progressive aridification, supporting Late Palaeozoic palaeoclimatic models. By integrating petrographic data with sedimentology, a plethora of information about ancient landscapes and climate is provided, allowing a fuller comparison between the Clear Fork Formation and modern dryland alluvial plains. [ABSTRACT FROM AUTHOR]

Roof shale floras help understand the transition of vegetational landscapes from a peat-forming environment to a clastic one, but are seldom investigated in the Cathaysian province (typical present day China and East Asia). Here the roof shale flora of Coal Seam 6 from the lower Permian Taiyuan Formation of the Wuda Coalfield, Inner Mongolia, is systematically described and its ecostratigraphic and phytogeographic implications are discussed. The flora is composed of seven plant groups, including Lepidodendrales, Medullosales, Gigantopteridales, Peltaspermales, Noeggerathiales, Cordaitales and Cycadales. Many of these taxa are also documented in Euramerica, and the floral composition indicates a more intimate relationship between Cathaysia and Euramerica during the Cisuralian than previously thought. However, there are few genera and species in common with those of the underlying peat-forming flora. Moreover, the flora is hardly comparable with the commonly known flora of the Taiyuan Formation. Such assemblage differences are very likely due to changes of taphonomic and environmental phases, rather than evolutionary floral succession. For a full and more precise understanding of the floral composition, succession and the floristic discrepancy in different depositional environments, an ecostratigraphic investigation on the Late Palaeozoic of Cathaysia is advocated. [ABSTRACT FROM AUTHOR]

Scleractinian corals appeared during the Anisian period of the Triassic after the end-Permian mass extinction, which in Triassic were distinct from the Jurassic-Cretaceous scleractinian corals. The study on Triassic scleractinian coral fauna as a separate field is significant for exploring the development and evolution of modern corals and investigating environmental changes since the Mesozoic. The first Triassic coral in China was reported in 1925, and since then, nearly 25 articles dealing with taxonomy and 17 papers about fossil reports on Triassic scleractinian corals in China have been published, which refer to 60 genera and 312 species, 49 localities and 25 strata. In this paper, the history, taxonomy, localities, stratigraphic distribution, current research, and existing knowledge gaps of the Triassic scleractinian corals in China are reviewed. More specifically, the research findings of the Triassic scleractinain coral in China since 1925 are discussed; the species of the Triassic scleractian coral fossil reported in China, has been examined and its synonyms have been sorted out; the geographical distributions of the Middle and Late Triassic scleractinian corals in China are systematically treated; the Triassic coral biostratigraphy in China has been improved; and the stratigraphic ranges of existing genera and species are provided. The above conclusions are presented in the form of complete figures. At the same time, we analyzed shortcomings in current research and identified productive future research directions of the Triassic scleractinian corals in China. [ABSTRACT FROM AUTHOR]

Malacostracan crustaceans of the fossil order Pygocephalomorpha are conspicuous elements in brackish to freshwater faunas in the upper Carboniferous of Laurentia and lower Permian of Gondwana. A pronounced sexual dimorphism is recognizable within its members, with Pygocephalomorpha females bearing oöstegites: modified epipodites that hold a brood pouch where the eggs develop until juvenile stage, with no planktonic dispersal of larvae. The preservation of oöstegites is quite rare and is described here for the first time from the American continents. The specimens, ventrally preserved Liocaris huenei females bearing oöstegites, come from the Irati Formation, a lower Permian sequence of the Paraná Basin, from an outcrop in southern Brazil. The oöstegites are similar to those previously described for Pygocephalomorpha, displaying seven pairs of overlapping epipodites that cover the whole cephalothorax. The scarcity of these structures in the fossil record may be explained by taphonomic bias (it requires ventrally preserved crustaceans) but more likely by palaeobiological aspects, such as preservation of an ovigerous moult. The record from the Irati Formation suggests that pygocephalomorphs had seasonal reproduction, with females maturing at the same time and acquiring oöstegites that would be lost after the release of juveniles. This record confirms the relationship of the Brazilian Liocaris Beurlen to the English Pygocephalus Huxley and South African Notocaris Broom pygocephalomorphs and provides an insight into its palaeoecological significance. [ABSTRACT FROM AUTHOR]

In north-west Europe, the Permian is limited to the New Red Sandstone and the restricted marine facies of the Zechstein, yet elsewhere it is constituted of thick marine deposits with an abundant shelly fauna. One of the most notable sites for the marine Permian is the island of Timor in south-east Asia, where thick, olistostromic blocks of limestone have yielded 1000+ shelly species. Over a third of these are stalked echinoderms, both crinoids and blastoids, two diverse Palaeozoic groups that would be devastated by the end-Permian mass extinction. [ABSTRACT FROM AUTHOR]

An Early Permian glacial diamictite forms a distinctive unit within the Falkland Islands sedimentary succession and two aspects of its significance have recently been serendipitously enhanced. Fossil discoveries in exotic limestone clasts bear on palaeogeography, whilst a series of mineral-exploration borehole cores have allowed a detailed study of the sedimentary record of deglaciation that followed deposition of the diamictite. Statistical analysis of reflectance and XRF core-scanning data has identified likely Milankovitch periodicities and enabled tentative time-scale modelling. The 'icehouse to greenhouse' transition appears to have spanned approximately 1.2 million years, with waning cycles of re-advance superimposed on overall glacial retreat. The new results play into a long-debated geological paradox: although the Falkland Islands are now proximal to the South Atlantic coastline of South America, their geology bears an uncanny resemblance to that of the Cape Fold Belt and Karoo Basin in South Africa. This puzzled the geological pioneers, but became readily explicable when first continental drift and then plate tectonics were invoked to reconstruct the break-up of the Gondwana supercontinent-although the details remain controversial. One of the key stratigraphical correlation levels throughout the major fragments of southern Gondwana-South Africa, South America, Antarctica and Australia-is the glacigenic deposit left behind by the extensive, Late Carboniferous to Early Permian regional glaciation; in the Falkland Islands it is designated the Fitzroy Tillite Formation. [ABSTRACT FROM AUTHOR]

The paper shows thermal tests results (thermal conductivity, specific heat) carried out during the research project to recognize the potential of hot dry rocks for heat and electricity production in Poland. Analysis of such parameters of the rock medium has fundamental significance in search of structures for location of enhanced geothermal systems (EGS). Analyses of thermal conductivity as well as specific heat determine the possibility of effective extraction of heat from hot rock formations and its efficient transfer to the land surface. Reservoir rock should be characterized by the lowest possible porosity and permeability, and the highest possible thermal conductivity. In order to recognize reservoir parameters of rocks that form potential reservoirs for EGS, 300 samples of sedimentary rocks were taken from 11 wells located in central Poland. For samples, sizes of which enabled measurement of thermal parameters, tests of thermal conductivity and specific heat were carried out. Independently, measurements of porosity were made. The porosity magnitude determines values of measured thermal parameters. Measurements of thermal conductivity of rocks were made for 24 samples collected from Triassic, Permian and Carboniferous deposits in six wells. Measurements of specific heat on rock samples were made for 20 rock samples. Among sedimentary rocks, principally sandstones and limestones with reservoir parameters favourable for this type of systems are considered to be petrogeothermal reservoirs and are often characterized by favourable thermal parameters for EGS. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Early Permian (272±2Ma) diabase dikes from the Linxi area in central Inner Mongolia of NEChina have high MgO(10.4-12.3wt%),Cr (301-448ppm) and Ni (167-233ppm) concentrations, and show enrichments in large ion lithophile element (LILE) and light rare earth elements (REE) but depletions in high field strength element (HFSE, e.g., Nb and Ta), with depleted mantle-type Sr [87Sr/86Sr (i)=0.70315 - 0.70362], Nd [εNd (t)=+6.8 - +7.4], Pb [206Pb/204Pb (i)=18.10 - 18.16] and zircon Hf [εHf (t)=+14.7 - +19.1] isotopic compositions, but slightly higher zircon δ18O (5.2 - 6.0 ‰ with an average of 5.7 ‰) than normal mantle. The combined geochemical data indicate their derivation from a depleted mantle metasomatized by recycled crustal component. Elemental and isotopic modeling results suggest that the primary magma was produced through 5 % to 10 % melting of a depleted mantle, which contained approximately 1 % sediment fluid released from the subducted paleo-Asian Ocean. Considering the widespread distribution of contemporaneous mafic rocks across the central Inner Mongolia, which show REE patterns from E-MORBs to normal MORBs, we propose a petrogenetic link between the Early Permian mafic magmatism and a back-arc extension in response to northward subduction of the paleo-Asian Ocean. The Permian mafic magmatism and the new age constraints from the metamorphic and sedimentary records in this area tend to indicate the ultimate closure of the paleo-Asian Ocean by the end of Paleozoic. [ABSTRACT FROM AUTHOR]

Occupying the role of primary consumer and having an early-middle Permian age range, caseids ( Caseasauria, Synapsida) are fundamental to the interpretation of the early history of terrestrial vertebrate ecosystems. Despite this importance, no comprehensive, species-level phylogenetic study of Caseidae has yet been performed. Herein, we present a phylogenetic analysis of the group, using gap weighting to include poorly known taxa. Besides the description and comments on the resultant topologies, some more general issues concerning cladistic methodologies are briefly addressed. This study highlights the importance of a total-evidence approach, including as many within-group taxa and characters as possible. Continuously varying characters, in the form of indices derived from measurement of individual skeletal elements, proved to be highly important, adding significantly to the resolution of, and support for, recovered trees. The utility of the postcranial skeleton in understanding relationships among basal synapsids is highlighted. [ABSTRACT FROM AUTHOR]

The location of the suture between the Yangtze craton and the Cathaysia block is uncertain in the west. Three proposed locations for the western segment of the suture all go through Guangxi but are up to ~150 km apart. Inherited zircon crystals from the Darongshan Permian S-type granitoid plutons, which are derived from the lower crust and occur north of the southernmost location for the suture, yield U-Pb ages with a major peak at ~960 Ma. The εHf ( t) values of the inherited zircons with ages around the major peak vary from +6.4 to −23.4. The age distribution and Hf isotope variations of the inherited zircons are remarkably similar to those of Precambrian detrital zircon crystals from the western Cathaysia block but strikingly different from those of Precambrian detrital zircon crystals from the Yangtze craton. These results indicate that the western part of the suture is situated to the north of the Darongshan granitoid belt. [ABSTRACT FROM AUTHOR]

The Lower Triassic Mineral Mountains area (Utah, USA) preserves diversified Smithian and Spathian reefs and bioaccumulations that contain fenestral-microbialites and various benthic and pelagic organisms. Ecological and environmental changes during the Early Triassic are commonly assumed to be associated with numerous perturbations (productivity changes, acidifica-tion, redox changes, hypercapnia, eustatism and temperature changes) post-dating the Permian-Triassic mass extinction. New data acquired in the Mineral Mountains sediments provide evidence to decipher the relationships between depositional environments and the growth and distribution of microbial structures. These data also help to understand better the controlling factors acting upon sedimentation and community turnovers through the Smithian-early Spathian. The studied section records a large-scale depositional sequence during the Dienerian(?)-Spathian interval. During the transgression, depositional environments evolved from a coastal bay with continental deposits to intertidal fenestral-microbial limestones, shallow subtidal marine sponge-microbial reefs to deep subtidal mud-dominated limestones. Storm-induced deposits, microbialite-sponge reefs and shallow subtidal deposits indicate the regression. Three microbialite associations occur in ascending order: (i) a red beds microbialite association deposited in low-energy hypersaline supratidal conditions where microbialites consist of microbial mats and poorly preserved microbially induced sedimentary structure; (ii) a Smithian microbialite association formed in moderate to high-energy, tidal conditions where microbialites include stromatolites and associated carbonate grains (oncoids, ooids and peloids); and (iii) a Spathian microbialite association developed in low-energy offshore conditions that is preserved as multiple decimetre thick isolated domes and coalescent domes. Data indicate that the morphologies of the three microbialite associations are controlled primarily by accommodation, hydrodynamics, bathymetry and grain supply. This study suggests that microbial constructions are controlled by changes between trapping and binding versus precipitation processes in variable hydrodynamic conditions. Due to the presence of numerous metazoans associated with microbialites throughout the Smithian increase in accommodation and Spathian decrease in accommodation, the commonly assumed anachronistic character of the Early Triassic microbialites and the traditional view of prolonged deleterious conditions during the Early Triassic time interval is questioned. [ABSTRACT FROM AUTHOR]

The new genus and species Lutevanaphis permiana gen.n. et sp.n., represents the oldest Aphidomorpha, new superfamily Lutevanaphidoidea superfam.n. and new family Lutevanaphididae. This taxon is described from the Middle Permian of the Lodève Basin, southern France. The presence of very small Aphidomorpha in the Middle Permian contradicts the hypothesis of the ' Lilliput effect' that is presumed to have affected the insect fauna during the Early to Middle Triassic, after the end- Permian crisis. Very small insects were present well before the end of the Permian; their relative rarity is attributable probably to taphonomic biases. [ABSTRACT FROM AUTHOR]

In the last 15 years, the discovery of several new actinopterygian fish faunas from the Early and Middle Triassic of the Tethys, cast new light on the timing, speed and range of their recovery after the end-Permian crisis. In addition to several new taxa having been described, the stratigraphical and geographical record of many others have been greatly extended. In fact, most of the new fossiliferous sites are in southern China, thus at the Eastern end of the Tethys, and furthermore a few are somewhat older (Chaohu, Panxian, Luoping) than the major classical Western Tethys sites (Monte San Giorgio). Following these new finds, it is possible to have a better definition of the Triassic recovery stages. Indeed, after a quite short phase till the end of the Smithian (Olenekian, Early Triassic) in which a rather consistent fauna was present all around the Pangea coasts, a major radiation occurred in the Early-Middle Anisian after the new Middle Triassic fish fauna already appeared in the late Early Triassic, thus occuring well before what was previously supposed from the Alps localities. Furthermore, the new assemblages from southern China point to an early broader differentiation among the basal neopterygians rather than in the 'subholosteans', the group that was then dominant in the Western Tethys since the Late Anisian. It stands that during the Norian a new basal neopterygian radiation gave rise to several new branches that dominated the remaining part of the Mesozoic. [ABSTRACT FROM AUTHOR]

Analyses of 3-D seismic data reveal that pre-Triassic basins are present underneath the Mesozoic North Træna Basin (Lofoten Margin, Norway). These are linked to a Cordilleran-style metamorphic core complex that developed in Palaeozoic times, including rotated fault blocks with hanging wall 'growth' wedges, bounded by listric faults that sole into a sub-horizontal detachment. On the basis of similarity in age, structural style and transport direction, we propose a kinematic link with a Permian mylonitic detachment documented onshore. This study presents the first offshore evidence for Palaeozoic detachment faulting, elucidating the mechanisms behind the long-lived exhumation history of the Lofoten basement. [ABSTRACT FROM AUTHOR]

A Kubergandian (Kungurian) fusuline fauna from the lower part of the Lugu Formation in the Cuozheqiangma area, central Qiangtang Block is described. This fusuline fauna belongs to the Southern Transitional Zone in palaeobiogeography, and is characterised by the presence of the distinctive bi-temperate genus Monodiexodina and many genera common in lower latitude Tethyan areas such as Parafusulina and Pseudodoliolina. The occurrence of Monodiexodina in the fauna confirms that the seamount-type carbonates of the Lugu Formation did not originate from the Palaeotethys Ocean, but rather from a branch of the Neotethys Ocean after the rifting of the Qiangtang Block from the Tethys Himalaya area in the Artinskian. [ABSTRACT FROM AUTHOR]

The peltasperm foliage Autunia naumannii (Gutbier) Kerp and possible peltasperm fructifications are for the first time described from the uppermost Taiyuan Formation of earliest Permian age near Wuda, Inner Mongolia. This is the oldest record of this group on the North China Block (Sino-Korean Platform), indicating an early migration into this area. Data of other occurrences in China demonstrate independent radiations of the group in Cathaysia. All known records indicate that peltasperms probably originated in the tropical extrabasinal areas of Euramerica, and subsequently migrated within the tropical belt and experienced independent regional radiations in Europe, the southwestern United States and on the North China Block. The present discovery of Autunia naumannii (Gutbier) Kerp in China adds a common floral component between the Euramerican and Cathaysian floras, providing more evidence indicating mutual migration of floral elements between Cathaysia and Euramerica. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Geochronology of oil-gas accumulation (OGA) is a challenging subject of petroleum geology in multi-cycle superimposed basins. By K-Ar dating of authigenic illite (AI) and fluid inclusion (FI) analysis combined with apatite fission track (AFT) thermal modeling, a case study of constraining the OGA times of the Permian reservoirs in northeast Ordos basin (NOB) has been conducted in this paper. AI dating of the Permian oil-gas-bearing sandstone core-samples shows a wide time domain of 178-108 Ma. The distribution of the AI ages presents 2-stage primary OGA processes in the Permian reservoirs, which developed in the time domains of 175-155 Ma and 145-115 Ma with 2-peak ages of 165 Ma and 130 Ma, respectively. The FI temperature peaks of the samples and their projected ages on the AFT thermal path not only present two groups with a low and a high peak temperatures in ranges of 90-78°C and 125-118°C, respectively corresponding to 2-stage primary OGA processes of 162-153 Ma and 140-128 Ma in the Permian reservoirs, but also appear a medium temperature group with the peak of 98°C in agreement with a secondary OGA process of c.∼30 Ma in the Upper Permian reservoirs. The integrated analysis of the AI and FI ages and the tectono-thermal evolution reveals that the Permian reservoirs in the NOB experienced at least 2-stage primary OGA processes of 165-153 Ma and 140-128 Ma in agreement with the subsidence thermal process of the Mid-Early Jurassic and the tectono-thermal event of the Early Cretaceous. Then, the Upper Permian reservoirs further experienced at least 1-stage secondary OGA process of c.∼30 Ma in coincidence with a critical tectonic conversion between the slow and the rapid uplift processes from the Late Cretaceous to Neogene. [ABSTRACT FROM AUTHOR]

Two new tetrapod burrow casts from the Naobaogou Formation (Middle or Late Permian) of Nei Mongol, China are described. It marks the first pre-Cenozoic tetrapod burrow from China, and one of the earliest records of tetrapod burrows. Comparison to other Permian and Triassic burrows suggests that these burrows were created by tetrapod slightly smaller than Lystrosaurus. Deduced from the morphology and sizes of two burrows and known tetrapods of the Naobaogou Formation, the burrow should be the production of a therapsid, most likely a dicynodon. These burrows indicate a seasonal climate and this area was semiarid or arid during that time. [ABSTRACT FROM AUTHOR]

Based on its Permian-Triassic stratigraphic and biotic evolution, we correlate the SE Pamir to the Karakoram terrane, and we consider them equivalent, along with the Central Pamir, to the Qiantang Terrane of Tibet, all of Palaeozoic Gondwanan ancestry. We prove the occurrence of a marked Cimmerian unconformity, documented by lowermost Jurassic deposits suturing intensively faulted and folded Permian and Triassic units, which suggests that the South Pamir collided around the T-J boundary with the Central Pamir along the Rushan-Pshart suture. Collision of the Karakoram to the South Pamir happened slightly later along the Wakhan-Tirich Boundary Zone. Progressive time shifting of deformation can be related to the complex setting of the Cimmerian belt, which was subdivided into minor blocks by incipient oceanic basins, providing strong crustal mobility. [ABSTRACT FROM AUTHOR]

The family Mesopsychidae Tillyard, 1917 presently consists of ten described genera from the Early Permian to the Early Cretaceous of Australia, China, Kyrgyzstan, Russia, South Africa, Tajikistan, and Ukraine. Herein, a new genus and a new species of fossil mesopsychid, Epicharmesopsyche pentavenulosa gen. et sp. nov., is described from the Middle Jurassic Jiulongshan Formation of Inner Mongolia, China, supplementing the family-level diversity. The well-preserved, new material reveals many characters, including antennae, wing venation, shape and genitalia that increase our morphological understanding of the family, although unfortunately the mouthparts and most of the legs are not preserved. Diagnosis of the Mesopsychidae is emended to include a four- or five-branched MP in both the fore- and hind wings. This is the first documentation of a wing coupling structure in the Mesopsychidae, consisting of three to four frenula bristles on the humeral lobe at the base of the costal margin of both hind wings. Asymmetrical shape and size of the left and right wings on a specimen of E. pentavenulosa gen. et sp. nov., seems to be a common condition for mesopsychid taxa from northeastern China. [ABSTRACT FROM AUTHOR]

Compaction rates of sediments or volcaniclastic material are needed to reconstruct original thickness of a bed, which in turn is required to reconstruct subsidence rates, sea-level rise, or in the case of volcaniclastic, the location or direction of the eruption site. The knowledge of compaction rates can also aid in the reconstruction of deformed fossils. The known shape of deformed fossils can allow the determination of the compaction they experienced. Here we report the compaction rate in an early Permian volcanic tuff from Wuda, Inner Mongolia, determined from the deformation of standing tree fern stems of known anatomy. The compaction rate has been found to be 0.56 in this case, indicating that 44% of original thickness remains. [ABSTRACT FROM AUTHOR]

We present the first study of micro-crustaceans (ostracods) associated with microbial crusts in the aftermath of the most devastating extinction, the end- Permian extinction ( EPE). These post-extinction microbialites dominated shallow shelf marine environments and were traditionally considered as devoid of any associated fauna. We present a micro-palaeontological analysis of a large record from microbial and non-microbial settings following the EPE. This dataset documents the proliferation of ostracods strictly associated with microbialites. Based on the diet of extant ostracods and uniformitarianism, we propose that the abundant microbes in the mats served as an unlimited food supply. Photosynthetic cyanobacteria may also have locally provided oxygen under low oxygen conditions interpreted by others for the microbialites. Microbialites provided a specialised environment that may have acted as refuge for ostracods in the immediate aftermath of the EPE. The surviving faunas may have been progenitors for the starting of the latter radiation. [ABSTRACT FROM AUTHOR]

Chondrichthyans are newly reported from the autochthonous Wordian Khuff Formation (middle Permian), cropping out in well-exposed, low-palaeolatitude sections in the interior Haushi-Huqf area of Oman. The shark remains comprise isolated teeth, dermal denticles and fin spines and have been recovered by processing limestone in buffered acetic acid from bulk rock samples. The fauna consists of mainly ctenacanthiform and hybodontiform taxa, identified as Glikmanius cf. myachkovensis, Glikmanius culmenis sp. nov., Omanoselache hendersoni gen. et sp. nov., Omanoselache angiolinii gen. et sp. nov., cf. Omanoselache sp., Reesodus underwoodi gen et sp. nov., Teresodus amplexus gen. et sp. nov., Gunnellodus bellistriatus, Khuffia lenis gen. et sp. nov., Khuffia prolixa gen. et sp. nov. and Euselachii sp. indet. Additional specimens include rare teeth of the lonchidiid cf. 'Palaeozoic Genus 1' sp., of the neoselachian Cooleyella cf. fordi and a further indeterminate neoselachian, of an indeterminate petalodont and of the holocephalan Deltodus aff. mercurei and Solenodus cf. crenulatus. Fin spines add a further two taxa, Nemacanthus sp. and Amelacanthus cf. sulcatus, which have neoselachian affinities and therefore an unclear relationship to the recovered teeth. The occurrence of Nemacanthus within this Wordian fauna represents the oldest record of this taxon and its only known occurrence in the Palaeozoic. Of the remaining genera, Glikmanius has previously been recorded from the Wordian, whereas for all the others, this study represents their youngest known stratigraphic occurrence and first occurrence in Guadalupian (middle Permian) strata. This adds significantly to our knowledge of the global diversity of chondrichthyans preceding the end-Guadalupian biotic crisis. Palaeogeographically, for all taxa, this study represents the first record from the western fringe of the marine Neotethyan basin, and only Cooleyella was previously known from the southern (Gondwanan) part of the Pangaean continental margin. [ABSTRACT FROM AUTHOR]

Forests are expected to expand into northern polar latitudes in the next century. However, the impact of forests at high latitudes on climate and terrestrial biogeochemical cycling is poorly understood because such forests cannot be studied in the modern. This study presents forestry and geochemical analyses of three in situ fossil forests from Late Permian strata of Antarctica, which grew at polar latitudes. Stem size measurements and stump spacing measurements indicate significant differences in forest density and canopy structure that are related to the local depositional setting. For forests closest to fluvial systems, tree density appears to decrease as the forests mature, which is the opposite trend of self-thinning observed in modern forests. We speculate that a combination of tree mortality and high disturbance created low-density mature forests without understory vegetation near Late Permian river systems. Stable carbon isotopes measured from permineralized wood in these forests demonstrate two important points: (i) recently developed techniques of high-resolution carbon isotope studies of wood and mummified wood can be applied to permineralized wood, for which much of the original organic matter has been lost and (ii) that the fossil trees maintained a deciduous habit at polar latitudes during the Late Permian. The combination of paleobotanical, sedimentologic, and paleoforestry techniques provides an unrivaled examination of the function of polar forests in deep time; and the carbon isotope geochemistry supplements this work with subannual records of carbon fixation that allows for the quantitative analysis of deciduous versus evergreen habits and environmental parameters, for example, relative humidity. [ABSTRACT FROM AUTHOR]

The Liangshan and Qixia formations in the Sichuan Basin of central China were formed in the earlier middle Permian. Based on outcrop observation of the Changjianggou section at Shangsi, Guangyuan region and 3rd-order sequence division in typical drillings, one-dimensional spectrum analysis has been used to choose the better curve between the natural gamma ray spectrometry log(ln (Th/K)) in Well-Long17 and the gamma ray log(GR) in Well-Wujia1, respectively, for identifying Milankovitch cycles in Sequence PSQ1 which comprises the Liangshan and Qixia formations, and then to identify the variation in the Milankovitch cycle sequences. On this basis, the system tract and 4th-order sequence interfaces in Sequence PSQ1 were found via two-dimensional spectral analysis and digital filtering. Finally, a high-frequency sequence division program was established. Among these cycles, long eccentricity (413.0 ka) and short eccentricity (123.0 ka) are the most unambiguous, and they are separately the major control factors in forming 4th-order (parasequence sets) and 5th-order (parasequences) sequences, with the average thicknesses corresponding to the main cycles being 11.47 m and 3.32 m in Well-Long17, and 14.21 m and 3.79 m in Well-Wujia1, respectively. In other words, the deposition rate in the beach subfacies is faster than that of the inner ramp facies. The ln(Th/K) curve is more sensitive than the GR as the index of relatively ancient water depth in carbonate deposition. One-dimensional spectrum analysis of ln(Th/K) curve could distinguish the Milankovitch cycle sequences that arose from the Precession cycle (20.90 ka), with a much higher credibility. Sequence PSQ1 in Well-Long17 contains 10 4th-order sequences, and the growth span of Sequence PSQ1 consisting of the Liangshan and Qixia formations is about 4.13 Ma. The single deposition thickness of the long eccentricity cycle sequence has the characteristics of thinning and then thickening in the two-dimensional spectrum, which could be used to identify the system tract interface of the 3rd-order sequence. The precession sequence thickness remains stationary. As a result, the early deposition rate in the mid-Permian of the Sichuan basin was very slow, remaining nearly stationary, and this reflects a sustained depositional environment. Whole-rock carbon and oxygen isotope curves could also prove this point Milankovitch cycle sequence studies provide a basis for paleoenvironmental analysis and, as such, can be used to analyze ancient climate change, calculate deposition rate and deposition time, and carry out fine isochronous stratigraphic correlation. [ABSTRACT FROM AUTHOR]

The Napo-Qinzhou Tectonic Belt (NQTB) lies at the junction of the Yangtze, Cathaysia and Indochina (North Vietnam) Blocks, which is composed of five major lithotectonic subunits: the Qinzhou-Fangcheng Suture Zone (QFSZ), the Shiwandashan Basin (SB), the Pingxiang-Nanning Suture Zone (PNSZ), the Damingshan Block (DB) and the Babu-Lingma Suture Zone (BLSZ). On the basis of geochemical compositions, the Permian mafic igneous rocks can be divided into three distinct groups: (1) mafic igneous rocks (Group 1) from the Longjing region in the PNSZ and Hurun region in the BLSZ, which are characterized by intermediate Ti, P and Zr with low Ni and Cr contents; (2) mafic igneous rocks (Group 2) from the Naxiao and Chongzuo region in the DB, characterized by low-intermediate Ti, P and Zr with high Ni and Cr concentrations; and (3) mafic igneous rocks (Group 3) from the Siming region in the Jingxi carbonate platform of the northwestern margin of the NQTB, with intermediate-high Ti, P and Zr and low Ni and Cr contents. The Group 1 rocks yield a weighted mean 206Pb/238U age of 250.5±2.8 Ma and are geochemically similar to basalts occurring in back-arc basin settings. The Group 2 rocks exhibit geochemical features to those basalts in island arcs, whereas the Group 3 rocks show geochemical similarity to that of ocean island basalts. All three groups are characterized by relatively low εNd( t) values (-2.61 to +1.10) and high initial 87Sr/86Sr isotopic ratios (0.705309-0.707434), indicating that they were derived from a subduction-modified lithospheric mantle and experienced assimilation, fractional crystallization, and crustal contamination or mixing during magmatic evolution. Accordingly, we propose the existence of an arc-back arc basin system that developed along the NQTB at the border of SW Guangxi Province (SW China) and northern Vietnam, and it was formed by continued northwestward subduction of the Cathaysian (or Yunkai) Block under the Yangtze Block, and northeastward subduction of the Indochina Block beneath the Yangtze Block during Permian time. [ABSTRACT FROM AUTHOR]

Siliciclastic intervals in Lower Permian carbonate-siliciclastic cyclothems in western Kansas record climate control on facies progression, deposition and preservation. The 26 000 km2 study area comprises seven marine-continental (carbonate-siliciclastic) cyclothems caused by glacioeustasy. Core data and a three-dimensional geological model provide a detailed view of the sub-surface on a gently sloping ramp. Siliciclastic intervals in the cyclothems are fine-grained red beds with extensive pedogenic features, indicating a continental origin. Bed geometry (sheet-like deposits that thin to the east), lateral grading, grain size (very fine-grained sand to silt) and grain angularity (sub-angular to angular) suggest that the sediment is loess sourced from the west, probably the Ancestral Rocky Mountains. There is a repeated record of glacial-cycle-scale, climate-controlled cyclicity within siliciclastic intervals that has not been recognized previously. Aeolian silt grain size coarsens upward towards the middle, then fines upward in each siliciclastic interval. When sea-level was high (interglacial) and carbonate production flourished, aeolian sedimentation nearly ceased, suggesting increased vegetation and rainfall at the source. As sea-level fell, fine-grained siliciclastic sediments were deposited under relatively dry, but seasonally wet conditions on an exposed ramp. Laterally graded coarser grained siliciclastic sediments with diagnostic fabrics indicate drier conditions with seasonal rainfall during a continued relative fall in sea-level. The coarsest siliciclastic sediments were deposited during the lowest sea-level and driest conditions, but still with sufficient seasonal moisture to allow vegetative cover and bioturbation. Subsequent upward fining is correlated with sedimentological indications of wetter conditions during relative sea-level rise. Unlike common sequence stratigraphic models that relate siliciclastic sediment accumulation to base-level rise, continental deposits were preserved because plants and pedogenesis stabilized aeolian sediment. The aggradational landscape formed by this process had several metres of positive relief that reduced accommodation for overlying marine carbonate strata. Thus, this mechanism for continental siliciclastic aggradation has a significant effect on sequence stratigraphic architecture. [ABSTRACT FROM AUTHOR]

Tracks and trackways of the vertebrate ichnotaxon Ichniotherium sphaerodactylum and a trace of the invertebrate ichnotaxon Striatichnium bromackerense are described for the first time in association outside of Europe. The tracks are identified as I. sphaerodactylum based on their characteristic rounded digit ends, the ovoid sole-pad of the pedal imprint and the increase in digit lengths from digits I-IV, and the invertebrate trace is identifiable as S. bromackerense based on the band-like systems of distally bifurcated striae. The tracks of I. sphaerodactylum are the largest known to date and represent rare evidence of large-bodied terrestrial vertebrates in the Kildare Capes Formation of Prince Edward Island, Canada. Morphometric differences between ichnospecies of Ichniotherium and other ichnospecies previously collected from Prince Edward Island are examined in a multivariate analysis, and results suggest that the distance between the manus and pes of the same imprint pair, the width of pace and the length of certain digits is useful for species identification. The association between I. sphaerodactylum and S. bromackerense was previously known only from the Bromacker quarry, Tambach Formation, Germany, which is interpreted as a seasonally dry, semi-arid upland environment. The co-occurrence of these traces suggests that the Eldon locality of Prince Edward Island is similar in depositional environment to the Bromacker quarry in Germany, and allows for comparison of these two localities for the first time. As diadectids are thought to be the trackmakers of Ichniotherium, the Eldon locality of the Kildare Capes Formation may, with further work, be considered as another example of the rare, herbivore-dominated palaeoenvironment, which is generally uncharacteristic of the Early Permian of North America. [ABSTRACT FROM AUTHOR]