Abstract The Carboniferous chronostratigraphic scale consists of two subsystems, six series and seven stages. Precise numerical age control within the Carboniferous is uneven, and a global magnetic polarity timescale for the Carboniferous is far from established. Isotope stratigraphy based on Sr, C and O isotopes is at an early stage but has already identified a few Sr and C isotope events of use to global correlation. Cyclostratigraphy has created a workable astrochronology for part of Pennsylvanian time that needs better calibration. Chronostratigraphic definitions of most of the seven Carboniferous stages remain unfinished. Future research on the Carboniferous timescale should focus on Global Stratotype Section and Point (GSSP) selection for the remaining, undefined stage bases, definition and characterization of substages, and further development and integration of the Carboniferous chronostratigraphic scale with radioisotopic, magnetostratigraphic, chemostratigraphic and cyclostratigraphic tools for calibration and correlation, and the cross-correlation of non-marine and marine chronologies.

Abstract The Carboniferous chronostratigraphic scale is a hierarchy of two subsystems, six series and seven stages developed during nearly two centuries of research. Carboniferous stage nomenclature developed with the proposal of numerous regional stages/substages based primarily on palaeobotanical, foraminiferal and ammonoid biostratigraphy, especially in Western Europe, the former Soviet Union, China and the USA. From the regional stages, seven ‘global stages’ have been identified (in ascending order): Tournaisian, Visean, Serpukhovian, Bashkirian, Moscovian, Kasimovian and Gzhelian. Three of the four ratified Carboniferous GSSPs use conodont evolutionary events as the primary signal for correlation – bases of Tournaisian, Bashkirian and base of Asselian. The GSSP of the Visean base has a foraminiferal event as its primary signal. Issues in the development of a Carboniferous chronostratigraphic scale include the rank of chronostratigraphic units, provinciality, conodont biostratigraphy, palaeobotanical biostratigraphy and the development of astrochronology and other methods of chronology and correlation.

Abstract Several existing schemes for Carboniferous stratigraphy officially adopted in regions of the Russian Federation are summarized and discussed. These regions with different geological histories and distinct depositional settings include the Moscow Basin, the Urals, North Timan, Siberia, the Kuznetsk Basin and the Mongol–Okhotsk, Verkhoyansk–Okhotsk and Kolyma–Omolon regions. Broad correlations based on macro- and microfossils are possible between the regions, while all regional schemes are correlated to the official Russian General Stratigraphic Scheme for the Carboniferous, using zonations based on orthostratigraphic fossils. The Russian General Stratigraphic Scheme is correlated to the International Stratigraphic Scale using ammonoids, conodonts, foraminifers and palynomorphs.

Abstract The western Andean belt of Argentina displays a comprehensive record of the Carboniferous and earliest Permian rocks so extensive that it allows an exceptional reconstruction of the Late Paleozoic Ice Age of the southwestern margin of the South American Gondwana area. Severe endemism of the Gondwana biota during this period makes it difficult to achieve a precise correlation of these glacially influenced deposits with the coeval sequences of the palaeoequatorial belt, where the subdivisions of the International Chronostratigraphic Chart (ICC) are currently defined. The abundant palaeontological record available from the Upper Paleozoic deposits of central-western Argentina, central Patagonia and eastern Argentina makes it possible to recognize five successive faunal stages that allow a proper ordering of the sequences of this period. The proposed regional stages, and their assumed chronological position regarding the standards of the current ICC, are: the Malimanian (late Tournaisian), Barrealian (Mid-Carboniferous or Serpukhovian–Bashkirian), Aguanegrian (Upper Pennsylvanian), Uspallatian (Asselian–Tastubian?) and Bonetian (Sakmarian). This paper aims to reiterate former recommendations about the convenience of having regional reference units and suggests the consideration of the available faunal stages as possible chronostratigraphic subdivisions for the Carboniferous–early Permian of the southeastern margin of Gondwana.

Abstract The geomagnetic polarity pattern for the Carboniferous is incompletely known with the best-resolved parts in the Serpukhovian and Bashkirian. Hence, data from both igneous and sedimentary units are also used in an additional polarity bias evaluation. In the Tournaisian to mid Visean interval polarity is mainly derived from palaeopole-type palaeomagnetic studies, allowing identification of polarity bias chrons. Seven polarity bias chrons exist in the Mississippian (MI1n B to MI4n B ) with an additional 33 conventional magnetochrons and submagnetochrons (MI4r to MI9r). The Moscovian and Gzhelian polarity is best resolved in magnetostratigraphic studies from the Donets Basin and the southern Urals. Dispute about the reliability of these data is ill-founded, since an assessment of supporting data from palaeopole-type studies suggests that these datasets currently provide the best magnetic polarity data through the Pennsylvanian. Polarity bias assessment indicates a normal polarity bias zone in the Kasimovian. In the Pennsylvanian there are 27 conventional magnetochrons and submagnetochrons (PE1n to CI1r) and one normal polarity bias chron (PE8n B ). The Kiaman Superchron begins in the mid Bashkirian, with clear data indicating brief normal polarity submagnetochrons within the Superchron. The magnetochron timescale is calibrated using 31 U–Pb zircon dates and a quantitative Bayesian-based age-scaling procedure.

Abstract We present an updated set of Carboniferous Sr, C and O isotope stratigraphies based on the existing literature, given the importance of chemostratigraphy for stratigraphic correlation in the Carboniferous. The Carboniferous 87 Sr/ 86 Sr record, constructed using brachiopods and conodonts, exhibits five first-order phases beginning with a rapid decline from a peak value of c. 0.70840 at the Devonian–Carboniferous boundary to a trough (0.70776–0.70771) in the Visean followed by a rise to a plateau ( c. 0.70827) in the upper Bashkirian. A decline to c. 0.70804 follows from the lowermost Gzhelian to the close of the Carboniferous. Contemporaneous carbonate δ 13 C records exhibit considerable variability between materials analysed and by region, although pronounced excursions (e.g. the mid-Tournaisian positive excursion and the end-Kasimovian negative excursion) are present in most records. Bulk carbonate δ 13 C records from South China and Europe, however, are generally consistent with those of brachiopod calcite from North America in terms of both absolute values and trends. Both brachiopod calcite and conodont phosphate δ 18 O document large regional variability, confirming that Carboniferous δ 18 O records are invalid for precise stratigraphic correlation. Nevertheless, significant positive δ 18 O shifts in certain intervals (e.g. mid-Tournaisian and the Mississippian–Pennsylvanian transition) can be used for global correlation.

Abstract Icehouses are the less common climate state on Earth, and thus it is notable that the longest-lived ( c. 370 to 260 Ma) and possibly most extensive and intense of icehouse periods spanned the Carboniferous Period. Mid- to high-latitude glaciogenic deposits reveal a dynamic glaciation–deglaciation history with ice waxing and waning from multiple ice centres and possible transcontinental ice sheets during the apex of glaciation. New high-precision U–Pb ages confirm a hypothesized west-to-east progression of glaciation through the icehouse, but reveal that its demise occurred as a series of synchronous and widespread deglaciations. The dynamic glaciation history, along with repeated perturbations to Earth System components, are archived in the low-latitude stratigraphic record, revealing similarities to the Cenozoic icehouse. Further assessing the phasing between climate, oceanographic, and biotic changes during the icehouse requires additional chronostratigraphic constraints. Astrochronology permits the deciphering of time, at high resolution, in the late Paleozoic record as has been demonstrated in deep- and quiet-water deposits. Rigorous testing for astronomical forcing in low-latitude cyclothemic successions, which have a direct link to higher-latitude glaciogenic records through inferred glacioeustasy, however, will require a comprehensive approach that integrates new techniques with further optimization and additional independent age constraints given challenges associated with shallow-marine to terrestrial records.

Abstract The Carboniferous Foraminifera are composed of representatives of three classes: Fusulinata, Miliolata and Nodosariata. Despite ample literature on Paleozoic Allogromiata and Textulariata, the real presence of these classes remains questionable during the Carboniferous and they are thus excluded herein. The main biostratigraphical markers belong to the superfamilies Archaediscoidea, Lasiodiscoidea and Bradyinoidea, even if many genera among the archaediscoids still have a controversial nomenclature, as well as do some lasiodiscids and bradyinoids. Secondary biostratigraphical markers belong to Lituotubelloidea (= ‘Tournayelloidea’ of the authors), Endothyroidea and Loeblichioidea (these latter giving rise to the primitive Fusulinida). The Miliolata appear at the Visean/Serpukhovian boundary interval. The typical Carboniferous miliolates are primitive nubeculariins and cornuspirinins. Tubiphytids might be miliolate and cyanobacterium consortia, derived from the nubeculariin Palaeonubecularia . The most primitive nodosariates (syzraniids) appeared in the Moscovian; and gave rise, in the latest Carboniferous, to Protonodosaria , Nodosinelloides and possibly Polarisella , Paravervilleina and the oldest Geinitzinoidea. Palaeobiological data are mainly provided by the genera Bradyina , Tetrataxis and Climacammina . Palaeobiogeographical distributions of Pojarkovella , Janischewskina, Eosigmoilina , Brenckleina , Spireitlina , Hemigordius and Syzrania testify to the successive foraminiferal migrations between the Palaeotethys, Ural and Panthalassan oceans. Two taxa are created: Eoparastaffellidae and Banffellinae.

Abstract This paper proposes a synthesis of the taxonomy, phylogeny, palaeogeographic distribution, regional biostratigraphy, and palaeobiogeographic faunal development of Carboniferous fusuline foraminifers. They appeared in the latest Tournaisian and comprised a small-sized, morphologically conservative taxonomic group during the Mississippian. Fusulines became larger and prevailed in Pennsylvanian foraminiferal assemblages. Carboniferous fusulines consist of Ozawainellidae, Staffellidae, Schubertellidae, Fusulinidae, and Schwagerinidae, in which 95 genera are considered as valid taxonomically. Upsizing their shells throughout the Pennsylvanian is likely related to symbiosis with photosynthetic microorganisms, which was accelerated by the acquisition of a keriothecal wall in Late Pennsylvanian schwagerinids. Regional fusuline succession data from 40 provinces provide a refined biostratigraphy, enabling zonation and correlation with substage- or higher-resolution precision in the Pennsylvanian. Their spatio-temporal faunal characteristics show that fusulines had a cosmopolitan palaeobiogeographic signature in Mississippian time, suggesting unrestricted faunal exchange through the palaeoequatorial Rheic Ocean. After the formation of Pangaea, Pennsylvanian fusulines started to show provincialism, and their distributions defined the Ural–Arctic Region in the Boreal Realm, Palaeotethys, Panthalassa, and North American Craton regions in the Palaeoequatorial Realm, and Western Gondwana and Eastern Peri-Gondwana regions in the Gondwana Realm. The Western Palaeotethys and East European Platform Subregions maintained higher generic diversity throughout the Pennsylvanian.

Abstract We present an updated look at Carboniferous brachiopod biozonation from most of the world framed into a revised Carboniferous palaeogeography, based on a selection of the literature published on Carboniferous brachiopods since the nineteenth century. The biostratigraphic significance of the most important brachiopod taxa is synthesized in seven geographical correlations. The Mississippian is characterized by rich brachiopod faunas, with widespread taxa with a good potential for global correlation, such as Rugosochonetes , Delepinea , Buxtonia , Antiquatonia , Spinocarinifera , Marginatia , Fluctuaria , Ovatia , Rhipidomella , Lamellosathyris , Unispirifer , Tylothyris and Syringothyris . From the mid-Visean to the late Serpukhovian, taxa of gigantoproductidines are biostratigraphically significant, and occur everywhere except South America and Australia, which remain as distinct faunal successions for most of the period. A major turnover occurs at the beginning of the Pennsylvanian, characterized by a higher degree of provincialism. Pennsylvanian brachiopod faunas are diverse in China, Russia and North America, but otherwise they are less developed and are characterized mostly by endemic taxa, hampering long-distance correlation. An exception is the rapid diversification of taxa of the Choristitinae, which were widespread from the Bashkirian to the Moscovian, allowing long-distance correlation.

Abstract During the Carboniferous, crinoids were commonly so abundant that their skeletal ossicles formed limestones termed encrinites. Major evolutionary changes occurred within the Camerata and Articuliformes, as the former were displaced by the latter as the dominant clade. Both the Mississippian and the Pennsylvanian subperiods started with high evolutionary rates and ended with low evolutionary rates associated with glaciation. Although not typically used for biostratigraphy, crown-based crinoid genera can be used as biostratigraphic indicators for Carboniferous stages. Paleozoic crinoid biodiversity reached its maximum during the Carboniferous, from which there are numerous well-documented localities with high biodiversity. Faunas from the palaeobiogeographical regions of Laurussia, Palaeo-Tethys and Gondwana are reviewed. For Mississippian crinoids, 37 genera are designated as biostratigraphically useful; and, for the Pennsylvanian, 44 genera are identified. Recognition of the utility of these genera for biostratigraphy is important for dating crinoid deposits, which may be devoid of other biostratigraphically useful fossils, and add to our overall ability to delineate the temporal resolution of life on Earth.

Abstract Rugose corals are one of the major fossil groups in shallow-water environments. They played an important role in dividing and correlating Carboniferous strata during the last century, when regional biostratigraphic schemes were established, and may be useful for long-distance correlation. Carboniferous rugose corals document two evolutionary events. One is the Tournaisian recovery event, with abundant occurrences of typical Carboniferous rugose corals such as columellate taxa and a significant diversification of large, dissepimented corals. The other is the changeover of rugose coral composition at the mid-Carboniferous boundary, which is represented by the disappearance of many large dissepimented taxa with complex axial structures and the appearance of typical Pennsylvanian taxa characterized by compound rugose taxa. The biostratigraphic scales for rugose corals show a finer temporal resolution in the Mississippian than in the Pennsylvanian, which was probably caused by the Late Paleozoic Ice Age that resulted in glacial–eustatic changes and a lack of continuous Pennsylvanian carbonate strata. The Pennsylvanian rugose corals are totally missing in the Cimmerian Continent. High-resolution biostratigraphy of rugose corals has so far only been achieved in few regions for the Mississippian timescale. In most regions, more detailed taxonomic work and precise correlations between different fossil groups are needed.

Abstract Considerable progress has been made by international teams in refining the traditional ammonoid zonation that remains the backbone of Carboniferous stratigraphy. The Carboniferous ammonoid genozones, with a few gaps, are now recognized throughout the entire system in most successions worldwide. Refined collecting and documentation of occurrences in Western Europe, North Africa, the Urals, China and North America aimed to establish the first evolutionary occurrences, and facilitated correlation with foraminiferal and conodont scales for most of the Carboniferous. From ten to eleven ammonoid genozones are now recognized in the Mississippian, and eight to nine genozones in the Pennsylvanian. Of these, the established lower boundaries of the subsystems are reasonably well correlated with the ammonoid zonation, whereas correlations with the ratified foraminiferal-based lower boundary of the Visean and other stage boundaries, currently under discussion, need further research. Future success in the ammonoid geochronology will also depend on accurate identification and re-illustration of the type material, including material described by pioneers of ammonoid biostratigraphy.

Abstract Carboniferous conodont biostratigraphy comprises regional zonations that reflect the palaeogeographical distribution of taxa and distinct shallow-water and deep-water conodont biofacies. Some species have a global distribution and can effect high quality correlations. These taxa are incorporated into definitions of global Carboniferous chronostratigraphic units. A standard global Carboniferous zonation has not been developed. The lowermost Mississippian is zoned by Siphonodella species, excepet in shallow-water facies, where other polygnathids are used. Gnathodus species radiated during the Tournaisian and are used to define many Mississippian zones. A late Tournaisian maximum in diversity, characterized by short-lived genera, was followed by lower diversity faunas of Gnathodus species and carminate genera through the Visean and Serpukhovian. By the late Visean and Serpukhovian, Lochriea provides better biostratigraphic resolution. Shallow-water zonations based on Cavusgnathus and Mestognathus are difficult to correlate. An extinction event near the base of the Pennsylvanian was followed by the appearance of new gnathodid genera: Rhachistognathus , Declinognathodus , Neognathodus , Idiognathoides and Idiognathodus . By the middle of the Moscovian, few genera remained: Idiognathodus , Neognathodus and Swadelina. During the middle Kasimovian and Gzhelian, only Idiognathodus and Streptognathodus species were common. Near the end of the Gzhelian, a rediversification of Streptognathodus species extended into the Cisuralian.

Abstract Among several groups of fishes existing in the Carboniferous, the Chondrichthyes appear to have the greatest stratigraphic potential. However, despite the long history of investigation into Paleozoic sharks, and especially their teeth, our knowledge of their usefulness in biostratigraphy and palaeoecology is still at an early stage of development. This is mainly because for a long time palaeoichthyologists have been focused on descriptions of individual taxa, and not on documenting whole assemblages. The microscopic teeth of pelagic stem-group Chondrichthyes, such as Thrinacodus (Phoebodontiformes), Denaea and Stethacanthulus (Falcatidae, Symmoriiformes) appear to be more useful than macrofossils (e.g. tooth plates of Holocephali) because of their wider geographical distribution and weaker facies dependence.

Abstract This paper presents a summary of palynological data for Pennsylvanian age coal beds in the Appalachian Basin, discussed primarily from a biostratigraphic perspective. Coal bed palynofloras of Lower Pennsylvanian through early Permian age are compared and correlated with miospore assemblage zones established for western Europe, and the Eastern Interior (Illinois) and Western Interior Basins of the mid-continent USA. Lower Pennsylvanian palynofloras, which are dominated by lycopsid spores, are correlative with the Langsettian of western Europe and the Morrowan of the Eastern and Western Interior mid-continent USA Basins. Stratigraphically useful palynotaxa include Dictyotriletes bireticulatus , Radiizonates striatus , Schulzospora rara , Granasporites medius , Laevigatosporites minor and Endosporites globiformis . Middle Pennsylvanian palynofloras change through time, being lycopsid dominant in the lower part and more heterogeneous in the middle and upper parts with increased contributions from other Pennsylvanian plant groups. They are correlative with the Duckmantian, Bolsovian and Asturian of western Europe and the Atokan and Desmoinesian of the Eastern and Western Interior mid-continent USA Basins. Stratigraphically useful palynotaxa include Secarisporites remotus , Microreticulatisporites sulcatus , Vestispora fenestrata , Triquitrites sculptilis , Laevigatosporites globosus , Radiizonates difformis , Torispora securis , Triquitrites minutus , Mooreisporites inusitatus , Murospora kosankei , Thymospora pseudothiessenii and Schopfites dimorphus . Upper Pennsylvanian and lower Permian coal beds in the Appalachian Basin, in contrast to their Lower and Middle Pennsylvanian counterparts, are strongly dominated by tree fern spore palynotaxa. Palynofloras correlate with the Stephanian and Autunian of western Europe and the Missourian, Virgilian and Wolcampian of the Eastern and Western Interior mid-continent USA Basins.

Abstract In the Carboniferous, terrestrial vegetation became widespread, diverse and abundant. The resulting fossil record has proved to be an effective biostratigraphic tool for intra- and interbasinal correlations. Besides palaeogeographical configurations, Carboniferous plant biostratigraphy is affected by a transition from greenhouse conditions during most of the Mississippian to an icehouse climate in the Pennsylvanian. The greenhouse Mississippian climate resulted in weak provincialism, with a cosmopolitan flora ranging from the tropics to middle latitudes. The global cooling around the Mississippian–Pennsylvanian boundary enhanced development of a latitudinal climatic zonation and related floral provincialism. These changes are expressed in the recognition of distinct realms or kingdoms, where the tropical Amerosinian Realm (or Euramerican and Cathaysian realms) is surrounded by the Angaran and Gondwanan realms occupying middle to high latitudes of the northern and southern hemispheres, respectively. Floristic endemism in the Pennsylvanian precludes development of a global macrofloral biostratigraphy. Instead, each realm or area has its own biostratigraphic scheme. Poorer and less diverse floras of the Gondwanan and Angaran realms resulted in the establishment of relatively low-resolution macrofloral biostratigraphic schemes. Higher-resolution macrofloral zonations exist only in the tropical Amerosinian Realm due to diverse and abundant floras dominated by free-sporing and early seed plants occupying extensive wetlands.

Abstract For the biostratigraphy of mixed continental-marine and purely continental sections in the palaeotropical belt of Euramerica, 9 insect and 8 conchostracan zones are newly defined or improved. These zones encompass the time interval from the Early Pennsylvanian (middle Bashkirian) up into the early Permian (early Asselian) of the Euramercian biotic province. They are linked as much as possible to the marine Standard Global Chronostrigraphic Scale by common occurrences of insects and/or conchostracans with conodonts in mixed marine-continental sections as well as by the thus far available and reliable radioisotopic ages of associated volcanic rocks. This insect and conchostracan zonation is an alternative tool to the well-established macro-plant biostratigraphy of the Pennsylvanian. In contrast to the latter, only single specimens of insects or conchostracans, even if more rare than plant remains, allow biostratigraphic dating with a similar high temporal resolution.