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The southeastern Central Asian Orogenic Belt (CAOB) records the assembly process between several micro-continental blocks and the North China Craton (NCC), with the consumption of the Paleo-Asian Ocean (PAO), but whether the S-wards subduction of the PAO beneath the northern NCC was ongoing during Carboniferous–Permian time is still being debated. A key issue to resolve this controversy is whether the Carboniferous magmatism in the northern NCC was continental arc magmatism. The Alxa Block is the western segment of the northern NCC and contiguous to the southeastern CAOB, and their Carboniferous–Permian magmatism could have occurred in similar tectonic settings. In this contribution, new zircon U–Pb ages, elemental geochemistry and Sr–Nd isotopic analyses are presented for three early Carboniferous granitic plutons in the southwestern Alxa Block. Two newly identified aluminous A-type granites, an alkali-feldspar granite (331.6 ± 1.6 Ma) and a monzogranite (331.8 ± 1.7 Ma), exhibit juvenile and radiogenic Sr–Nd isotopic features, respectively. Although a granodiorite (326.2 ± 6.6 Ma) is characterized by high Sr/Y ratios (97.4–139.9), which is generally treated as an adikitic feature, this sample has highly radiogenic Sr–Nd isotopes and displays significantly higher K2O/Na2O ratios than typical adakites. These three granites were probably derived from the partial melting of Precambrian continental crustal sources heated by upwelling asthenosphere in lithospheric extensional setting. Regionally, both the Alxa Block and the southeastern CAOB are characterized by the formation of early Carboniferous extension-related magmatic rocks but lack coeval sedimentary deposits, suggesting a uniform lithospheric extensional setting rather than a simple continental arc.

The Devonian/Carboniferous Boundary (DCB) interval is associated with mass extinction, isotope excursions and a short glacial episode. This study investigates how boundary extinction and environmental change is expressed in the glacial high-palaeolatitudinal record of the Bolivian Altiplano (western Gondwana). A latest Devonian and early Carboniferous section has been investigated using sedimentology, palynology, total organic carbon and bulk δ13Corganic. The Colpacucho Formation is a Late Devonian shelfal–marine siliciclastic sequence. It is overlain in the study area by a unit of coarse sandstones and sandy diamictites, interpreted as glaciomarine. This distinctive glaciomarine unit is at least 7 km wide and 60–120 m thick with a variably incisive basal contact (Retispora lepidophyta and significant palynological assemblage changes. This includes the loss of the Umbellasphaeridium saharicum phytoplankton bioprovince, endemic to Gondwana. Marine and terrestrial palynological extinctions are synchronous with a 2 ‰ positive carbon isotope excursion interpreted to be reflective of changes in organic matter delivery and preservation during an interval of environmental stress. These results inform wider debates on global environmental change and mass extinction at the DCB.

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.

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.

Detrital zircon populations from six samples of upper Triassic sandstone (Algarve Basin) were analysed, yielding mostly Precambrian ages. zircon age populations of the Triassic sandstone sampled from the western and central sectors of the basin are distinct, suggesting local recycling and/or lateral changes in their sources. Our findings and the available detrital zircon ages from the Palaeozoic terranes of SW Iberia, Nova Scotia and NW Morocco were jointly examined using the Kolmogorov–Smirnov test and multidimensional scaling diagrams. The obtained results enable direct discrimination of competing Laurussian-type and Gondwanan-type sediment sources, involving recycling and mixing relationships. The detrital zircon populations of the Algarve Triassic sandstone are very different from those of the lower–upper Carboniferous Mértola and Mira formations (South Portuguese Zone), upper Devonian – lower Carboniferous Horta da Torre, Represa and Santa Iria formations (Pulo do Lobo Zone), and the late Carboniferous Santa Susana and early Permian Viar basins, which are ruled out as potential sources. The detrital zircon populations of Triassic sandstone from the central sector and those from the Ossa–Morena Zone Ediacaran–Cambrian siliciclastic rocks, upper Devonian – Carboniferous Ronquillo, Tercenas, Phyllite-Quartzite and Brejeira formations (South Portuguese Zone), and Frasnian siliciclastic rocks of the Pulo do Lobo Zone are not statistically distinguishable. Thus, sedimentation in the central sector was influenced by Gondwanan- and Laurussian-type putative sources exposed in SW Iberia, in contrast to the western sector, where Meguma Terrane and Sehoul Block Cambrian siliciclastic rocks allegedly constituted the main (Laurussian-type) sources. These findings provide insights into the denudation of distinctive source terranes distributed along the late Palaeozoic suture zone that juxtaposed the Laurussian and Gondwanan margins.

West Junggar in the southwestern Central Asian Orogenic Belt is a critical area for the study of the Junggar oceanic basin and may also reveal tectonic evolutionary events before the final closure of the Palaeo-Asian Ocean. The sedimentary formations and paragenetic associations of the Upper Carboniferous Chengjisihanshan Formation in southern West Junggar jointly reveal a back-arc basin setting with zircon U–Pb ages of 313–310 Ma for the basaltic rocks. Geochemically, the basaltic rocks are tholeiitic with low SiO2 (47.76–52.06 wt %) and K2O (0.05–0.74 wt %) but high MgO (6.55–7.68 wt %) contents and Mg no. (52.9–58.9) values. They display slightly flat rare earth element patterns with weak positive Eu anomalies, and show enrichments in large ion lithophile elements relative to high field strength elements with negative Nb and Ta anomalies, exhibiting both N-MORB-like and arc-like signatures, similar to the back-arc basin basalt from the Mariana Trough. The high positive zircon εHf(t) and bulk εNd(t) values as well as high initial Pb isotopes, together with relatively high Sm/Yb and slightly low Th/Ta ratios imply a depleted spinel lherzolitic mantle source metasomatized by slab-derived fluids. The field and geochemical data jointly suggest that the volcanic rocks within the Chengjisihanshan Formation were formed in an intra-oceanic back-arc basin above the northwestward subduction of the Junggar oceanic lithosphere in southern West Junggar. The confirmation of the Late Carboniferous back-arc basin basalts, together with other geological observations, indicate that an arc-basin evolutionary system still existed in southern West Junggar at c. 310 Ma, and the Junggar Ocean closed after Late Carboniferous time.

The Ghaleh-Dezh metagranites in the northern Sanandaj–Sirjan Zone (SaSZ) in western Iran are found in a 0.5 km long by 0.3 km wide unit emplaced within the older Precambrian basement. New zircon U–Pb ages confirm that crystallization and emplacement of the protolith of the metagranites occurred at 312 ± 10 Ma and 298 ± 17 Ma in the Upper Carboniferous (Pennsylvanian) – Early Permian, which is consistent with the ages of recently discovered Palaeozoic granites in the northern SaSZ. The studied metagranitic body has been metamorphosed at lower greenschist facies and deformed in ductile–brittle regime due to subsequent reheating events during the Mesozoic. The rocks are metaluminous to slightly peraluminous granites with an A2-type affinity. Initial87Sr/86Sr ratios andεNd(t) contents vary from 0.7037 to 0.7130 and −0.70 to 0.34, respectively.143Nd/144Nd(i)values for the granitic rocks are fairly uniform at ∼0.5123. The geochemical and isotopic evidence indicates that these rocks were generated from a mantle magma with crustal contamination and fractional crystallization. Rb–Sr isochron and40Ar/39Ar K-feldspar ages are 274 Ma and 60–70 Ma, respectively. The older event,c.270 Ma, was likely related to the opening of Neotethys, whereas the younger ages likely relate to collisional events in the region during the closure of Neotethys.

High-pressure low-temperature metamorphic sediments of the Phyllite–Quartzite unitsensu strictoand the Talea Ori group are investigated in the field, microstructurally and by U–Pb dating of detrital zircons to shed light on their palaeogeographic origin. Zircon age spectra with ages >450 Ma of the Phyllite–Quartzite unitsensu strictoindicate a palaeogeographic origin at the northern margin of East Gondwana. In contrast, the lower stratigraphic, siliciclastic formations of the Talea Ori group show a high number of well-rounded Cambrian to Early Carboniferous aged zircons and a Neoproterozoic zircon age spectrum with East Gondwana affinity. Based on the comparison of zircon age data, a possible distal sediment source is the Sakarya Zone at the southern active margin of Eurasia. To reconcile the zircon data with the geological observations we propose different alternative models, or a combination of these, including sediment transport from the Sakarya Zone and/or a westerly source towards the northern margin of Gondwana as well as terrane-displacement of the Sakarya Zone. Also, a palaeogeographic origin of the Talea Ori group at the southern active margin of Eurasia cannot be excluded. This alternative, however, would not be consistent with the usually assumed association of the Talea Ori group with the Plattenkalk unit characterized by a palaeogeographic origin at the northern margin of Gondwana.

The Cambrian–Ordovician metasedimentary rocks of the Meguma terrane (Canadian Appalachians) were extensively intruded by silicic plutons during Middle Devonian to Early Carboniferous times. Syn-plutonic but volumetrically minor mafic-ultramafic intrusions were also emplaced. In most localities, the silicic plutons and mafic-ultramafic intrusions do not appear to be petrogenetically related and are likely derived from different sources. The Attwoods Brook gabbronorite of SW Nova Scotia yielded an in situ zircon weighted-mean 206Pb–238U age of 357.9 ± 3.3 Ma that is within the uncertainty of the age of the neighbouring Wedgeport pluton (357 ± 1 Ma). The Wedgeport pluton is a rare example of a mantle-derived, peraluminous A-type granite within the Meguma terrane. The similar ages and Nd isotopes of the Attwoods Brook gabbronorite (εNd(t) = +1.1 to +4.0) and Wedgeport pluton (εNd(t) = +2.1 to +3.3) suggest the two intrusions are petrogenetically related. Fractional crystallization modelling demonstrates that a parental magma similar to the Attwoods Brook gabbronorite can produce residual silicic liquids that resemble the granites of the Wedgeport pluton, indicating that they could be members of the same intrusive complex. The emplacement of the gabbronorite and Wedgeport pluton occurred during a period of tensional plate stress that was contemporaneous with rifting of the Maritimes Basin that produced the Fountain Lake continental flood basalts and A-type granites of the Cobequid Highlands within the Avalon terrane. It is possible that the Early Carboniferous rocks of SW Nova Scotia are related to the rifted-related magmatism within the Maritimes Basin.

The Daheyan region, situated in the SW of the Bogda Mountains in eastern Tianshan, is important for understanding the accretionary history of the Central Asian Orogenic Belt. We investigated Carboniferous intrusions from the Daheyan area, SW Bogda Mountains, obtaining new zircon U–Pb ages, whole-rock geochemical data and Hf isotope data for these intrusions. Zircon U–Pb dating indicates that syenogranite, diorite, granodiorite and monzonite of the Daheyan intrusions were all formed during late Carboniferous (311–303 Ma) magmatism. The syenogranite has geochemical characteristics of A-type granites that were mainly sourced from melting of juvenile crust. In comparison, the low-Mg-number diorite intrusion, with tholeiite and metaluminous features, was derived from young crust and mixed some mantle materials. The granodiorite and monzonite are both I-type granites, and are both sourced from the melting of juvenile crust. Based on a comprehensive analysis of previous geochronological, geochemical and isotopic data of magmatic and sedimentary rocks in the Bogda–Harlik belt, we consider that late Carboniferous intrusive rocks of the Bogda Mountains formed in an intra-arc extension related to a continent-based arc setting.

The Longmu Co–Shuanghu suture zone, which divides the Qiangtang terrane into the northern and southern Qiangtang blocks, is regarded as a key locality in reconstructing the evolutionary history of the Palaeo-Tethys Ocean and the break-up of Gondwana. However, although low-temperature – high-pressure metamorphic rocks and ophiolites have been documented within the Longmu Co–Shuanghu suture zone, it remains unclear whether it is an in situ suture zone and represents the relic of the main Palaeo-Tethys Ocean. The uncertainty stems mainly from the limited systematic studies of the provenance, palaeontological evidence and depositional settings of strata on either side of the Longmu Co–Shuanghu suture zone (i.e. northern and southern Qiangtang blocks). Here we report new detrital zircon U–Pb ages and palaeontological data from Lower Carboniferous strata (Riwanchaka Formation) of the northern Qiangtang block, central Tibet. The Riwanchaka Formation contains warm-climate biota with Cathaysian affinities. Provenance analysis reveals that the formation has detrital zircon spectra similar to those from strata of the Yangtze Plate, and it contains a large proportion of zircons with ages (~360 Ma) similar to the timing of synsedimentary magmatic arc activity, implying an active continental margin setting associated with northward subduction of the Palaeo-Tethyan oceanic lithosphere. Conversely, the Carboniferous–Permian strata from the southern Qiangtang block contain cool-water faunas of Gondwanan affinity and exhibit minimum zircon crystallization ages that are markedly older than their depositional ages, suggesting a passive continental margin setting. The differences in provenance, palaeontological assemblages and depositional settings of the Carboniferous to Permian strata either side of the Longmu Co–Shuanghu suture zone indicate the existence of an ancient ocean between the northern and southern Qiangtang blocks. Combining the new findings with previous studies on high-pressure metamorphic rocks, arc magmatism and ophiolites, we support the interpretation that the Longmu Co–Shuanghu suture zone is an in situ suture zone that represents the main suture of the Palaeo-Tethys Ocean.

Late to post-Variscan sedimentary basins of Sardinia were influenced during Pennsylvanian to Permian times by two main tectono-sedimentary cycles: a Pennsylvanian to Cisuralian cycle represented mainly by dark limnic deposits, overlain by a Guadalupian to a possibly Lopingian cycle, mostly characterized by red-bed deposits. Lacustrine waterbodies developed in some sedimentary basins that were filled with siliciclastic to frequently early silicified carbonate deposits, depending on the climate and environmental conditions, landscape morphology and tectonic regime. The limnic successions of the lower tectono-sedimentary cycle were deposited in permanent, tens of metres deep lakes in deep, narrow tectonic strike-slip basins under a temperate to warm-humid climate. They started as lakes with terrigenous sedimentary input and developed minor carbonate deposits mainly at the end of their story. Conversely, the red-bed successions of the upper cycle were deposited in ephemeral, shallow playa lakes related to wider basins in an extensive alluvial plain under a hot and arid climate. Here, the siliciclastic sediments are intercalated with thin carbonate beds that are typical of a high evaporation rate. The evolution of the lake type could be related not only to a major climatic shift, but also to the changing morphotectonic conditions of the Variscan chain influencing the local microclimate. Comparisons with coeval successions in the Provence Basin, the Massif Central Aumance basin (France) and the Saar–Nahe Basin (Germany) show both similarities and differences between the basins.

The Upper Famennian (Upper Devonian) Strud locality has yielded very abundant and diversified flora as well as vertebrate and arthropod faunas. The arthropod fauna, mostly recovered from fine shales deposited in a calm, confined floodplain habitat including temporary pools, has delivered a putative insect and various crustaceans including eumalacostracans and notostracan, spinicaudatan and anostracan branchiopods. Here we present the Strud eurypterids, consisting of semi-articulated juvenile specimens assigned to Hardieopteridae recovered from the pool and floodplain deposits, as well as larger isolated fragments of potential adults recovered from stratigraphically lower, coarser dark sandy layers indicative of a higher-energy fluvial environment. The Strud fossils strongly suggest that, as proposed for some Carboniferous eurypterids, juvenile freshwater eurypterids inhabited sheltered nursery pools and migrated to higher-energy river systems as they matured.

Whether the latitudinal distribution of climate-sensitive lithologies is stable through greenhouse and icehouse regimes remains unclear. Previous studies suggest that the palaeolatitudinal distribution of palaeoclimate indicators, including coals, evaporites, reefs and carbonates, has remained broadly similar since the Permian period, leading to the conclusion that atmospheric and oceanic circulation control their distribution rather than the latitudinal temperature gradient. Here we revisit a global-scale compilation of lithologic indicators of climate, including coals, evaporites and glacial deposits, back to the Devonian period. We test the sensitivity of their latitudinal distributions to the uneven distribution of continental areas through time and to global tectonic models, correct the latitudinal distributions of lithologies for sampling- and continental area-bias, and use statistical methods to fit these distributions with probability density functions and estimate their high-density latitudinal ranges with 50% and 95% confidence intervals. The results suggest that the palaeolatitudinal distributions of lithologies have changed through deep geological time, notably a pronounced poleward shift in the distribution of coals at the beginning of the Permian. The distribution of evaporites indicates a clearly bimodal distribution over the past ~400 Ma, except for Early Devonian, Early Carboniferous, the earliest Permian and Middle and Late Jurassic times. We discuss how the patterns indicated by these lithologies change through time in response to plate motion, orography, evolution and greenhouse/icehouse conditions. This study highlights that combining tectonic reconstructions with a comprehensive lithologic database and novel data analysis approaches provide insights into the nature and causes of shifting climatic zones through deep time.

The pressure–temperature–deformation–time (P–T–d–t) record of metagranitic rocks and adjacent diverse rocks of the metavolcano-sedimentary group from the Orlica–Śnieżnik Dome (OSD) in SW Poland is examined. The study aims to better understand the course of the break-up of northern Gondwana and the overprinting Variscan tectonometamorphism in the NE Bohemian Massif. We test the existing hypotheses that explain the Cambro-Ordovician thermal event recorded in the meta-supracrustal group by (i) syn-deformational regional metamorphism or (ii) the contact metamorphism of the (meta)sedimentary rocks around the intruding ~490–500 Ma granitic magmas. In addition, we check the extent and timing of the Variscan prograde and retrograde medium-pressure metamorphism in the OSD. The results imply that Early Palaeozoic monazites, rarely preserved in both rock groups, document ~490–500 Ma volcanic and plutonic events related to the Gondwana's break-up and following disturbance of the Th–U–Pb system during younger, Variscan events. The monazite geochronology reveals no distinct Cambro-Ordovician thermal aureole around the post-granitic orthogneisses. However, no large-scale Variscan juxtaposition is evident between the two main OSD rock groups or within the meta-supracrustal rocks. Consistent P–T–d–t results for the meta-supracrustal rocks and the orthogneisses suggest that their precursors contacted before the Variscan tectonometamorphism. The directly contiguous ortho- and paragneisses together experienced tectonometamorphic processes at maximum depths that correspond to 7.5–8.0 kbar and maximum temperatures of ~600–620°C, as a result of the Variscan collision of Gondwana and Euramerica. The continental collision-related events intensified at ~360 Ma and ~330–340 Ma.

We report three Palaeozoic sedimentary successions in northeastern South China that display markedly different tectonostratigraphic characteristics: the Jiangshan section exhibits an angular unconformity between the Upper Ordovician and Carboniferous stratra; the Shuangming section exhibits a disconformity between the lower Silurian and Upper Devonian strata; and the Xinqiao section exhibits a disconformity between the upper Silurian and Upper Devonian strata. The Shuangming and Xinqiao sections are interpreted to represent the remnant Nanhua foreland basin, whereas the Jiangshan section is in the fold-and-thrust zone of the Wuyi-Yunkai orogen. The Lizhu-Changshan thrust fault in between is interpreted to be the frontal thrust and the boundary of the orogen. Detrital provenance analysis of the Ordovician–Devonian sandstones from the Shuangming and Xinqiao sections shows that the Ordovician–Silurian, mid- to late-orogenic sandstones contain dominantly 860–780 Ma zircon populations and subordinate 2.5 Ga, 1.89–1.78 Ga, 980–950 Ma, 630–540 Ma and 430 Ma populations, indicating nearby sources including the early Neoproterozoic Sibao orogen, inverted Neoproterozoic rift basins and related plutons, recycled Ediacaran–Cambrian strata and, increasing with time, exposed Cathaysia basement and minor syn- to late-orogenic plutonic intrusions. The Devonian post-orogenic sandstones exhibit a dominant 440 Ma population with minor 2.5 Ga, 1.89–1.78 Ga, 860–780 Ma and 630–540 Ma populations, suggesting a dominant contribution from now widely exposed, mid- to late-orogenic plutonic intrusions (with or without contributions from rare volcanism of similar ages) in a residual topographic high SE of the Lizhu-Changshan fault. This residual topographic high of the Wuyi-Yunkai orogen had completely perished by early Carboniferous time, c. 60Myr after the end of the orogenic event.

Field-based mapping, sandstone petrology, palaeocurrent measurements and zircon cathodoluminescence images, as well as detrital zircon U–Pb geochronology were integrated to investigate the provenance of the Upper Carboniferous – Upper Triassic sedimentary rocks from the northern Bogda Mountains, and further to constrain their tectonic evolution. Variations in sandstone composition suggest that the Upper Carboniferous – Lower Triassic sediments displayed less sedimentary recycling than the Middle–Upper Triassic sediments. U–Pb isotopic dating using the LA-ICP-MS method on zircons from 12 sandstones exhibited similar zircon U–Pb age distribution patterns with major age groups at 360–320 Ma and 320–300 Ma, and with some grains giving ages of > 541 Ma, 541–360 Ma, 300–250 Ma and 250–200 Ma. Coupled with the compiled palaeocurrent data, the predominant sources were the Late Carboniferous volcanic rocks of the North Tianshan and Palaeozoic magmatic rocks of the Yili–Central Tianshan. There was also input from the Bogda Mountains in Middle–Late Triassic time. The comprehensive geological evidence indicates that the Upper Carboniferous – Lower Permian strata were probably deposited in an extensional context which was related to a rift or post-collision rather than arc-related setting. Conspicuously, the large range of U–Pb ages of the detrital zircons, increased sedimentary lithic fragments, fluvial deposits and contemporaneous Triassic zircon ages argue for a Middle–Late Triassic orogenic movement, which was considered to be the initial uplift of the Bogda Mountains.

Silicified beyrichiocopid and podocopid ostracods from limestone nodules derived from the middle part of the Ichinotani Formation within the Hida Gaien Terrane of central Honshu Island, Japan, are associated with fusulinid foraminifera that indicate strata of the middle Moscovian (Pennsylvanian, Carboniferous). This is a rare record of ostracods from the Palaeozoic of Japan and the first systematic description of ostracods from the Carboniferous of the Hida Gaien Terrane. The fauna comprises six ostracod species (two new) assigned to the generaAmphissites,Kirkbya,Bairdia,AechminaandHealdia, and additional material of possible cavellinids. The numerical dominance of ornamented beyrichiocopids such asKirkbyaandAmphissites, along with smaller numbers of smooth podocopids such asBairdia, indicates an ‘Eifelian mega-assemblage’ ecotype (sensuG. Becker), that is typical of mid Palaeozoic shallow marine, high-energy environments in a fore-reef ecosystem.

The Collserola Range includes a representative stratigraphic succession of the Palaeozoic of the central part of the Catalan Coastal Ranges, ranging from Cambro-Ordovician to Carboniferous times. In this paper we present an up-to-date review of the stratigraphy and structure of the Palaeozoic of the Collserola Range, and provide geochemical and Sm–Nd isotope data to constrain the pre-Mesozoic crustal evolution of this sector of the Variscan Belt. Geochemical compositions indicate that the Palaeozoic siliciclastic rocks of the Collserola Range were fed by a relatively mature heterogeneous source of sediment, comprising quartz-rich sediments to intermediate igneous rocks. The siliciclastic rocks of the Collserola Range show great geochemical affinity with the turbidites of passive margins. The Sm–Nd signature of the siliciclastic rocks is compatible with those of the Palaeozoic and late Proterozoic fine-grained siliciclastic rocks of the neighbouring terrains of SW Europe. There is a small decrease of the εNdT with decreasing age of sedimentation from the Cambro-Ordovician to the Carboniferous, suggesting an increase of the amount of more ‘juvenile’ material. The presence of small volumes of alkaline basaltic rocks provides evidence for the input of juvenile material in the early Palaeozoic basin and suggests that an extensional tectonic regime prevailed during the Cambro-Ordovician sedimentation. From a geodynamic point of view, the overall analysis of the data implies that the Palaeozoic rocks of the Catalan Coastal Ranges were part of the Northern Gondwana passive margin before the closure of the Rheic Ocean and the subsequent Variscan Orogeny.

Flysch-type, syn-orogenic deposits of Carboniferous age occur in relation to the emplacement of a large allochthonous nappe stack in the Variscan belt of NW Iberia. New U–Pb age populations of detrital zircons obtained using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) are considered together with others from previously dated samples to establish the relationships between sedimentation and thrusting. The age populations of four syn-orogenic formations are compared with those of the pre-orogenic sequence in the Autochthon and Parautochthon, representing the Gondwanan passive margin, and in the Allochthon, formed by peri-Gondwanan and oceanic terranes. In addition, a new structural study has been carried out to understand the relationships between the syn-orogenic deposits and the development of Variscan structures. The aims are to identify the sources of sediments and to establish the relationship between Variscan structural evolution and syn-orogenic sedimentation. Development of a forebulge outwards from the allochthonous front, deduced from the structural study, suggests the existence of depocentres that hosted the syn-orogenic sediments. Together with the trend shown by the more recent zircons in each formation, that are younger towards the external zones, the data suggest that sedimentation occurred in progressively migrating depocentres formed in front of the allochthonous wedge during its emplacement. The zircon age populations point to the Allochthon as the main source of detritus for the syn-orogenic basins, with perhaps a limited participation of the Parautochthon and Autochthon in the younger formations.

Two stratigraphic sections spanning the mid-Carboniferous boundary were examined in the Clare Shale Formation of the Shannon Basin in Western Ireland. Calcareous nodules intermittently occur within these generally non-calcareous organic-rich shales, and these have yielded Serpukhovian and Bashkirian conodont elements. The biostratigraphic range of the Irish material is illustrated here for the first time. Results show that the mid-Carboniferous and Arnsbergian–Chokierian boundaries are coincident at Ballybunion.Gnathodus girtyiis restricted to the lower part of the Serpukhovian Stage (Late Mississippian), whileG. bilineatus bollandensispersists into much younger strata, close to the first occurrence ofDeclinognathodus noduliferus s.l. One element belonging toG. postbilineatusis also present. These findings support the argument thatD. noduliferus s.l. developed fromG. b. bollandensis, rather than fromG. girtyi. The biostratigraphical tool for the identification of the mid-Carboniferous boundary globally, and the suitability of the section at Arrow Canyon, USA as a GSSP, may therefore need to be reassessed.

Stigmaria is one of the iconic plant fossils of the Carboniferous and fragments of the narrower parts of the rhizomorph are found in most museum collections. However, very few almost entire specimens have been found and preserved. A new specimen of Stigmaria from Brymbo, North Wales is described and compared with other preserved examples from Europe and North America. The Brymbo specimen shows a large portion of trunk still attached to the large stigmarian base, which is a rare find, and this specimen supports our ideas of how these impressively large casts were formed. Stigmarias were preserved by the deposition of minerals around them following a sediment inundation, which gave sufficient support while the tissues rotted and filled with sediments. Remnants of the outer tissues were compressed to form a thin surrounding coal layer.

The Carboniferous-Triassic Trinity Peninsula Group is a metasedimentary sequence that crops out widely in the northern Antarctic Peninsula. These are some of the most extensive outcrops in the area and hold the key to evaluating the connections of the Antarctic Peninsula in Gondwana; however, they are still poorly understood. Here we present our provenance study of the Trinity Peninsula Group using petrographic and geochemical approaches in combination with cathodoluminescence of detrital quartz in order to constrain its source characteristics and tectonic setting. Using differences in modal composition and quartz cathodoluminescence characteristics, we define three petrofacies derived from the progressive uplift and erosion of a volcano-plutonic continental arc, which exposed the plutonic-metamorphic roots. As indicated by major and trace elements, the source is felsic with a composition ranging from tonalitic to granodioritic. The relatively unweathered condition of the source area points to a dry and cold climate at the time of deposition, but this does not necessarily mean that it was glaciated. Deposition of the sediments occurred within an active continental margin, relatively close to the source area, probably along the south Patagonia–Antarctic Peninsula sector of Gondwana. Strong chronological, petrological and chemical similarities with the sediments of the Duque the York Complex in Patagonia suggest that they were derived from the same source.

The uppermost Famennian – lowermost Tournaisian interval has been analysed in detail using biostratigraphy, sedimentology, magnetic susceptibility and geochemistry in a reference section of the relatively shallow carbonate ramp environment within the Pomeranian Basin. High-resolution biostratigraphic study, based on miospores, allows recognition of the standard western European lepidophyta–nitidus (LN) and verrucosus–incohatus (VI) zones, as well as the Convolutispora major Zone, a local Pomeranian equivalent of the European standard hibernicus–distinctus (HD) Zone. The sedimentary succession and specific phenomena recognized close to the Devonian/Carboniferous boundary, such as fluctuations in water column euxinia, wildfire evidence, relative sea-level changes and perturbations of the carbon cycle reflected by positive carbon excursions, display a pattern partly similar to that observed in many areas in Europe during the Hangenberg Event, although the Hangenberg Black Shale horizon is not developed here. These important microscale environmental perturbations were observed not only within the Famennian LN miospore Zone but in a wide interval between the LN and the lowermost local Convolutispora major miospore zones ( = lower part of HD standard miospore Zone). It is still uncertain whether the recognized event(s) were connected solely with the Hangenberg Event, which was possibly complex and multi-phased as is sometimes suggested, or whether they represent a succession of regionally limited, post-Hangenberg events. This question needs to be further investigated on broader stratigraphic and geographical scales.

The Palaeozoic rocks of the Dingle Peninsula provide a record of the evolution of the Caledonides, Acadides and Variscides. The succession ranges from Early Ordovician deep-water sediments, through Silurian shallow marine to non-marine sediments and volcanic rocks to an Old Red Sandstone (ORS) succession topped by Carboniferous marine shales. Comparison of structural styles in the unconformity-bounded groups, together with a detailed analysis of fault zones, allows the tectonic history to be deduced. The older rocks record Caledonian processes on the margin of Avalonia during Early Ordovician time and convergence then soft collision with Laurentia during Silurian time. The Dingle Basin was developed during the late Silurian – Early Devonian transtension in the Iapetus suture zone and was inverted in the latest Emsian Acadian orogenic episode. Post-Dingle Group ORS groups in the north of the peninsula were deposited in a syn-rift footwall block to the main Munster Basin. The Acadian transpressional and Munster Basin extensional structures were reactivated or overprinted in the Variscan deformation such that Acadian folds are transected by Variscan cleavage in both plan and vertical views. After Iapetus closure, changes in the tectonic regime are believed to be a result of adjustments in the geometry of subduction of the Rheic Ocean.

U–Pb and Lu–Hf isotope analyses of detrital zircon from the latest Ordovician (Hirnantian) Langøyene Formation, the Late Silurian Ringerike Group and the Late Carboniferous Asker Group in the Oslo Rift were obtained by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Overall the U–Pb dating yielded ages within the range 2861–313 Ma. The U–Pb age and Lu–Hf isotopic signatures correspond to virtually all known events of crustal evolution in Fennoscandia, as well as synorogenic intrusions from the Norwegian Caledonides. Such temporally and geographically diverse source areas likely reflect multiple episodes of sediment recycling in Fennoscandia, and highlights the intrinsic problem of using zircon as a tracer-mineral in ‘source to sink’ sedimentary provenance studies. In addition to its mostly Fennoscandia-derived detritus, the Asker Group also have zircon grains of Late Devonian – Late Carboniferous age. Since no rocks of these ages are known in Fennoscandia, these zircons are inferred to be derived from the Variscan Orogen of central Europe. The final version of this research has been published in Geological Magazine. © 2014 Cambridge University Press

The uninterrupted succession of the Mississippian–Pennsylvanian boundary beds in the Muradymovo section in the South Urals contains diverse fossils and has a high correlative potential. The Muradymovo section is located in the Zilair Megasynclinorium (ZM), which belongs to the West Uralian Subregion and displays carbonate-siliciclastic deep-water facies of the Bukharcha Formation, which is partly Serpukhovian (Kosogorian, Protvian and Yuldybaevian) and partly Bashkirian (Syuranian). In the southern ZM, the lower part of the formation contains argillaceous carbonates with beds of shale and siltstone, subordinate clastic limestones and limestone breccia, while the upper part is mostly limestone with cherty interbeds. In the north of the ZM, the formation mainly consists of limestone. The Muradymovo succession contains no identifiable gaps in the Mid-Carboniferous Boundary (MCB) portion and has a succession of foraminiferal, conodont, ammonoid and ostracod zones. The MCB in this section coincides with the base of the Bogdanovkian and is defined by the entry ofDeclinognathodus noduliferus.This level falls within the upper part of the foraminiferalMonotaxinoides transitoriusZone, is near the base of the ammonoidHomoceras–HudsonocerasGenozone and can be correlated worldwide.

The Tournaisian and Viséan were formerly considered as series and in Belgium were divided into two (Hastarian and Ivorian) and three stages (Moliniacian, Livian and Warnantian), which are now considered as substages. The Belgian substages are based on conodonts and foraminifers, and incidentally on rugose corals, and are described here. Their boundaries, biostratigraphy and sequence stratigraphy are well detailed and clearly defined. The base of the Hastarian (lower Tournaisian) corresponds to the base of the Tournaisian (base of Carboniferous); the base of the Ivorian (upper Tournaisian) corresponds to the appearance of the conodont Polygnathus communis carina, a little above the last Siphonodella; the base of the Moliniacian (lower Viséan) corresponds to the base of the Viséan stage defined by the first occurrence of the foraminifer Eoparastaffella simplex; the Livian (middle Viséan) corresponds to the foraminiferal MFZ12 Zone and is marked by the appearance of Koskinotextularia and Pojarkovella nibelis; the base of the Warnantian (upper Viséan) is marked by the appearance of Neoarchaediscus, Vissariotaxis, Planospirodiscus, and Palaeotextularia with a bilaminar wall, the index taxa of the MFZ13-Neoarchaediscus Zone. The up-to-date chronostratigraphic subdivision of the Tournaisian and Viséan is not limited to Belgium and the surrounding areas. It can be applied through Eurasia as far as South China. The Belgian units could therefore be the basis for a future international division of the Tournaisian into two parts (Hastarian and Ivorian) and of the Viséan into three parts (Moliniacian, Livian and Warnantian), corresponding to time intervals of c. 5–8 Ma.

The Task Group charged with proposing the GSSP for the base of the Serpukhovian Stage (Mississippian, Lower Carboniferous) is likely to use the global First Appearance Datum (FAD) of the conodontLochriea ziegleriin the lineageLochriea nodosa–L.zieglerifor the definition and correlation of the base of the stage. It is important to establish that the FAD ofL.ziegleriin different basins is penecontemporaneous. Ammonoids provide high-resolution biostratigraphy in the Late Mississippian but their use in international correlation is limited by provincialism. However, it is possible to assess the levels of diachronism of the First Occurrence Datum (FOD) ofL.ziegleriin sections in NW Europe using ammonoid zones. Published conodont distribution in the Rhenish Slate Mountains of Germany show the FOD ofL.ziegleriin theEmstites novalisBiozone (upper part of the P2czone of the UK and Ireland) butL.zieglerihas also been reported as occurring in theNeoglyphioceras spiraleBiozone (P1dzone). In the Yoredale Group of northern England, the FOD ofL.ziegleriis in either the P1cor P1dzone. In NW Ireland, the oldest records of bothL.nodosaandL.ziegleriare from theLusitanoceras granosumBiozone (P2a). Although there is some discrepancy in the recorded levels of the FOD ofL.ziegleriin NW Europe, this may be as a result of collection failure. The base of the Serpukhovian based on the FAD ofLochriea ziegleriwill be in the middle of the Brigantian regional Substage.

A preliminary summary of the lower Visean to uppermost Moscovian (Carboniferous) conodont succession and biostratigraphy of the Dianzishang section in Zhenning, Guizhou, South China is presented. Eleven conodont zones, in ascending order, can be recognized:Gnathodus praebilineatus,Gnathodus bilineatus,Lochriea ziegleri,Declinognathodus noduliferus,Neognathodus symmetricus, ‘Streptognathodus’expansus(primitive form), ‘Streptognathodus’expansus,Mesogondolella donbassica – Mesogondolella clarki,Idiognathodus podolskensis,Swadelinafauna andIdiognathodus swadeizones. The first occurrences ofLochriea ziegleriat the base of the Serpukhovian Stage,Declinognathodus noduliferus noduliferusat the base of the Bashkirian Stage and ‘Streptognathodus’expansusat the base of the Moscovian Stage are recognized. The definitions of these stage boundaries, as well as that of the base of the Kasimovian Stage are discussed. Correlations with the Naqing section in South China, Russian and North American sections, as well as other important sections in the world, are considered.