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Abstract This paper explores microbially induced sedimentary structures (MISS) preserved in Late Paleozoic Ice Age deposits to evaluate the potential microbe-substrate physical interactions in ancient glacial settings. MISS have been recorded worldwide in different modern and ancient settings, mostly in tidal flats. However, their record in ancient glacial settings is still underrepresented. The reported MISS are preserved in the siltstone-claystone glacigenic rhythmites in Trombudo Central region of the Rio do Sul Formation (Paraná Basin, Pennsylvanian, southern Brazil). The recorded structures in these deposits are composed of wrinkle structures, dome structures, mat fragments, mat microfabrics, sinoidal structures, laminated leveling structures, oriented grains and mat-layer bound small grains, kinneyia structure, discoidal microbial colony, elongated filaments, and drab-haloed filaments. They represent the development of endobenthic and epibenthic microbial mats, as well as microbial earths. Endobenthic mat structures predominate in the siltstone beds, suggesting less time for development of microbial mat during deglaciation events and meltwater input. Epibenthic mat structures preserved in the claystone layers indicate episodic quiescence periods that allowed the mat achieve maturity and that cyanobacteria and sulfate-reducing bacteria composed a significant part of the microbial community. The set of MISS observed in the studied rhythmites have been commonly reported in tidal settings, and the presence of microbial earths structures indicate periods of drainage of the water bodies, at least partially. Thus, the microbial communities played an important role in ancient glacial settings during climatic amelioration periods, opening the colonization window for macroorganisms in outwash plains and marginal marine settings. This paper provides a characterization of different sorts of preserved MISS, and evaluate the physical interactions between microbial mats and the substrate, in the ancient glacigenic deposits from the Itararé Group. Highlights • Preserved MISS in glacigenic rhythmites of Pennsylvanian Paraná Basin in southern Brazil. • Preserved records represent the development of endobenthic and epibenthic microbial mats, as well as microbial earths. • The microbial communities enhancing the colonization window for macroorganisms during climatic amelioration periods. [ABSTRACT FROM AUTHOR]

Identifying ecological mechanisms that produce hierarchically arrayed spatial variation in community structure can be difficult in the fossil record due to conflation of spatial and temporal patterns. However, this difficulty can be mediated by minimizing the temporal duration of deposition within the unit examined. In this study, the fauna of the Upper Pennsylvanian Ames Limestone (Conemaugh Group) was analyzed to explore whether Ames paleocommunities exhibited hierarchical structure in a spatial dimension. This widespread carbonate unit was deposited during the maximum flooding interval of a glacio-eustatically influenced fifth order sea level cycle, and preserved taxa are contemporaneous within only a few thousand years. Paleocommunity structure and variability was assessed at multiple spatial scales using samples collected from seven outcrops of the Ames Limestone throughout southeastern Ohio which form a northeast to southwest trending transect parallel to the paleoshoreline. Abundance data were collected using quadrat sampling for brachiopods, bivalves, gastropods, bryozoa, corals, crinoids, echinoids, trilobites and foraminifera. Paleocommunity structure was analyzed via cluster, ordination, guild, and abundance analyses at multiple spatial scales (within a single locality, among localities and within the total study area) to provide insight on geographic partitioning of paleocommunity variation. Multiple levels of paleocommunity organization were recovered within the Ames fauna. All levels exhibited spatial partitioning, but the inferred proximate controls shifted from abiotic environmental controls at higher hierarchical levels to biotic controls at the lowest level. At the highest level, differentiation into a northern and southern regional paleocommunity was controlled primarily by substrate consistency and habitat heterogeneity related to variation in fluvial input within the basin. Local paleocommunity differentiation reflects biotic responses to topographic and environmental conditions that were geographically distributed within the region; whereas within outcrop variation was due largely to biotic feedback mechanisms. [ABSTRACT FROM AUTHOR]

Detached and coalified prepollen organs with huge monolete grains are reported for the first time from the Canadian Sydney Coalfield of Pennsylvanian age. Besides regarding these organs as Dolerotheca -like, the putative question is which medullosalean seed fern produced these organs? We investigated for the first time the physicochemistry of the prepollen to determine characteristic behavior under oxidative conditions, reporting results from solid- and liquid states infrared spectroscopy, liquid 1 H magnetic resonance, high precision liquid and pyrolytic-gas chromatography, and mass/charge ratios. The organs were tripartite, campanulate (bell-shaped) with lobate margins ca. 20 mm in diameter and ca. 30 mm long, and contained hundreds of elongate sporangia that were up to 8 mm long and filled with huge up to 833 μm long but probably juvenile Monoletes prepollen. These grains were covered by an acellular sporangial layer, which in turn, was covered by a cuticle bearing the imprint of near-isodiametric cells. The principal evidence for linking the Dolerotheca -like structure to foliar Alethopteris pseudograndinioides is shared occurrences of papillate cyclocytic stomata and trichomes, and the physical association of the alethopterid foliage and the prepollen organs. The physicochemical results point to diagenetic influence on the surface morphology and taxonomic parameters, refractory nature of the prepollen (as with extant pollen), and their aliphatic characteristics that are different from the aromatic extant pollen. [ABSTRACT FROM AUTHOR]

Tectonics and climate are the major extrinsic upstream controls on both the external and internal architectures of fluvial channels. While the role of tectonics has been well-documented, the role of climate has received less attention. Because both tectonics and climate can produce similar stratigraphic architectures, the ability to recognize and differentiate these has major ramifications for the interpretation of fluvial stratigraphy. The Pennsylvanian to Permian succession of the Maritimes Basin complex on Cape Breton Island is ca 5 km thick, and is composed of predominantly non-marine strata deposited within a series of depocentres characterized by different subsidence regimes. Basins in the west are transtensional depocentres characterized by episodic fault movement. In contrast, basins in the east were formed during prolonged periods of passive thermal subsidence. The stratigraphy is composed of four second-order sequences (A to D), each 5 to 10 Myr in duration. These sequences are composed of amalgamated fluvial channel deposits that fine upwards into extensive mud-dominated floodplain deposits with isolated fluvial channel bodies. A spectrum of fluvial styles is recorded within the study area including perennial, perennial/intermittent and ephemeral. Four stratigraphic intervals (E1 to E4) are recognized in which the deposits of strongly seasonal perennial/intermittent fluvial deposits are predominant. These intervals, 2 to 6 Myr in duration, are correlated across the study area between basins with differing tectonic regimes and do not correlate with a particular position in second-order sequences. This suggests that climate exerted the dominant influence on the formation of these intervals and can be differentiated from tectonic imprints. While the tectonic regime of a particular basin exerted a fundamental control on the external architecture, a coherent record of climate change is recognized in the internal architecture of fluvial units. This study demonstrates that tectonic and climatic controls can be recognized and differentiated in vertical successions by evaluating the changes in fluvial architecture. [ABSTRACT FROM AUTHOR]

Abstract: The medullosan pteridosperm Macroneuropteris scheuchzeri (Hoffmann) Cleal, Shute & Zodrow was widespread and abundant in the Middle to Late Pennsylvanian forests of tropical Pangaea. On the basis of its thick cuticles, few adaxial stomata, sunken stomata, and dense trichomes, it has been inferred to be a xeromorphic plant. Here we test that hypothesis by analyzing its facies distribution, especially in relation to coals, at 273 site collections from ~45 stratigraphic horizons accessioned in the Smithsonian National Museum of Natural History, Washington, D.C., U.S.A. The collections represent mostly (par)autochthonous assemblages and cover the taxon''s complete known temporal range west of the Appalachians in west-central Pangaea. Chi-square analysis of facies-occurrence data indicates that M. scheuchzeri had a strong preference for mineral-enriched wetlands that immediately preceded and followed the development of peat swamps and mires (coals), particularly during the late Middle Pennsylvanian (late Moscovian) times, coincident with a period of reduced polar ice volume. In the Late Pennsylvanian, following an interval of global warming and tropical wetland reorganization, palaeoequatorial climate shifted to an overall drier mode. This was accompanied by the disappearance of M. scheuchzeri from Europe and its limitation, west of the Appalachians, to the wettest available habitats on the landscape. Thus, our data falsify the hypothesis that M. scheuchzeri was a conventional xerophyte, but highlight the paradox of a plant with apparent xeromorphic features confined to a wetland habitat. We consider several possible explanations for this association: (1) response to nutrient deficiency, (2) response to substrate salinity (due to growth in coastal mangrove habitats), (3) response to the composition of the Palaeozoic atmosphere, (4) return on investment (long leaf lifespan), and (5) phylogenetic constraint reflecting ancestral conditions. Our findings have broader implications for interpreting a wide variety of other Pennsylvanian wetland plants, which similarly show ‘xermorphic’ features. [Copyright &y& Elsevier]

Abstract: Much of our far-field knowledge of glaciation and climate during the late Paleozoic ice age is built on decades of study of mixed carbonate–siliciclastic cyclothemic successions from paleotropical Euramerica. Far fewer carbonate-dominated successions have been studied despite their high sensitivity to changes in accommodation space and environmental conditions. Here we present a sequence stratigraphic framework for the carbonate-dominated Bird Spring Formation, southern Great Basin, U.S.A. and infer from it a relative sea-level history for the latest Mississippian through latest Pennsylvanian. Correlation of four successions across the paleo-platform documents changes in the lithofacies composition of meter-scale cycles, their cycle stacking patterns, and cycle bounding surfaces that record substantial variation in relative sea-level at several temporal scales during the Pennsylvanian. Ten genetic sequences bounded by intervals of restricted peritidal lithofacies, karst, terra rossa, rooted caliche and/or Protosols are recognized. Within sequences, 126 parasequences stack into parasequence sets that in turn define lowstand, transgressive and highstand systems tracts. The stratigraphic cycle stacking patterns and across-platform architecture of systems tracts suggest a mid-Carboniferous lowstand in relative sea level followed by a middle Morrowan (middle Bashkirian) highstand as previously suggested (Bishop et al., 2010). Subsequent progradation of the platform occurred during a gradual long-term fall through the late Morrowan and Atokan (late Bashkirian–early Moscovian), upon which repeated higher frequency events were superimposed, culminating in widespread exposure across the platform proximal to the Atokan–Desmoinesian boundary. Long-term sea level increased into the mid-Desmoinesian (end-Moscovian) after which progradation (late Desmoinesian) and aggradation (Missourian–Virgilian) of shallow-water and peritidal carbonates occurred across the Bird Spring platform. The progradational-to-aggradational phase involved an abrupt shift from ramp to rimmed shelf geometry in the Missourian (Kasimovian) likely in response to progressively increasing sea level, dampened high-frequency sea level fluctuations and/or to regional faulting along the Bird Spring platform margin. Inferred magnitudes of short-term (105 yr) fluctuations superimposed on the longer-term rises and falls range from 20 to >70m during the early to mid-Pennsylvanian and are substantially reduced (≤20m) during the late Pennsylvanian. The early to middle Pennsylvanian sea-level history inferred from the carbonate-dominated Bird Spring platform corresponds well with a recently published Pennsylvanian onlap–offlap history defined from the cyclothemic succession of the Donets Basin and with independent near-field reconstructions of glaciation during the Pennsylvanian. [Copyright &y& Elsevier]

Abstract: Two shell fragments, one of an undetermined cephalopod and one of an orthoconic nautiloid (Pseudorthoceratidae gen. et. sp. indet.), from the Pennsylvanian Buckhorn Asphalt Lagerstätte (Oklahoma) were studied to reconstruct paleotemperatures and to explore possible diagenetic alterations. For the first time, not only parts of the shell of an orthoconic nautiloid, but also its cameral deposits were sampled in high resolution. The mineralogy, geochemistry, and microstructure of both shell remains, the pseudorthoceratid and the undetermined cephalopod, were investigated in detail before high-resolution transects for oxygen and stable carbon isotopes were sampled. The shell fragment of the undetermined cephalopod showed no or very little diagenetic alteration. Therefore, the measured δ18O-variation (δ18O-range of 0.68‰) and the inferred temperature range of 28 to 31°C are interpreted to represent an original signal. The temperatures indicate that the specimen lived in shallow, warm tropical waters. The δ13C-signal, with a δ13C-range of 3.43‰ is interpreted to be the consequence of a strong metabolic effect. A septum of the phragmocone of the pseudorthoceratid nautiloid was only slightly altered by diagenesis and a largely original δ18O-signal could be obtained. The δ18O-values exhibit an inferred temperature range of 14 to 15°C indicating that this species lived in deeper and cooler waters. The cameral deposits were investigated in detail by energy dispersive X-ray (EDX) and by XRD–GADDS (X-ray diffraction — general area detector diffraction system) analyses. Part of the cameral deposits in the orthoconic nautiloid turned out to originally consist of high-Mg calcite (HMC) instead of the estimated aragonite. Anyhow, the massive cameral deposits show signs of strong small scale alteration resulting in a distinct spreading of oxygen-values. The oxygen and carbon isotope plots show a linear trend for the oxygen-carbon-correlation. This is interpreted as the mixing of two end-members with the lightest end-members suggesting a meteoric diagenesis with a diagenetic fractionation of the aragonite to low-Mg calcite (LMC) respectively the HMC to LMC and dolomite. The calculated temperatures of the pseudorthoceratid specimen and the undetermined cephalopod indicate two different paleoenvironments. Additionally, the pseudorthoceratid nautiloid displays the narrow range of temperatures in the deeper parts of the sea and the undetermined cephalopod the more fluctuating temperatures in the shallow areas. It is also shown how important a detailed investigation of microstructures and mineralogy of samples with an according cautious interpretation of the achieved dataset is. The importance of an intensive examination of samples is pointed out, to avoid small scale alterations to be overlooked, since this would lead to a misinterpretation of the results. [Copyright &y& Elsevier]

Abstract: The Wynyard Formation of Tasmania, Australia, provides the youngest evidence of grounded ice during the Late Carboniferous–Early Permian in the Tasmania Basin of southeastern Gondwana during the late Paleozoic ice age. Within the Wynyard Formation, four facies associations are recognized: 1) massive diamictite, 2) stratified diamictite, 3) conglomerate and sandstone, and 4) deformed mudstone and fine sandstone. A detailed facies analysis was performed in order to interpret the depositional processes and environments. The massive diamictite facies association contains massive diamictite and sandstone and was deposited primarily by iceberg rain-out in a subaqueous morainal bank setting. The stratified diamictite facies association is composed of stratified diamictite, sandstone, and conglomerate, and was deposited by debris flows and iceberg rain-out, and deformed by glacial pushing. The conglomerate and sandstone facies association is made up of cross-stratified, channelized conglomerate and pebbly sandstone that were deposited by glacial outwash on grounding-line fans. The deformed mudstone and fine sandstone facies association is composed of pervasively deformed pebbly mudstone and fine-grained sandstone that exhibit volcano, flame, and dyke structures. This facies association was deposited by a combination of suspension settling, iceberg rain-out, and soft sediment deformation, in a quiet distal proglacial setting. The facies analysis supports the interpretation that the Wynyard Formation was deposited by a wet-based, tidewater glacier or glaciers. The depositing glacier(s) occupied a ~40km-wide trough in northwest Tasmania. Based on the distribution of the Wynyard Formation and the presence of glacial deposits in other eroded troughs in Tasmania, glaciation occurred in the region within broadly eroded valleys. The Wynyard Formation and overlying mudstone of the Inglis Formation provide a glacial–postglacial signature similar to those in South Africa, Antarctica, and eastern Australia during the latest Carboniferous–Early Permian, therefore the climate warmed in southern Gondwana following this glacial interval. The continued glaciation in eastern Australia was a result of regional topography and oceanographic processes. [Copyright &y& Elsevier]

Abstract: Small spherical structures commonly termed sporocarps are widespread elements in Carboniferous permineralized peat. While sporocarps today are generally interpreted as fungal, their precise systematic affinities largely remain unknown. A specimen of the sporocarp-type Traquairia from the Lower Coal Measures (Lower Pennsylvanian) of Great Britain demonstrates a heretofore unknown feature in the form of a preformed aperture from which emerges a fascicle of radially oriented structures that are constricted sub-distally; transverse septa are present in the constricted areas of some of the structures. The outgrowths are morphologically similar to conidiophores bearing terminal conidia of certain extant fungi in the order Entomophthorales, and thus might suggest affinities of Traquairia with the Zygomycota. Alternatively, the outgrowths might represent sporulating hyphae of a parasitic or saprotrophic blastocladalean fungus or a peronosporomycete that used Traquairia as a nutrient source. [Copyright &y& Elsevier]

Abstract: Localized igneous intrusions with varying types of intrusion patterns were found in the Pennsylvanian–Permian coals in north China. Five typical patterns, including dike cut-through (pattern-I), dike cut-in (pattern-II), floor intrusion by sill (pattern-III), roof intrusion by sill (pattern-IV) and dual intrusions of roof and floor by sills (pattern-V), were investigated at five different underground profiles. It was found that the influence of localized intrusions on rank, petrology and coal quality characteristics are mainly related to the emplacement temperature, the style of heat transfer (convection or conduction), the intrusion forms (dike or sill) and size, the distance from the contact and the thermal properties of the surrounding rocks at the contact of the intrusion. Among the five patterns, only pattern-V was found to have two distinct contact metamorphic aureoles within a distance of 1–2 times of the thickness of the intrusion, whereas patterns I through IV show wave-like profiles of vitrinite-reflectance, ash and volatile matter. This resulted from the typical characteristics of “multiphasic and superimposed thermal metamorphic evolution” of north China coals. Except for the heat conduction by intrusion contact, the hydrothermal convection and tectonic-heat played important roles in heat transfer away from dike/sill. Intrusion-induced coal changes including coal rank, organic/inorganic composition and pore properties work together to influence the adsorption capacity of coals. The effect of intrusion upon the adsorption capacity of altered coals is related to the values of their altered coal ranks. Adsorption capacity is elevated from the Langmuir volume (VL) of 7.6 (pre-intrusion) to 17.5m3/t (post-intrusion) for altered bituminous coals and semi-anthracites with VRr<2.1%. In contrast, the adsorption capacity is moderately reduced from background levels of about 27.2m3/t to about 19.3m3/t for altered semi-anthracites and anthracites with VRr of 2.1%–3.4%. Adsorption capacity is significantly reduced (<5m3/t) for altered anthracites and meta-anthracites with VRr of >3.4%, because of the accumulation of coal basic structure unit and distinctly decreasing pores. The relationships between altered coal rank and adsorption capacity are different for different coals, which is mainly due to changes of pore characteristics and coal structures resulting from three important coalification jumps during contact and/or other heat metamorphism. [Copyright &y& Elsevier]

Abstract: Irregular aggregates of monazite-(Ce) to monazite-(Nd), up to 150μm in diameter, have been found in graywackes from the Protivanov Formation, Drahany Upland, Czech Republic. Monazite aggregates enclose a variety of detrital and authigenic minerals. Textural evidences suggest that they are of authigenic origin and grew during very low-grade metamorphism at a maximum temperature ~200–300°C in relation to a deep burial. Rarely, they enclose relics of detrital monazite with a chemical composition typical for high-grade monazite. Intensive fluid-related REE-remobilization occurred in relation to this very low-grade metamorphism. Authigenic monazite appears to form only in Ca-poor rocks. In Ca-rich graywackes, which underwent the same low-temperature metamorphic overprint, authigenic synchysite-(Ce) or parisite-(Ce) are common instead. In the overlaying Rozstání and Myslejovice Formations (T~150–200°C), remobilization of REEs was low and authigenic monazite did not form even in the Ca-poor graywackes. Authigenic monazite shows low concentrations of Th, U, Ca, Y+HREE, and a low Eu anomaly. The central parts of the aggregates are enriched in Nd+MREE, whereas the outer parts are enriched in La and Ce. Zoning pattern suggests an evolution in fluid chemistry during diagenesis/very low-grade metamorphism or it relates to different solubility of the individual REE-phosphates. The major source of REEs in the pore fluids are probably detrital minerals mainly monazite. Other minor sources of REEs probably include Fe-oxide/hydroxide and/or clay minerals, which could have contributed to the Nd+MREE-rich cores in the authigenic monazite. [Copyright &y& Elsevier]

Abstract: We examined four dispersed, coalified ovules, Trigonocarpus grandis, of medullosalean seed-fern affinity from the Late Pennsylvanian age Sydney Coalfield, Canada, which represent the larger type of the 7–8cm trigonocarpalean form species. At first glance it appears that the ovules are preserved like the usual Carboniferous foliar compressions, i.e. one coalified layer with one preserved anatomical tissue, the cuticle. However, careful sample preparation uncovered at least three coalified layers, and Schulze’s oxidative maceration process, which dissolves the coalified material, revealed several tissue layers. Altogether, eight sample forms were defined: (i) coalified layer, (ii) cuticle A, (iii) cupric+vitrain, (iv) vitrain, (v) cupric, (vi) cuticle B, (vii) alkaline solution and (viii) added coal seam material. The purpose of the study was twofold: first, to systematically analyze the forms by way of Fourier transform infrared (FTIR) spectrometry to fill a gap in chemical information that exits for coalified trigonocarpalean ovules of Carboniferous seed ferns; second, to use principal component analysis to focus on groupings as a function of chemical structure (functional groups) and to assess the different fossil forms in terms of FTIR chemical parameters, based on a 8×49 data matrix. Results include distinction among the three coaly sample forms, coalified layer (i), cupric+vitrain (iii) and cupric (v), based mainly, but not exclusively, on differences in carbonyl content, as well as length and branching of the polymethylenic chains. Important to note is the high aliphatic content of the cuticles as a signature of the biomacromolecules cutan/cutin. In particular, new insights into the structure of the original ovule are presented, and differences in chemistry are mainly a result of the complex structure of the precursor plant organ. [Copyright &y& Elsevier]

Peat mires retain a sensitive record of water-table (base-level) fluctuations throughout their accumulation. On this basis, coals provide one of the best opportunities to interpret high-resolution base-level change in ancient non-marine deposits. The petrographic composition of 275 samples collected from 11 localities along a 100 km south-west to north-east transect across the regionally extensive (>37 000 km2) Pennsylvanian (Upper Carboniferous) Fire Clay coal of the Central Appalachian Basin, USA was analysed to determine its internal stratigraphy. The coal is positioned within the late lowstand/early transgressive systems tract of a fourth-order depositional sequence. The results of the petrographic analyses reveal a cyclicity in the composition of the Fire Clay coal, which defines six units that are correlated over more than 100 km. Each coal cycle is characterized by a gradual upward transition from vitrinite-dominated to inertinite-dominated coal, which represents a 'drying-up' succession. Increased concentrations of resistant peat components at the top of the drying-up successions indicate reduced peat accumulation rates associated with slowing rate of water-table rise, and may represent a residue of peat remaining from a phase of exposure and erosion resulting from a falling water table. These drying-up successions are bound by surfaces that display an abrupt coal facies shift from inertinite-rich to vitrinite-rich coal, representing a rapid water-table rise. Each cycle represents markedly different mire conditions with different aerial distributions, which supports the notion of temporal disconnection between each unit of coal, and suggests that considerable time may be 'locked-up' in unit bounding exposure surfaces. Recognition that the rate of peat accumulation in a mire may vary considerably through time, has important implications for studies which assume that peat and coal successions provide continuous and time-invariant records of base-level fluctuations or palaeoecological change. [ABSTRACT FROM AUTHOR]

Abstract: Well-preserved megaspores are described for the first time from Pennsylvanian to Late Permian strata of the Baode region in Shanxi province, North China. A total of 20 species in 13 genera are described, amongst which one species Biharisporites grosstriletus sp. nov. is new. The other 19 are previously known from the Euramerican and Gondwanan floral provinces, but are described here for first time from the Cathaysian Province. Using first appearances of selected megaspore species and changes in species abundance in the succession, four assemblage zones can be recognised. In ascending order these are the Auritolagenicula renaulti-Setosisporites brevispinosus (RB, Moscovian), the Bentzisiporites margaritatus-Spencerisporites striatus (MS, Kasimovian-Roadian), the Biharisporites grosstriletus (G, Wordian-Capitanian) and the Biharisporites cf. foskettensis (F, Wuchiapingian) assemblage zones. Comparison with already known in situ megaspores indicates that the parent plants of the dispersed megaspores were mainly lycopods and this in turn indicates their likely palaeoenvironmental significance. Selaginella-like herbs and subarborescent lycopods which were low in abundance compared with arborescent lycopods in the early Pennsylvanian appeared to have become prevalent from the Late Pennsylvanian in northern China. However, some arborescent lycopods (mainly sigillarians) still played an important role in the Permian coal forming plants of the region. Several Carboniferous megaspores characteristic of Euramerica persist into the Mid Permian in North China, indicating that a warm and humid climate prevailed in this area during Pennsylvanian to Roadian, whereas the climate of Euramerica had already become arid by the end of the Carboniferous. This warm and humid climate in northern China made it a refuge for some typically Euramerican Carboniferous plants. From Roadian, with the disappearance of coal and marine sediments together with the appearance of red beds, the MS megaspore zone progressively changed to the G zone. This probably reflects the adaptation of the parent plants to a more and more arid climate. [Copyright &y& Elsevier]

Abstract: Mapping geological details and interpreting three-dimensional geometries in a highly heterogeneous outcrop such as the exposure at Big Rock Quarry has been a continuous challenge especially because high vertical cliffs make access to most of the rocks difficult for direct geological observations. Previous interpretations of facies architecture were derived from gamma–ray profiles, a core and measurements made on two-dimensional photomosaics. This paper represents the first attempt of three-dimensional interpretation of the geometry and facies pattern of the Jackfork nested channel complex deposited at the base-of-slope. Examination of the photo real model of the outcrop with assigned lithologies allowed extraction of accurate 3-D qualitative, as well as quantitative (channel dimensions) geometric information. This facilitated interpretation and reconstruction of the submarine channel complex architecture making possible correlations of strata exposed on the two sides of the quarry. Most of the exposed vertically and laterally stacked channels are large, aggradational with well-defined axial regions overlain by matrix-supported breccia which grades upward into amalgamated sandstones. The thickness of the sandstone decreases toward the southeastern end of the quarry where more shale is present. The channel infill consists of thin-bedded sandstones interlayered with shale which overlain the breccia. The upper part of the quarry is made up of smaller, lateral migrating channels. Significant channel width and thickness variation can be recognized at outcrop scale. Thirty-eight identified channels are characterized by a relatively low aspect ratio (4:1 to 32:1) with channel dimensions ranging from 25 m to 314 m wide and 2 m–24 m deep. Bed thickness distributions of various facies show that the sandstone comprises a significant proportion (83%) of the total channel thickness, while shale and breccia represent about 8%, and 17% respectively. This yields a high net-to gross ratio of more than 80%. Compared to previous reconstructions our 3-D photo real model is more accurate and it can be used to calibrate simulation of processes in deep-water environments. [Copyright &y& Elsevier]

A new Mazon-Creek-type fossil specimen is described as Sumixam maximus gen. and sp. nov., assigned to the taxon Archaeorthoptera Béthoux and Nel, 2002 (composed of Orthoptera and some fossil relatives): it exhibits one of the diagnostic character states of this taxon, which is the fusion of CuA (emerging from M + CuA) with CuP, or a branch of it. A more precise taxonomic assignment is out of reach. The new taxon exhibits a fusion of the anterior branch of MA with RP, and a point of divergence of MA and MP located near the point of divergence of CuA (from M + CuA), but lack a branching of CuPa. This unique combination of character states is probably derived with respect to a number of contemporaneous species. Sumixam maximus gen. and sp. nov. is most likely the closest known relative of the panorthopterans, which include all the recent Archaeorthoptera. [ABSTRACT FROM AUTHOR]

Abstract: The Pennsylvanian and Early Permian were times of extreme sea-level changes of >100 to perhaps up to 200m. For example, glacio-eustatic sea-level changes are well documented from the US Midcontinent, Moscow Basin and Yangtze Platform, where more than 100 stacked subtidal to supratidal sequences have been described. In contrast, carbonates developed in the Ural Mountains and South Guizhou of the Yangtze Platform were deposited in ramp and slope settings. δ13C values of whole rock samples from the US Midcontinent and Moscow Basin were intensively affected by diagenesis. Only well-preserved brachiopod shells maintained their original carbon isotope ratios. In contrast, limestones deposited in the deeper water slope environments were not affected by meteoric diagenesis and are interpreted to have mainly retained their carbon isotope ratios. Mean δ13C values of slope carbonates of the Yangtze Platform increase from about 3‰ during the Viséan and Serpukhovian to 5‰ at the Carboniferous–Permian boundary and decrease to values around 2‰ in the early Kungurian. This positive δ13C excursion coincides with low δ13C values in the Yangtze Platform successions, which were reset by meteoric diagenesis. The highest δ13C values recorded in the slope succession coincide with the inferred maximum glaciation that caused pronounced sea-level lowstands. Short-lived, but significant negative δ13C excursions in the Chinese slope succession are interpreted to reflect changes in ocean circulation due to sea-level rises which caused enhanced production and/or preservation of organic matter which influenced the subsequent early diagenetic cementation. [Copyright &y& Elsevier]

Abstract: During the Permian, peatland, as represented in extensive coal deposits, was a major component of the global carbon cycle. Carbon storage in peatland is a balance between decay and net primary production (NPP), which in turn are sensitive to variations in the concentration of atmospheric CO2 and O2. To evaluate peatland carbon storage and NPP during the Lopingian, a period thought to be characterised by higher atmospheric O2 and CO2 than modern levels, spectral analyses of geophysical data from a 15.1m thick Lopingian (Upper Permian) coal in southwestern China were conducted to define the time frame of temporal carbon accumulation in tropical peatland. The result shows that the mineral matter content (ash yield) of the coal was possibly influenced by 123ka (eccentricity), 35.6ka (obliquity) and 21.2ka (precession) Milankovitch periodicities. Using this timeframe and an understanding of carbon loss during coalification, the Lopingian tropical peatland carbon accumulation rate is calculated to be 61.1–73.0gC/m2/yr which is expected to correspond to a NPP of 611–1460gC/m2/yr respectively. A comparison between the predicted Pennsylvanian (Late Carboniferous) NPP and modern values indicates that the Permian NPP calculated is consistent with geochemical and paleobotanical models, supporting a proposal that productivity was mainly controlled by temporal atmospheric O2 and CO2 levels. [Copyright &y& Elsevier]

Late Carboniferous red-beds, < 700 m thick, at outcrop and in the subsurface of the Canonbie Coalfield can be assigned to the Warwickshire Group. They are preserved within the axial part of the Solway Syncline and are divisible into the Eskbank Wood, Canonbie Bridge Sandstone and Becklees Sandstone formations. Sedimentation largely took place on a well-drained alluvial plain, characterized mainly by early, primary oxidation of the strata. Large, northerly-flowing braided river systems were common, with overbank and floodplain fines deposited lateral to the channels; soils formed during intervals of low sediment aggradation. The Canonbie succession includes some of the youngest Carboniferous rocks preserved in the UK. Correlation of the Eskbank Wood Formation is equivocal, but using petrographical, heavy mineral, zircon age dating and palaeocurrent data, the Canonbie Bridge Sandstone Formation can be unambiguously correlated with the Halesowen Formation ofWarwickshire, the Pennant Sandstone Formation of SouthWales and the offshore Boulton Formation. This suggests that southerly-derived detritus travelled considerable distances from the Variscan highlands of Brittany and/or central Germany across the southern North Sea and UK areas, to a position some hundreds of kilometres north of that previously recognized. The Becklees Sandstone Formation has much in common with the Salop Formation of the English Midlands. It appears to have no preserved equivalent elsewhere in the UK or in the UK sector of the southern North Sea but resembles stratigraphically higher parts of the southern North Sea succession seen in the Dutch sector. [ABSTRACT FROM AUTHOR]

Abstract: Ten different types of microproblematic structures occur on the surfaces, and in epidermal and hypodermal cells of fern pinnules preserved in the Late Pennsylvanian Grand-Croix cherts from France. These include thick-walled spheres, some with a prominent exit site, aggregations of variously sized spheres that may be surrounded by a membrane or sheath, a cylindrical structure composed of polygonal compartments, and branched hyphae/filaments with intercalary swellings protruding from a small opening in the surface (probably a stomatal pore). Some of the structures likely were produced by some fungal group, and may represent (resting) spores, microsclerotia, and conidiophores. The affinities of the others, and sometimes even their biological nature, remain difficult to determine. Nevertheless, documenting these structures is important because it provides the first indication for vascular plant leaves that were colonized by different types of organisms in a late Paleozoic ecosystem. [ABSTRACT FROM AUTHOR]

new syntonopterid, Anglolithoneura magnifica gen. et sp. n., is described from a siderite concretion (nodule) from the Late Carboniferous (Langsettian) of Lancashire County (UK). The new genus is diagnosed on hind wing venation and compared with other syntonopterid genera. The new species is the first syntonopterid formally described from the Late Carboniferous of Europe. The systematic positions of other potential Syntonopteroidea ( Miracopteron mirabile, Bojophlebia prokopi, and specimens described in 1985 by J. Kukalová-Peck from Obora in the Czech Republic) are reconsidered. Wing venation synapomorphies are proposed for the Syntonopteroidea (sensu novo), and for a potential clade ((Ephemeroptera+Syntonopteroidea)+Odonatoptera) separated from the Palaeodictyopterida. The close relations of the new species with Lithoneura lameerei Carpenter, 1938 from Mazon Creek (Illinois, USA) provide additional support for a Euramerican connection during the Late Carboniferous. [ABSTRACT FROM AUTHOR]

Abstract: Geologic mapping in the northern Sierra Los Ajos reveals new stratigraphic and structural data relevant to deciphering the Mesozoic–Cenozoic tectonic evolution of the range. The northern Sierra Los Ajos is cored by Proterozoic, Cambrian, Devonian, Mississippian, and Pennsylvanian strata, equivalent respectively to the Pinal Schist, Bolsa Quartzite and Abrigo Limestone, Martin Formation, Escabrosa Limestone, and Horquilla Limestone. The Proterozoic–Paleozoic sequence is mantled by Upper Cretaceous rocks partly equivalent to the Fort Crittenden and Salero Formations in Arizona, and the Cabullona Group in Sonora, Mexico. Absence of the Upper Jurassic–Lower Cretaceous Bisbee Group below the Upper Cretaceous rocks and above the Proterozoic–Paleozoic rocks indicates that the Sierra Los Ajos was part of the Cananea high, a topographic highland during the Late Jurassic and Early Cretaceous. Deposition of Upper Cretaceous rocks directly on Paleozoic and Proterozoic rocks indicates that the Sierra Los Ajos area had subsided as part of the Laramide Cabullona basin during Late Cretaceous time. Basal beds of the Upper Cretaceous sequence are clast-supported conglomerate composed locally of basement (Paleozoic) clasts. The conglomerate represents erosion of Paleozoic basement in the Sierra Los Ajos area coincident with development of the Cabullona basin. The present-day Sierra Los Ajos reaches elevations of greater than 2600m, and was uplifted during Tertiary basin-and-range extension. Upper Cretaceous rocks are exposed at higher elevations in the northern Sierra Los Ajos and represent an uplifted part of the inverted Cabullona basin. Tertiary uplift of the Sierra Los Ajos was largely accommodated by vertical movement along the north-to-northwest-striking Sierra Los Ajos fault zone flanking the west side of the range. This fault zone structurally controls the configuration of the headwaters of the San Pedro River basin, an important bi-national water resource in the US-Mexico border region. [Copyright &y& Elsevier]

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Abstract: Three species groups, including two groups of corals and one of fusulinids, delineate the zone of favorable marine environments for these animals along the shelves bordering southwestern Laurentia during the Cisuralian (Early Permian). The three species groups are: the coral Protowentzelella group of late Asselian to early Sakmarian age, the fusulinid Eoparafusulina linearis group of late Sakmarian age, and the coral Pararachnastraea illipahensis group of late Artinskian to Kungurian age. Occurrences of these three species groups clearly outline most of the major paleotectonic features that were present along the southwestern margin of the Laurentian shelf at that time. The paucity of data in Mexico, however, leaves open the question of large-scale displacement on the Mojave–Sonora megashear, a feature proposed to cut across northern Mexico and southwestern USA, although the data presented here could be construed to suggest lack of significant displacement in post-Pennsylvanian time. [Copyright &y& Elsevier]

We describe a Pennsylvanian (Late Carboniferous) Parapostibulla edrioasteroid that competed for living space with an encrusting cryptostome bryozoan on the brachiopod Composita. The colonial bryozoan grew faster than the solitary edrioasteroid, and the bryozoan increased its colony size by slowly encircling the edrioasteroid. Neither organism was able to overgrow the other, even where the margins became thick, and each had to accommodate the presence and possible defenses of the other. Evidence for defensive measures by edrioasteroids has not previously been reported, but this interaction does emphasize that edrioasteroids could not move away from severe crowding or overgrowth by other organisms. [ABSTRACT FROM AUTHOR]

Abstract: Two specimens of compression strobili from the Bolsovian of the Kladno–Rakovník Basin, Czech Republic, were studied for in situ spores. Sporangia of strobili are disintegrated. Only fragments of sphenophyllalean axes and sphenophyllalean leaves occur in the rock together with the sporangia and sporangiophores. The direct evidence about sphenophyllalean affinity of strobili is that sporangia are connected with axis by a short non-scutelliform sporangiophore that is typical only for the genus Bowmanites Binney. The lack of morphological features of strobili does not enable the erection of a new species and, therefore, it is possible to classify the specimens only as Bowmanites sp. Reticulate spores comparable with the dispersed species Reticulatisporites muricatus Kosanke are reported for the first time as in situ from compression cone specimens and represent new morphological type of sphenophyllalean spores. [Copyright &y& Elsevier]

Abstract: We combine cyclo- and sequence stratigraphy along with whole rock δ 13C and conodont apatite δ 18O analysis to document high-frequency (104–105 yr) and My-scale sea-level changes for the Middle Pennsylvanian (Desmoinesian or Moscovian) Gray Mesa Formation of central New Mexico. Approximately 75 subtidal cycles (1–8m) are grouped into 4 1/2My-scale depositional sequences (40–80m). About 50% of the cycles show evidence of prolonged subaerial exposure at cycle tops with the development of calcretes, diagenetic mottling, and regolith intraclasts. High-resolution δ 13C analysis of whole rock limestones across nine of the cycles indicates that the cycle tops were diagenetically altered by isotopically light, meteoric fluids during sea-level fall and lowstand. These δ 13C trends support the interpretation that high-frequency sea-level changes were responsible for cycle development. Conodont apatite δ 18O values from sampled cycles indicate that the high-frequency sea-level changes were driven by glacio-eustasy combined with changes in surface seawater temperature (SST). δ 18O values from conodont apatite, spanning parts of three depositional sequences indicate that My-scale glacio-eustasy and/or SST changes controlled sequence development. δ 18O shifts indicate that the magnitudes of 104–105 yr glacio-eustasy were between ∼55 and 170+ m combined with tropical SST changes of ∼1.5°–6°C. Calculated My-scale glacio-eustatic oscillations were between ∼60 and 140m with SST changes of <3.5°C. The most plausible driver for the My-scale paleoclimate changes is long-period obliquity (∼1.2My) variations. These calculated high-frequency, glacio-eustatic values are similar or greater than Pleistocene values, and lie within the range estimated for other Middle Pennsylvanian successions using a variety of independent eustatic proxies. The similarity in range of magnitudes between high-frequency and My-scale sea-level changes combined with the large differences in magnitudes between individual high-frequency sea-level oscillations helps explain the lack of systematic cycle-stacking patterns within these Pennsylvanian icehouse sequences. [Copyright &y& Elsevier]

Abstract: A new fossil water mold (Peronosporomycetes), Galtierella biscalithecae nov. gen. et sp., consisting of coenocytic hyphae occurs as an intracellular endophyte in a partially degraded specimen of the reproductive organ Biscalitheca cf. musata (Zygopteridales) from the Upper Pennsylvanian Grand-Croix cherts (Saint-Étienne Basin, France). Some hyphal tips produce small spheres that subsequently develop into ornamented, opaque-walled oogonia; amphigynous antheridia encircle the necks of several immature oogonia. Also present are ovoid structures, which may represent differently shaped oogonia, hyphal swellings, or zoosporangia. Small dome-shaped structures, probably zoospore cysts, are attached to numerous host cell walls. This discovery sheds new light on the morphology and biology of water molds in a Carboniferous ecosystem. [Copyright &y& Elsevier]

Abstract: Modern low-oxygen marine systems exhibit patterns of molybdenum–uranium covariation that can be linked to specific attributes and processes of the depositional system, including (1) variation in benthic redox conditions, (2) the operation of particulate shuttles within the water column, and (3) the evolution of watermass chemistry. The importance of these factors in each depositional system can be assessed both from the degree of enrichment of authigenic molybdenum (Moauth) and uranium (Uauth) and from the (Mo/U)auth ratio of the sediment relative to the seawater Mo/U molar ratio of ∼7.5–7.9. In open-ocean systems with suboxic bottomwaters, Uauth enrichment tends to exceed that of Moauth owing to onset of Uauth accumulation at the Fe(II)–Fe(III) redox boundary, resulting in sediment (Mo/U)auth ratios less than that of seawater. As bottomwaters become increasingly reducing and at least occasionally sulfidic, the rate of accumulation of Moauth increases relative to that of Uauth, and sediment (Mo/U)auth ratios equal or exceed that of seawater. In restricted marine systems with permanently sulfidic deepwaters, the relative enrichment of Moauth and Uauth depends on additional factors. In the Cariaco Basin, which has an aqueous Mo/U ratio similar to that of seawater, the operation of a particulate Mn–Fe-oxyhydroxide shuttle serves to accelerate the transfer of Mo to the seafloor, leading to strong enrichments in Moauth relative to Uauth. In the Black Sea, the chemistry of the deep watermass has evolved to the point where its aqueous Mo/U ratio is only ∼0.04 that of seawater, as a consequence of which sediments deposited under deepwater influence are depleted in Moauth relative to Uauth. These Mo–U covariation patterns can be used to gain a better understanding of the watermass attributes and processes of ancient low-oxygen marine systems. Analysis of anoxic facies from two North American paleomarine systems, the Late Pennsylvanian Midcontinent Sea (LPMS) and the Late Devonian Seaway (LDS), reveals authigenic Mo–U relationships similar to those of the modern marine environments above, implying similar redox and hydrographic controls. The observed patterns are consistent with laterally unconfined circulation and strong watermass exchange within the LPMS, and with markedly restricted deepwater circulation in silled basins of the LDS. Patterns of authigenic Mo–U covariation may prove useful in analysis of other paleoceanographic systems to reveal aspects of watermass composition and environmental dynamics. [Copyright &y& Elsevier]

Abstract: Palynological analysis of ten core samples obtained from 867–729 m depth in the Pando X-1 Borehole (11° 36′07″ S, 67° 56′45″ W), northern Bolivia, is presented. Palynomorphs are fairly well-preserved although many contain abundant pyrite. The whole assemblage is composed of 48 species of which six are spores. Among the pollen grains, 21 are monosaccate and 19 bisaccate (11 striate species). Scarce scolecodonts, microforaminifera and algae are also present. Two assemblages are recognized on the basis of the stratigraphic distribution of species, mainly of the striate pollen grains. The lower assemblage (A1) is dominated by amorphous organic matter and scarce monosaccate pollen grains, trilete spores and microforaminifera. The upper assemblage (A2) is dominated by tracheids and brown and black phytoclasts and characterized by more diverse palynomorphs, mainly striate and non-striate pollen grains. The geographical and stratigraphic distribution of taxa reveals that many species are recorded from Pennsylvanian and Permian palynofloras elsewhere in Gondwana and Euramerica. The presence of Lahirites segmentatus, Limitisporites scitulus, Lunatisporites onerosus and Vittatina species, common with Brazilian palynofloras, supports a Moscovian age for the assemblage 2. This age is also supported by calcareous microfossils previously found in the same interval of this borehole. Twenty two species are first records in the Pennsylvanian of Bolivia (e.g., Florinites eremus, Protohaploxypinus varius, Striatopodocarpites antiquus, S. gondwanensis, S. solitus, Vittatina sp.). Palynofacies features of both assemblages are indicative of a shallow marine palaeoenvironment. Qualitative changes on the floral composition between A1 and A2 may reflect broadly local palaeoclimatical changes. The dominance of Cordaitales and Coniferales in A1 indicates a relatively more humid local condition than during A2 time, which is characterized by the appearance of abundant and diverse striate pollen grains related to new groups of Pteridosperms. These features are in agreement with a lower humidity or seasonally arid conditions prevailing in the terrestrial landscape near to the Copacabana marine palaeoenvironment. [Copyright &y& Elsevier]

Abstract: This paper provides a whole plant concept for a new species, Emporia cryptica sp. nov. Hernandez-Castillo, Stockey, Rothwell & Mapes (Emporiaceae: Voltziales), the fourth conifer to be reconstructed from the rich fossil biota at the Late Pennsylvanian, Hamilton Quarry, Kansas. E. cryptica has an orthotropic stem, lateral plagiotropic branches with simple leaves, simple pollen cones, and compound ovulate cones. Branches have an endarch eustele with dense wood surrounding a parenchymatous pith with sclerotic nests/plates, and secondary xylem tracheids with multiseriate hexagonal bordered pits. Leaves on both penultimate and ultimate branches are simple and amphistomatic with two adaxial stomatal bands, monocyclic and dicyclic stomata, and two narrow abaxial rows of stomata with numerous trichome bases. Pollen cones are simple with helically arranged microsporophylls and adaxial pollen sacs. Prepollen is monolete, eusaccate, and monosaccate (Potonieisporites Bharadwaj). Ovulate cones are compound with bilaterally symmetrical dwarf shoots in the axils of helically arranged forked bracts. Axillary dwarf shoots bear numerous sterile scales interspersed with two megasporophylls, each bearing a single inverted terminal ovule. This plant displays morphological and cuticular characters similar to several morphogenera of Paleozoic walchian conifers but is most comparable to the fossil plant species Emporia lockardii and Hanskerpia hamiltonensis. E. cryptica is the only walchian conifer where ovules and seeds with megagametophytes, immature embryos and mature embryos have been documented, demonstrating that the most ancient conifers possessed seed dormancy and polycotyledonary embryos. This reproductive biology is similar to that of many Mesozoic and extant conifers with saccate pollen except for the presence of prepollen grains that are common among Paleozoic walchian conifers. [Copyright &y& Elsevier]

Abstract: In the Stephanian B in eastern equatorial Pangaea, a large freshwater lake was formed in the continental basins of the west, central and northeast Bohemia, Czech Republic with a total area estimated at 5000–10,000 km2 and a lifetime of 50 to 500 ky. Its size exceeded that of any Permian–Carboniferous lake in the European basins of that period so far described. Continual sedimentation of organic-rich, seasonally laminated clayey–silty lake deposits produced a unique high-resolution record of part of the Stephanian B climate in the studied region. An extraordinarily large trophic web of fish assemblages also proves the temporal stability of this meromictic oligotrophic lake. The lake hydrology was inferred from the chemical and isotopic analyses of the autochthonous carbonates, particularly siderite, and analysis of organic matter. The environmental and weathering conditions in the lake watershed were inferred from analysis of palynospectra and detrital clay minerals. The lake passed through several stages of development including an initial highstand with peak productivity, a stepwise increase in mineralization accompanying gradual lake regression, a lowstand in the middle part of its lifetime, a partial lake recovery, and then a final transition to a shallow lacustrine-deltaic system. Lake regression was triggered by a long-term decrease in the P/E ratio coupled with increasing seasonality and accompanied by a decrease in intensity of chemical weathering in the drainage basin. Considerable vegetation response to fluctuating lake levels suggests complex environmental changes. During the initial lake highstand, abundant and diversified assemblages of xerophilous elements prevailed, spores of ferns prevailed during the regressive episode, and spores of lycopsids abruptly increased at the lowstand and remained dominant in the palynospectra of the second lake highstand. Final transition to a lacustrine-deltaic system was associated with pronounced increase in sphenopsids and ferns. These changes can be attributed to Milankovitch-like climate change from warm–wet to warm–seasonal dry, and may be inferred to have been responsible for Stephanian continental cyclothems. The entire Stephanian B period was more humid than the preceding Barruelian and subsequent Stephanian C in the Czech basins, thus revealing a climate cycle at a timescale of several million years, which is discussed in relation to southern Gondwana ice sheet stability. [Copyright &y& Elsevier]

Abstract: The Middlesboro Basin, southeastern Kentucky, occurs on the Cumberland Overthrust Sheet and includes a ca. 5.5-km diameter impact structure. The Lower and Middle Pennsylvanian coal-bearing strata are faulted, with some evidence for shock metamorphism. The event post-dated the latest-Pennsylvanian–early-Permian thrusting and was likely prior to late-Mesozoic entrenchment of drainages. The impact of a 0.5-km meteor traveling at ca. 60,000 km/h would release about 1 EJ, the approximate equivalent of the instantaneous combustion of 30 Mt of coal. The coal rank, while increased slightly above the regional level, still is within the upper portion of the high volatile A bituminous rank range. This helps to constrain the depth of burial at the time of the impact. The coal would have had to have been at a depth of a few kilometers to have avoided a more substantial rank increase. In addition, it is possible that some of the coal rank increase might be attributable to movements along the cross-cutting Rocky Face fault, unrelated to the impact. [Copyright &y& Elsevier]

Abstract: If time and heating rate are important agents in coal maturation, one might expect to see differences in chemical changes in response to maturation depending on the means of increased rank. Using a suite of samples obtained from an intruded Pennsylvanian-age coal in southern Illinois, we present whole-coal chemical data. Comparing these data to extant geochemical data for coals that have undergone normal burial maturation, we evaluated the hypothesis that if coal alteration occurs rapidly (due to intrusion) rather than gradually (burial maturation), then different relationships are seen in chemical composition (proximate and ultimate analyses) and vitrinite reflectance. The Pennsylvanian-age (Asturian [Westphalian D]) Springfield (No. 5) coal is mined at the Big Ridge Mine, near Eldorado, southern Illinois. This high volatile B bituminous coal was intruded by an ultramafic igneous intrusion during the early Permian. Alteration occurs out to ~1.2× dike thickness and includes an increase in random vitrinite reflectance (R m) from levels ~0.7% to over 5.3%, loss of liptinites, and formation of devolatilization vacuoles and fine mosaic texture. Decreases in volatile matter (VM) and increases in fixed carbon (FC) appear to be less than would be expected for the level of reflectance seen within the alteration halo. Carbonate minerals have a major influence on proximate analyses but even following the removal of carbonates, the decrease in VM is still less than would be seen in coals of similar vitrinite reflectance that were altered by normal burial maturation. Carbonate mineralization also contributes to variability in ultimate analysis values approaching the intrusion, particularly for %C and %O. After carbonate removal, data for these coals do not appear to follow the normal burial coalification tracks when plotted on a van Krevelen diagram and on a Seyler chart. These differences suggest that a slightly different maturation pathway may have been followed by these coals and by others that were altered rapidly by intrusion. [Copyright &y& Elsevier]

Abstract: Cuticles have been macerated from suitably preserved compressed fossil foliage by Schulze''s process for the past 150years, whereas the physical–biochemical relationship between the “coalified layer” with preserved cuticle as a unit has hardly been investigated, although they provide complementary information. This relationship is conceptualized by an analogue model of the anatomy of an extant leaf: “vitrinite (mesophyll)+cuticle (biomacropolymer)=compression”. Alkaline solutions from Schulze''s process as a proxy for the vitrinite, are studied by means of liquid–solid states Fourier transform infrared spectroscopy (FTIR). In addition, cuticle-free coalified layers and fossilized cuticles of seed ferns mainly from Canada, Spain and Argentina of Late Pennsylvanian–Late Triassic age are included in the study sample. Infrared data of cuticle and alkaline solutions differ which is primarily contingent on the mesophyll+biomacropolymer characteristics. The compression records two pathways of organic matter transformation. One is the vitrinized component that reflects the diagenetic–post-diagenetic coalification history parallel with the evolution of the associated coal seam. The other is the cuticle that reflects the sum-total of evolutionary pathway of the biomacropolymer, its monomeric, or polymeric fragmentation, though factors promoting preservation include entombing clay minerals and lower pH conditions. Caution is advised when interpreting liquid-state-based FTIR data, as some IR signals may have resulted from the interaction of Schulze''s process with the cuticular biochemistry. A biochemical-study course for taphonomy is suggested, as fossilized cuticles, cuticle-free coalified layers, and compressions are responses to shared physicogeochemical factors. [Copyright &y& Elsevier]

Abstract: Conventional (one-dimensional) chemostratigraphy of marine carbonates assesses the chemical archive of individual stratigraphic sections and their correlation in space and time. Whereas this approach has shown to be of value when linking isobathymetric domains, usually characterised by similar facies, more caution is needed when correlations are extended across different physiographic settings and hence different facies belts. Here, the spatial geochemical record of Pennsylvanian platform-margin-to-basin transects across a bathymetric range of about 800 m is documented and discussed in a process-oriented context. Particularly, the presence of layered palaeo-water masses and their potential control on slope facies distribution and geochemical properties requires attention. Whereas Carboniferous thermo- and/or chemo-clines most likely affected depth-related slope facies zonation, it was facies change and hence, variances in porosity–permeability properties, that controlled differential early burial diagenetic alteration. Specifically, the lower-slope related breccia facies is characterised by higher volumes of early burial carbonate cements. This implies that these sediments entered the shallow-burial domain with a considerable open pore space and gave way to an increased rock:fluid ratio. Whereas the δ 13C record is invariant with bathymetry, the more diagenesis-sensitive δ 18O proxy, records pronounced shifts observed across major facies boundaries. From this it is concluded that although the primary controlling factor of slope facies distribution with depth is probably palaeoceanographic in nature, it is differential rock:fluid ratios that control the first-order, spatial shifts in δ 18O composition. These findings show that one-dimensional chemostratigraphy will severely underestimate the complexity of three-dimensional (bathymetric) data sets across platform margins. This is of relevance for the interpretation of the geochemical archive of fossil carbonate platforms in general. [Copyright &y& Elsevier]

Abstract: High-diversity marine biotic communities characterize the lower Kasimovian (Upper Pennsylvanian) carbonates of the Las Llacerias Formation in the Ándara Massif (Picos de Europa Province, Cantabrian Mountains, Spain). The carbonates accumulated on a small thrust-top ramp system. Within the shallow, low-energy and euphotic realms, biotic communities were characterized by abundant photozoans (calcareous algae and cyanobacteria) and heterozoans including filter and suspension feeders (calcareous and siliceous sponges, bryozoans, brachiopods, crinoids), diverse other metazoans (rugose solitary and colonial corals, tabulate corals, bivalves, gastropods and echinoids), benthic foraminifers including very abundant small incrusting “tubiforms” and conspicuous swarms of cement-filled spheres (calcispheres or Penella). Small-sized buildups of chaetetid sponges, syringoporids, branching rugose corals, Anthracoporella and phylloid algae commonly developed in these shallow-water environments. Meanwhile, mud mounds formed at greater water depths, mostly below the lower limit of the phothic zone. The occurrence of such diverse biotic communities and the grain composition of the shallow-water deposits, not recorded in the platform-top successions of the antecedent Bashkirian–Moscovian carbonate shelf (Valdeteja and Picos de Europa formations) are interpreted as linked to increased nutrient levels (mesotrophic to mildly eutrophic conditions) in the actual sea-surface water. The nutrients are inferred to have resulted from land-derived fluxes from the rivers draining the adjacent growing Variscan Orogenic chain. Nutrients were subsequently transported into the narrowed marine shallowing foreland basin located in the eastern side of Pangea, within the palaeoequatorial humid belt. Comparison to the Pennsylvanian Auernig Group in the Carnic Alps allows the discrimination between the influence of land-derived versus upwelling-derived nutrients, providing a useful tool in the interpretation of biotic assemblages in the fossil rock record. [Copyright &y& Elsevier]

Abstract: Four megaspore genera: Cystosporites, Rotatisporites, Zonalessporites, and Valvisisporites were isolated from palaeokarst fill deposits of early Middle Pennsylvanian age, hosted within Ordovician limestones at Central Quarry in Central, Kendall County, Illinois, U.S.A. Five uncompacted megaspore species were identified and studied using scanning and transmission electron microscopy (SEM and TEM). The species Valvisisporites sculptus Bhardwaj is emended based on improved morphological and new ultrastructural data. The genus Pseudovalvisisporites Lachkar is recognized as a junior synonym of Valvisisporites. The ontogenetic development of aborted and functional Cystosporites diabolicus megaspores is investigated and the timing of sporopollenin deposition in both the exine and massa is reported. In Carboniferous megaspores, the importance of detailed investigation of the periapertural region is emphasized by the discovery of fusiform lamellate thickenings in Valvisisporites and Rotatisporites. The taxonomic and systematic importance of these features are considered in light of the otherwise highly conserved ultrastructure that is recognized in many lycopsid megaspores of this age. [Copyright &y& Elsevier]

Ten newly recovered Dunbarites specimens significantly extend the known stratigraphic range of Dunbarites. These include the first documented Midcontinent Basin records of the Missourian type species Dunbarites rectilateralis (Miller, 1930) from north-central Oklahoma. Additional species of Dunbarites from south-central Oklahoma and north-central and West Texas are described as Dunbarites wewokensis n. sp. and Dunbarites boardmani n. sp. Although Dunbarites is an extremely rare component (∼0.025 percent) of Middle and Upper Pennsylvanian ammonoid assemblages, Ruzhencev and Bogoslovskaya (1971, 1978) suggested that Dunbarites.and Parashumardites Ruzhencev, 1939 be used as genozone markers for the Kasimovian [Zhigulevian] Stage (Missourian in North America). As demonstrated by this report, the range of Dunbarites is not confined to the Kasimovian, thereby precluding its use as a Kasimovian Stage indicator. [ABSTRACT FROM AUTHOR]

New data on the Akkermanov deposit characterized by specific structure and composition of primary (carbonate) and secondary (manganese oxide) ores are presented. Distribution of mineralization in host rocks and weathering crusts is considered. It is shown that manganiferous carbonate rocks, which host orebodies, formed in a marine basin with well-aerated bottom waters. Oxide ores are mainly composed of crystalline pyrolusite produced by multiple processes of the oxidation of manganese compounds. In this respect, the Akkermanov deposit differs drastically from all manganese deposits developed in Russia and Ukraine. [ABSTRACT FROM AUTHOR]

Abstract: Late Stephanian and Early Permian floras were collected in eight localities of the Boskovice Basin. More than 2700 specimens were studied. The Carboniferous wet-type flora (Rosice–Oslavany Formation) is relatively hygrophilous with a dominance of ferns (Pecopteris cyathea and P. densifolia) and a smaller representation of sphenopsids (Annularia sphenophylloides). Pteridosperms and cordaitaleans are rare. Conifers (Ernestiodendron filiciforme), as drier-type elements, occur locally above the 1st (uppermost) coal seam of the Rosice–Oslavany coals together with many representatives of pteridosperms (medullosans, Odontopteris schlotheimii). This indicates the beginning of seasonality and aridisation of the climate. The Permian flora is dominated by conifers and is of an arid character. Some horizons contain a relatively high proportion of pteridosperms (Zbýšov, Říčany and Zboněk–Svitávka horizons), however, the species spectrum differs and the Permian pteridosperms are mainly represented by peltasperms (Autunia conferta). Ferns and sphenopsids are extremely rare in the Permian horizons. The flora reflects changes in the basin from relatively wet climate in the Rosice–Oslavany Formation to the seasonal and “dry” climate during the Permian. The Permian extrabasinal floral elements preserved in fossiliferous horizons grew in the basin during the seasonal climate. The red sediments outside the fossiliferous horizons are barren, presumably reflecting a semi-arid climate. The seasonality and “less” or “more” dry periods during the Permian are documented changes in diversity and dominance of the flora, and by cluster analysis. Using unconstrained Jaccard''s analysis, the Carboniferous “wet-type” flora is clearly separated from the “dry-type” Permian flora. Even though the Chudčice Horizon is approximately in the middle of the section, it is placed in this analysis at the top of the dendrogram together with the “dry-type” floral clusters. This analysis reflects an aridisation trend rather than biostratigraphically determined changes. As a result of our excavations, 15 species are here for the first time reported from the Boskovice Basin: Pecopteris cf. bredovii, Remia pinnatifida, Odontopteris lingulata, Neurocallipteris gallica, N. planchardii, Rhachiphyllum aff. curretiensis, ?R. subauriculata, Dicranophyllum longifolium, Culmitzschia angustifolia, Hermitia arnhardtii, H. germanica, H. rigidula, H. schlotheimii, and bifurcated leaves of uncertain affinity. [Copyright &y& Elsevier]

Abstract: About fifty compression specimens belonging to four species of Polysporia from the Kladno–Rakovník Basin of the central and western Bohemian Carboniferous continental basins and Intra-Sudetic Basin of the Czech Republic were studied macromorphologically and for in situ spores. Their stratigraphic range is from the Bolsovian to the Stephanian B. Polysporia rothwellii sp. nov., P. drabekii sp. nov. and P. radvanicensis sp. nov. are proposed as new species. Polysporia is reconstructed as a sub-arborescent plant with a principal axis with sterile and fertile apical portions. P. rothwellii and P. drabekii are preserved only as clusters of micro- and megasporophylls on specimens not in connection to an axis, and their identification and classification is based mainly on in situ spores. Micro- and megasporangia of some specimens of Polysporia occur together on axes, however, usually they are not arranged in a distinct pattern and only occasionally the distinct transition among micro- and megasporangia is to be seen. In situ megaspores are correlated with the dispersed species Valvisisporites auritus (Polysporia radvanicensis and P. drabekii), Expansisporites westphalensis (Polysporia rothwellii) and Triletisporites bohemicus (Polysporia robusta). In situ microspores are correlated with the dispersed species Endosporites zonalis (Polysporia robusta), E. globiformis (Polysporia rothwellii) and E. cf. formosus (Polysporia drabekii). Some of Kidston''s type material of Polysporia from UK was re-examined and yields megaspores of the Expansisporites valvatus-type and microspores of the Endosporites globiformis-type. A review of in situ and dispersed occurrences Valvisisporites, Pseudovalvisisporites, Triletisporites, Expansisporites megaspores and Endosporites miospores is given. [Copyright &y& Elsevier]

Abstract: A survey of the anatomically preserved flora of the Grand-Croix cherts (Late Pennsylvanian, Saint-Etienne basin, France) is presented following a study of collections preserved in the Swedish Natural History Museum, Stockholm in complement to previous investigations on the original material kept in France. An exhaustive list of the flora is provided, confirming the particular importance of this permineralized plant assemblage that is one of the most diverse for the Late Pennsylvanian. The observed occurrence of taxa and organs confirms a previous quantitative study based on material in the French collections: cordaiteans are both the most common taxa and the most important contributors to peat volume, whilst leaves are the most common and abundant organs. However, the seed ferns are the most diverse group of plants before cordaiteans and ferns; the exceptional diversity of medullosan ovules is of particular interest. The Grand-Croix flora is compared with that of the nearby Early Permian basin of Autun. The two assemblages have 21 genera, but only 6 species, in common, and this may be explained by differences in age and taphonomy. The Grand-Croix flora is also similar to that of American coal balls of the same age and, despite taxonomic differences, it is significant that several species of ferns and seed ferns are common to the vegetation of the French limnic and American paralic basins. [Copyright &y& Elsevier]

In this study we present the workflow and results of 2D frequency domain waveform tomography applied to the global-offset seismic data acquired in central Poland along a 50-km long profile during the GRUNDY 2003 experiment. The waveform tomography method allows full exploitation of the wide-aperture content of these data and produces in a semi-automatic way both the detailed P-wave velocity model and the structural image (i.e., perturbations in respect to the starting model). Thirteen frequencies ranging from 4 to 16 Hz were inverted sequentially, gradually introducing higher wavenumbers and more details into the velocity models. Although the data were characterised by relatively large shot spacings (1.5 km), we obtained clear images both of the Mesozoic and Permian sedimentary cover. Velocity patterns indicated facies changes within the Jurassic and Zechstein strata. A high velocity layer (ca. 5500 m/s) was found near the base of Triassic (Scythian), which made the imaging of a deeper layer difficult. Nevertheless, we were able to delineate the base of the Permian (i.e., base of the Rotliegend), which was not possible to derive from conventional common-depth-point processing, as well as some deeper events, attributed to the Carboniferous. The sub-Permian events formed a syn-form which favoured our previous interpretation of a depression filled with Upper Carboniferous molasse. The validity of the waveform tomography-derived model was confirmed by well-log data. Forward ray-tracing modelling and synthetic seismograms calculations provided another justification for the key structures present in the waveform tomography model. [ABSTRACT FROM AUTHOR]

Idiognathodus simulator (Ellison 1941) and Idiognathodus eudoraensis n. sp. constitute two members of a distinct group of Late Pennsylvanian species that are characterized by an eccentric groove on the PI element and Type IIIb symmetry, where dextral and sinistral P1 elements show different morphological features. The oldest species, Idiognathodus eudoraensis n. sp., probably developed from a species of Idiognathodus during the late middle Kasimovian. The simulator group is not closely related to Streptognathodus, which is characterized by a deep medial trough. The distinctive morphology of I. simulator [s.s.], redescribed here, in conjunction with its widespread distribution in North America and Eurasia, has led its first appearance to be selected as the event marker for the base of the global Gzhelian Stage. The simulator group includes other species that have been named in Eurasia, and will require additional work to adequately resolve species ranges and interpret its evolutionary history. [ABSTRACT FROM AUTHOR]

The long-standing difficulty of correlating Pennsylvanian strata among provincial faunal regions is resolved by effecting ‘digital’ correlation of major glacial-eustatic cyclothems that represent highstands when certain species achieved more global distribution than usual. In the late Moscovian-early Gzhelian (late Desmoinesian-early Virgilian) succession in the midcontinent United States, several major cyclothems are correlated, by both conodont species in common and cyclothem scale, with cyclothems in Russia (Moscow Basin) and Ukraine (Donets Basin), and the remaining cyclothems fit into the framework by position and scale. In this way the suggested event marker for the global Kasimovian-Gzhelian stage boundary (first appearance of Idiognathodus simulator) is supported, while possible event markers for the Moscovian-Kasimovian boundary await further evaluation. [ABSTRACT FROM AUTHOR]

The article talks about the upper Pennsylvanian (Missourian) Ammonoid Pennoceras from the North American Midcontinent. It also documents the first record in the Midcontinent of the type of species of Pennoceras, P. seamani Miller and Unklesbay, 1942, from the Hushpuckney Shale equivalent in southeastern Kansas.

Key aspects of the morphology, autecology, systematics and taphonomy of the crustacean syncarids from the Montceau Lagerstätte (Upper Carboniferous, Stephanian B; France) are presented. Palaeocaris secretanae is the most abundant faunal element of the Montceau biota and shows striking morphological similarities with Palaeocaris typus from the Mazon Creek Lagerstätte (Westphalian D; Illinois, USA). Palaeocaris secretanae was a shrimp-like animal with a short head (no head shield), large mandibles, 14 trunk segments (the first one being reduced) and a fan-like caudal termination. Both the body and the appendage design indicate abilities for crawling on the substratum (slender endopods) and for escape reaction (uropodal fan, pleonal flexibility), although swimming activities may have been reduced (trunk appendages with small flap-like exopods). Details of the appendages involved in feeding, e.g. mandibles and maxillipeds, indicate poor ability for predation but point to an omnivorous detritus feeding mode. Poorly developed respiratory organs (small cylindrical epipods) suggest a relatively low level of locomotory activity. The field of vision may have been large and panoramic (stalked eyes). Rows of pores on 12 trunk segments are interpreted as possible sensory organs used for current detection. Females were brooding eggs (clusters of eggs preserved along anteroventral trunk). Microprobe analysis indicates that siderite is the major component of the nodules. Four events played a key-role in the three-dimensional preservation of syncarids: (1) rapid burial, (2) minimal decomposition, (3) phosphatic mineralization shortly after the animal's death and (4) nodule formation around the carcass. Palaeocaris secretanae is morphologically close to Recent syncarids such Anaspides tasmaniae (freshwater streams, Australia) in its general body plan and detailed anatomy, e.g. mouth parts, indicating morphological stasis in syncarids over more than 200 million years. [ABSTRACT FROM AUTHOR]

Abstract: Using density-gradient centrifugation, within-sample heterogeneity in C/N, δ13C, and δ15N was determined for a sample of the Blue Gem coal bed (Middle Pennsylvanian, Duckmantian (Westphalian B), Breathitt Formation) and related to maceral (petrographically identifiable organic component) composition. Relatively pure macerals were separated by density, with purities up to 99% in the case of vitrinite in fractions around 1.3 g/mL. Lower density fractions (∼1.2 g/mL) contain predominantly liptinite (∼75%) but also significant amounts of vitrinite (∼20%). Denser fractions contain increasing amounts of inertinite, with several fractions between 1.37 and 1.44 g/mL containing >98% total inertinite. Within these denser fractions, semifusinite concentrated at lower densities than did fusinite. The separation of macerals by density allowed a more detailed evaluation of the isotopic composition of relatively pure macerals within a single coal. δ13C becomes increasingly heavy across the density gradient, with δ13C values being lightest in the liptinites, followed by vitrinite, and then semifusinite and fusinite; by contrast, δ15N becomes lighter across the same density range. C/H increases with density, reflecting a general decrease in aliphatic components and increase in aromatic components. C/N follows a similar pattern, ranging from <40 to over 100, increasing significantly at densities >1.32, the point at which inertinite macerals begin to predominate over vitrinite. The isotopic composition of macerals reflects chemical composition, which in turn reflects: 1) the original composition of plant tissues from which the macerals originated; 2) early diagenetic changes; and 3) changes during coalification. Macerals derived from lipid-rich precursor materials (liptinites) have more depleted δ13C values (∼2‰) relative to those derived from woody tissues (vitrinite). Fusinized material, derived from fossil charcoal, has δ13C values enriched by ∼0.5‰ compared with the vitrinite, consistent with the results from combustion experiments using modern plant tissues. Vitrinite fractions have enriched δ15N values relative to inertinite fractions, which may reflect early diagenetic changes in woody tissues involving preferential loss of 14N, possibly due to bacterial activity during the peat-forming stage. Due to the within-sample variability in carbon isotopic composition reported here, it is suggested that chemostratigraphic studies based on Type III kerogen (including both dispersed organic matter and coals) carefully consider the associated effects of variability in maceral composition. [Copyright &y& Elsevier]