Sydney Coalfield Research Articles

Combined DC resistivity and induced polarization (DC-IP) for mapping the internal composition of a mine waste rock pile in Nova Scotia, Canada

Mine waste rock piles (WRPs) can contain sulfidic minerals whose interaction with oxygen and water can generate acid mine drainage (AMD). Thus, WRPs can be a long-term source of environmental pollution. Since the generation of AMD and its release into the environment is dependent on the net volume and bulk composition of waste rock, effective characterization of WRPs is necessary for successful remedial design and monitoring. In this study, a combined DC resistivity and induced polarization (DC-IP) approach was employed to characterize an AMD-generating WRP in the Sydney Coalfield, Nova Scotia, Canada. Two-dimensional (2D) DC-IP imaging with 6 survey lines was performed to capture the full WRP landform. 2D DC results indicated a highly heterogeneous and moderately conductive waste rock underlain by a resistive bedrock containing numerous fractures. 2D IP (chargeability) results identified several highly-chargeable regions within the waste, with normalized chargeability delineating regions specific to waste mineralogy only. Three-dimensional (3D) DC-IP imaging, using 17 parallel lines on the plateau of the pile, was then used to focus on the composition of the waste rock. The full 3D inverted DC-IP distributions were used to identify coincident and continuous zones (isosurfaces) of low resistivity (<30 Ω-m) and high normalized chargeability (>0.4 mS/m) that were inferred as generated AMD (leachate) and stored AMD (sulfides), respectively. Integrated geological, hydrogeological and geochemical data increased confidence in the geoelectrical interpretations. Knowledge on the location of potentially more reactive waste material is extremely valuable for improved long-term AMD monitoring at the WRP.

Rodlets from Compressed Medullosalean Plant Fossils: Chemical and Morphological Studies (Late Pennsylvanian Sydney Coalfield, Canada)

Abstract Fragmented compression specimens of medullosalean fronds have been voluminously described over the past 200 years. However, the literature on rodlets is scarce. We addressed the questions (i) of common occurrence in these fronds, (ii) what made the fronds so strong to bear such a biomassive load, and (iii) what is the chemical make up of rodlets that expressed as striae and ridges (medullosalean hallmark) occur on these fronds? Recovered were soluble and insoluble, black, round and flat, opaque or translucent rodlets that are up to 5 mm long and ca. 10-111 μm wide, and are typed as (i) transparent, (ii) insoluble, or (iii) soluble in Schulze’s solution. In situ insoluble rodlets can be distinguished from associate coal and cuticle-free compression foliage and rachides by relatively high aromaticity and low aliphatics, although their chemical composition is unknown. Rodlets are presumably related to sclerenchymatous tissue in support of strength/stability of these sizeable medullosalean fronds.

Five-year performance monitoring of a high-density polyethylene (HDPE) cover system at a reclaimed mine waste rock pile in the Sydney Coalfield (Nova Scotia, Canada).

Cover systems are commonly placed over waste rock piles (WRPs) to limit atmospheric water and oxygen ingress and control the generation and release of acid mine drainage (AMD) to the receiving environment. Although covers containing geomembranes such as high-density polyethylene (HDPE) exhibit the attributes to be highly effective, there are few, if any, published studies monitoring their performance at full-scale WRPs. In 2011, a HDPE cover was installed over the Scotchtown Summit WRP in Nova Scotia, Canada, and extensive field performance monitoring was conducted over the next fiveyears. A range of parameters within the atmosphere, cover, waste rock, groundwater and surface water, were monitored and integrated into a comprehensive hydrogeochemical conceptual model to assess (i) atmospheric ingress to the waste rock, (ii) waste rock acidity and depletion and (iii) evolution of groundwater and surface water quality. Results demonstrate that the cover is effective and meeting site closure objectives. Depletion in oxygen influx resulted in slower sulphide oxidation and AMD generation, while a significant reduction in water influx (i.e. 512 to 50mm/year) resulted in diminished AMD release. Consistent improvements in groundwater quality (decrease in sulphate and metals; increase in pH) beneath and downgradient of the WRP were observed. Protection and/or significant improvement in surface water quality was evident in all surrounding watercourses due to the improved groundwater plume and elimination of contaminated runoff over previously exposed waste rock. A variably saturated flow and contaminant transport model is currently being developed to predict long-term cover system performance.

Linking Dolerotheca-like prepollen organs with Alethopteris pseudograndinioides foliage and assessing chemical properties of in situ prepollen grains: Implications for reconstructing Pennsylvanian-age alethopterid seed ferns

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 1H magnetic resonance, high precision liquid and pyrolytic-gas chromatography, and mass/charge ratios.The organs were tripartite, campanulate (bell-shaped) with lobate margins ca. 20mm in diameter and ca. 30mm long, and contained hundreds of elongate sporangia that were up to 8mm long and filled with huge up to 833μm 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.

Secretory organs: Implications for lipoid taxonomy and kerogen formation (seed ferns, Pennsylvanian, Canada)

Secretory organs likely evolved with land plants in Silurian-Devonian time, but it is questionable if they were passed on to living cycadaleans upon the extinction of seed ferns (Triassic-Jurassic?). They are defined as ducts of schizo-, lysig- or rhexigenous origin that exuded a heterogeneous lipoid mixture that fossilized as secretory products (droplets). In this study we detailed (1) the physical properties and distributions based on the compression-preserved Neuropteris ovata var. simonii and Laveineopteris rarinervis frond sections (Late Pennsylvanian Sydney Coalfield, Canada). Examined were also 1300 cuticular slides representing a number of plant groups, complemented by published data to infer biomass accumulation as potential kerogen in the geological column. In addition, (2) from select pinnules of the two species mentioned, nine secretory products and four surrounding cuticles were analyzed by micro-FTIR to evaluate statistically (PCA) the chemotaxonomic potential, and the kerogen chemistry. Further studies in support of (1) or (2) included methods of NICI, SEM, TEM and AFM, and by EDS.Results indicate that the secretory organs occurred in the entire N. ovata frond, its associate petiole and trunk, and in great abundance on the pinnules of both species in a random fashion. Secretory products show layering effects, surfaces can be intact, convoluted, folded, or damaged. At 100,000 magnification, microstructures are not observable. The exact chemical composition is unknown because of insolubility. IR spectra show peaks of functional groups frequently found in isocyanates, disubstituted alkynes, nitriles, polyynes, thiocyanates, and allenes, in part underpinned by EDS results. These compounds were presumably derived from the diagenetic alteration of resin-like terpenoid- or phenolic-related structures. That is particularly the case for the polyynes (i.e. ‘polyacetylenes’), synthesized by living plants with a variety of biological functions, including pigments and flavorings, toxins, and chemical repellents.The chemical information of the lipoid exudate, together with their morphological information and distribution will contribute to (i) the progress of chemotaxonomy and systematics of plant fossils, and (ii) a better understanding of the genesis of kerogens from plant-derived materials, particularly resinous remains.

3D chemical map and a theoretical life model for Neuropteris ovata var. simonii (index fossil, Asturian, Late Pennsylvanian, Canada)

The largest known 65-cm frond segment of Neuropteris ovata var. simonii (Order: Medullosales) from the Late Pennsylvanian of Sydney Coalfield, Canada, is preserved as compression and naturally macerated cuticle and comprises the study sample. The study objectives included (i) analyzing the chemical variability throughout the frond, (ii) interpreting chemical differences in the lower from the upper part of the frond (impossible to do from fragmented specimens), (iii) inferring the likely biopolymeric make-up of the tissues of the once-living plant, (iv) estimating the likely metabolic cost of plant tissue production, and (v) suggesting autecological aspects.The chemical variables (functional groups), obtained by Fourier transform infrared (FTIR) spectroscopy, are interpreted by principal component analysis (PCA) where three PCs explain 89.9% cumulative variance. In effect, this chemometric analysis of functional groups, which is named the 3D chemical map, constitutes a first-time study of a three-dimensional component space in medullosalean frond architecture.The 3D chemical map revealed new insights into relative contributions and distributions of aliphatic, aromatic, and oxygen-containing functional groups from which minimal diagenetic alteration was inferred. The proposed life model for the Sydney ovata plant is summarized as follows: (i) continuous variations of functional-group ratios from lower to upper frond parts are reflective of the continuous variation of foliar morphology (including the corresponding plant tissues), and thus frond architecture (ii) compounds likely related to tannins, lignins, and resins are proposed as the tissue biopolymers of the once-living frond, and (iii) comparison of average bond energy data of the functional groups allowed insights into the metabolic cost of tissue production, where the robust and stiffer lower part of the frond was metabolically more expensive than the slender and more flexible upper part. Inferred is that tannins, and resins were also factors in the chemical defenses against herbivory, and that the ovata plant was an opportunistic colonizer of flood-disturbed sites likely characterized by nitrogen-deficient soils and full-sun conditions.Generalization extending to the ovata species (population) is hypothesized.The use and results of the 3D chemical map introduced a paradigmatic shift into Carboniferous plant studies with profound implications for circumscribing more realistically species and their reconstructions of whole-plants as well as their autecology and synecology.

Chemometric study of structural groups in medullosalean foliage (Carboniferous, fossil Lagerstätte, Canada): Chemotaxonomic implications

A larger chemometric study (data derived from Fourier transform infrared spectroscopy-FTIR interpreted by principal component analysis) is undertaken involving species (numbers bracketed) from the four medullosalean families Neurodontopteridaceae (7), Potonieaceae (1), Cyclopteridaceae (1), and Alethopteridaceae (1). Samples originated from the fossil Lagerstätte ("medullosalean forest") in the Late Pennsylvanian of Sydney Coalfield, Nova Scotia, Canada, where they are preserved as compressions or fossilized-cuticles. The study aims at demonstrating how the level of objectivity for medullosalean fossil-plant determinations can be raised through inquiring (i) if the chemistry of isolated foliage supports the specific classification based on morphologies alone, (ii) if chemistry of different preservation states hampers the application of chemometrics, and (iii) if taxonomic assignation of poorly preserved specimens can be assisted by chemometrics. Given the similar thermal history, direct chemical comparisons amongst taxa having the same preservation state were possible. The chemometric approach resulted into a two principal-component model (80% cumulative-explained variance) that provided information on the relative contributions of aromatic structures, oxygen-containing, and aliphatic groups. These functional groups enabled statistical distinction amongst most of the morphology-defined species, and families, irrespective of the two preservation states. We concluded that results, overall, support the aims of the study, with implications to solve some palaeobotanical difficulties related to biostratigraphy and palaeobiogeography.

Morphology and histochemistry of coalified Trigonocarpus grandis (Sydney Coalfield, Canada): Implications for the preservation, chemotaxonomy, and evolution of Carboniferous medullosalean ovules

From seven of the eight studied coalified ovules (Trigonocarpus grandis: Sydney Coalfield, Canada) sufficient material could be macerated (Schulze's process) for histochemical investigation. This encompasses histological identification of the ovular structure/tissue components by methods of Nomarski phase-contrast microscopy, and determination of the chemical make-up by Fourier transform infrared (FTIR) spectroscopy. The generated data are then input for principal component analysis (PCA), based on the chemometric approach. Not included in PCA, but complementary to it, are data from pyrolysis gas chromatography/mass spectrometry (Py-GC/MS), powder X-ray diffraction, carbon 13 magnetic resonance analyses (13CNMR), and introducing mass spectrometric data of selected epidermal/nucellar and vitrain samples. Addressed amongst other questions are evolution of ovular chemical grouping which includes vitrain and cutin; if coalified ovules reflect optimally original Carboniferous seeds, and why; and can chemotaxonomy/systematics of medullosalean ovules be advanced through histochemistry?Demonstrably preserved in T. grandis are outer and inner integumentary epidermises, a double-walled nucellus with nucellar cuticles, and endospermous tissue. These structures are protected by tecta or nucellar cuticles. Molecular structures for epidermises and nucellii are probably not the same which is suggested by initial mass-spectrometric experiments. These “hard” parts are most resistant to diagenetic influences, correlating with aliphatic (lipid) composition, but facies changes influenced fossilization as in ovular molds/casts vitrain lost all its otherwise preserved tissues. This collectively suggests a narrow window of fossilizing conditions by coalification. Inferred from PCA are transitional changes, rather than sharp delineation, where the nucellus occupies a chemical composition intermediate between epidermis/cutin and the vitrain. Integumentary fibers, tectum, inorganic replacement of an epidermis, and some nucellar specimens are difficult to group by PCA. Nucellar material is probably suited for chemotaxonomic/systematic research because of the lipid chemistry.

Spectrochemical study of coalified Trigonocarpus grandis (Pennsylvanian tree-fern ovule, Canada): Implications for fossil–organ linkage

Five coalified ovules of the type Trigonocarpus grandis are investigated four of which co-occur with tree-fern foliage Alethopteris pseudograndinioides in the medullosalean forest (basal Cantabrian), and the fifth occurs in top Asturian D (Sydney Coalfield, Canada). Addressed are questions of variability (what is a coalified ovule?), comparison with petrified ovules, pyrolysates and the original make-up of the grandis seeds, and can similar chemistry proxy for organic connection between ovule and foliage?The results demonstrate variable preservation quality despite similar thermal-maturity levels in the geological interval in which the ovules were collected. Nevertheless, the proposed T. grandis model is based on evidence from epidermises associated with inner and outer integuments, and a two-layered nucellus with granulose exine that is covered by a diaphanous layer (tectum?) and nucellar cuticle. The latter separates the inner cuticle of the inner integumentary surface from the megaspore membrane. Parenchymatous and sclerenchymatous cell structures are rare, whereas evidence for integuments, vasculature, and sclerotesta is equivocal. Overall, these features compare with petrified seeds.13C nuclear-magnetic resonance analysis suggests that the A. pseudograndinioides tree fern bore T. grandis seeds. Pyrolysates from low and high molecular weights can almost exclusively be grouped with alkenes and aromatics; phenolics, furan and branched alkenes; and with n-alkene/n-alkane homologous series (~3 to 1) for cuticles from the inner integumentary surface which suggests a cutin-based, aliphatic-rich biomacromolecule. More generally, preservation is presumed correlative with aliphatic content, but not exclusively, and organ–organ linkage by spectrochemical means certainly has potential as a new research vector in palaeobotany.

Powder X-ray diffraction and X-ray photoelectron spectroscopy of cutin from a 300 Ma tree fern (Alethopteris pseudograndinioides, Canada)

Experimental results of X-ray diffraction and X-ray photoelectron spectroscopy of fossil cutin from the compressed foliage of the Carboniferous tree fern Alethopteris pseudograndinioides, Cantabrian age, Sydney Coalfield, Canada, are presented in this paper. The light-colored cutin was obtained by oxidizing the compression in Schulze's solution in two stages for a total of 19days. The broad peak in the powder diffractogram at 20° is characteristic of an average separation of ~4.4Å between the methylenic hydrocarbon chains (CH2)n, whereas the sharper peaks at 26°–28° suggest that within a small fraction of the sample, the chains are more regularly separated. Most of the chains are likely randomly aligned to form a nematic structure.Elemental composition by mass amounts to 58.3% C, 1.1% N, 19.4% O, 19.7% Cl, and 1.5% Si, and the local chemical environment of C 1s, O 1s, and Cl 2p is probed. Cl content is a surprising result, and further research is needed for identifying chlorine-containing species.

Lepidodendron dawsonii: functional groups and pyrolysates of compression and fossilized-cuticle (Late Asturian, Canada)

Lepidodendron dawsonii BELL 1938 is an endemic species of Late Asturian age in the Canadian Sydney Coalfield, with conspicuous elongate leaf cushions. The study specimen, 35 cm long and 10 cm wide, represents a dichotomous bough from the tree crown in which the inner part of one side is black and compression-preserved, whereas the one in contact with the entombing rock matrix is dark-amber in colour and fossilized-cuticle preserved. Only stomatal pits and cuticular details are preserved. Comparison of these preservation states, based on Fourier transform infrared (FTIR) spectrometry, and flash pyrolysis gas chromatography mass spectroscopy (Py-GC/MS), demonstrate sufficient differences in chemistry to be able to link the two preservation states with differing pathways of organic matter transformation (diagenesis). The aliphatic-hydrocarbon chains of the cuticles are comparatively shorter and more branched than the longer chains of the compressions. Py-GC/MS results support the presence of hydrocarbon markers of plant cuticles. The high abundances of C1 and -C2 alkylphenols and C1 and -C2 alkylbenzenes in pyrolysates are likely derived from maturing lignin or lignin-like biomacromolecules. We suggest comparison of L. dawsonii’s cuticles with Lepidodendron coal macerals in Chinese Permian Leping coal, and with suberinite.

Fossil cutin of Macroneuropteris scheuchzeri (Late Pennsylvanian seed fern, Canada)

Cutin polymer from compression-preserved specimens of Macroneuropteris scheuchzeri (seed fern, Medullosales) is recorded for the first time. Specimens of basal Cantabrian strata, Sydney Coalfield, Canada, exhibit excellent preservation. The cutin was concentrated by Schulze's process by time-controlled oxidation reaction. Reported are functional-group changes monitored via semi-quantitative Fourier transform infrared (FTIR) spectrometry as a function of cutin concentration in Schulze's solution. Distinct features of the cutin spectrum include intense peaks of ester CO groups, centered at 1730–1715cm−1, and aromatic CC absorption bands at 1640–1645cm−1. Cutin is characterized and differentiated from the corresponding M. scheuchzeri cuticle mainly by the comparatively higher values of CH2/CH3, CO/CC, and the very low values of CHal/CO and CC contribution. Cutin data compare with available semi-quantitative FTIR data from modern L. esculentum cutin, particularly emphasized by CHal/CO ratios whose low value of ca. 0.9 indicates a similar cross-linking degree of the polymeric structure for the fossil and extant taxa.

Chemometric study of functional groups in different layers of Trigonocarpus grandis ovules (Pennsylvanian seed fern, Canada)

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 7–8 cm 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.

Palynological evidence for Pennsylvanian extra-basinal vegetation in Atlantic Canada

Abstract: Pollen preserved in latest Westphalian and early Stephanian clastic deposits of the Sydney Coalfield, Cape Breton Island, suggest that there were zones of different vegetational habitats surrounding the wetlands where the coal-forming peat was formed. On the margins of the wetlands was a narrow band with large cordaitanthacean trees. This was surrounded by ‘occasionally dry' habitats supporting Schuetzia -plants, ruflorioid-plants and Aethophyllum -like herbaceous conifers. Around this were mesic or seasonally dry habitats, dominated by walchian conifers and disaccate-producing peltasperms. These in turn were surrounded by xeric or seasonally wet habitats, dominated by ullmanniacean-like conifers, cycads and monosaccate-producing peltasperms. During latest Westphalian and early Stephanian times, the mesic and xeric habitats encroached nearer the wetlands, although the vegetation of the wetlands themselves remained essentially unaffected. This vegetation change was not a response to climate change, but probably to changing drainage patterns and topography in the surrounding hinterland. The Florinites -producing cordaitanthaceans appear not to have been upland trees, as previously suggested, but occupied mainly coastal habitats, or riparian habitats on the margins of the wetlands.

Chemometric study of functional groups in Pennsylvanian gymnosperm plant organs (Sydney Coalfield, Canada): Implications for chemotaxonomy and assessment of kerogen formation

The samples comprise the foliage of four pteridosperm-medullosalean plant-fossil species of differing preservation states and one of a cordaitean species from two Canadian Maritime sub-basins of Carboniferous age (300 Ma; Sydney and Stellarton coalfields, Nova Scotia, respectively. Included in the sample set were some coal samples from Sydney Coalfield, along with published data for coal macerals for comparison. By applying Schulze’s maceration process to the fossil foliage to obtain the cuticles, five sample forms evolved, viz. compressions, cuticles and fossilized cuticles, and acidic and alkaline solutions from Schulze’s process, to which was added the Sydney coal samples as the sixth form. Area integration of the absorbance spectra from solid and liquid state Fourier transform infrared (FTIR) spectroscopy, produced functional chemical parameters which were organized into a data matrix of eight variables and 62 samples (8 x 62 matrix). Since we were interested in grouping the sample forms as a function of phytochemistry (functional groups) to assess primarily the palaeophytotaxonomic potential as a general approach to Carboniferous taxonomy, principal components were extracted from the matrix, and a subset of 4 x 33 samples in order to refine the grouping results from the initial component analysis. In either case, a two component model resulted, accounting for least 80% of the cumulative variance in either case. Overall, the results are encouraging in offering increasing support for fossil-leaf chemotaxonomy, but bearing in mind the limited sampling number (56) and restricted sampling of genera (5). Apart from this general conclusion, which supports our previous FTIR work vis-à-vis chemotaxonomy, we noted functional-group similarities in our FTIR data with types of kerogen and coal macerals. On this basis, we hypothesize that, in combination with the different preservation states of our fossil specimens, these factors have a bearing on kerogen genesis from plant material, i.e. the oil and gas prone Types I and II.

Phytochemistry of the fossilized-cuticle frond Macroneuropteris macrophylla (Pennsylvanian seed fern, Canada)

Abstract In Canada's Sydney Coalfield, specimens of the extinct Carboniferous seed fern Macroneuropteris macrophylla (Brongniart) invariably show preservation stages intermediate between compression and fossilized-cuticle, even concerning a single pinnule. In this interdisciplinary approach, we study a ca. 300 to 350 mm long fossilized-cuticle-preserved frond section of M. macrophylla (Brongniart) that represents about one third of the length of a frond that was originally 1 m long. Size and preservation allow us to study the phytochemistry of the cuticle biomacropolymers over the length of the frond to assess what impact, if any, results would have on Carboniferous palaeophytochemotaxonomy. For comparison, the phytochemistry of compressions with their extracted cuticles from the same species and the same sample locality is also investigated. We use solid- and liquid-state, semi-quantitative Fourier transform infrared spectroscopy (FTIR) for the chemical characterization of the frond. Based on our results, we infer an essentially uniform phytochemistry over the fossilized-cuticle frond, suggesting that only a single pinnule needs to be analyzed to get an overall phytochemical picture of the frond, which has been our long-time working hypothesis. We distinguish between phytochemistry and cutinization. The latter is much less pronounced above than below the frond dichotomy, and we suggest a palaeoecological cause, rather than differing pathways of organic matter transformation. Moreover, cuticles below and above the frond dichotomy have essentially the same epidermal pattern, but those from below have features that may have been an adaptation to prevent stomatal flooding during the tropical, rainy season. This study suggests that chemically the fossilized-cuticle is more similar to the compression than to the cuticle obtained from that compression of the same species which invites reevaluation of the classical compression concept.

Palynological evidence for Pennsylvanian (Late Carboniferous) vegetation change in the Sydney Coalfield, eastern Canada

AbstractThe palynology of clastic samples from seven stratigraphical levels in the late Moscovian Sydney Mines Formation, exposed along the shore at Bras d'Or, Nova Scotia, has been investigated. Most of the samples were from roof shales of major coals; the one sample that was not yielded a much higher proportion of pollen derived from extra‐basinal vegetation. The four stratigraphically lower roof shale samples yielded essentially similar palynological spectra, with 39 ± 4% lycophytes, 9 ± 4% sphenophylls, 23 ± 4% tree‐ferns, 12 ± 4% other ferns and 5 ± 3% cordaites. The palynology of the upper part of the investigated succession suggests a shift in vegetation towards one favouring more marattialean tree‐ferns, cordaites and conifers, and fewer lycophytes. This correlates with changes in drainage patterns as the alluvial plain migrated seawards and thus changed water tables. No evidence was found to suggest significant climate change at this time. Copyright © 2009 John Wiley &amp; Sons, Ltd.

Medullosalean fusain trunk from the roof rocks of a coal seam: Insight from FTIR and NMR (Pennsylvanian Sydney Coalfield, Canada)

Reported for the first time from the Sydney Coalfield, Canada, is a fragmentary fusain (Ro = 2.51%) specimen, 41 cm long, of a medullosalean trunk or massive petiole that originated from the roof rocks of the banded bituminous Hub Seam (Ro ∼ 0.65%). Megascopic characteristics of the flat-preserved specimen include an irregular-cracked fusain surface with secretinite–rodlet structures and sclerenchymatous strands some of which still embedded in the shaly matrix, and locally preserved vitrain (Ro = 0.69%). Co-occurrence with a compression flora composed virtually of only the seed-fern taxon Macroneuropteris scheuchzeri (Hoffmann) is noted. The goal of this study is to provide a framework for the phytophysicochemical taphonomic history which includes the perspective on vitrinite/fusinite relationship, formation of fusinite, and on the significance the only fusinized identifiable plant-fossil specimen in the Sydney Coalfield. We use state-of-the-art solid-state FTIR, 13C, 1H NMR CP/MAS techniques, and standard reflected-light microscopy and SEM methods as investigative tools. Results indicate that the fusinite is characterized by long and narrow xylem fibers, without fungal signals, and cell structures infilled with pyrite and carbonate. FTIR spectra of the fusinite and secretinite are similar particularly in respect to high absorbance of aromatic and low absorbance of aliphatic compounds, and absorbance of Si–O functionalities relating to kaolinite. 13C NMR experiments with direct carbon excitation quantify the aromatic to aliphatic ratio as being 20 ± 3:1. As part of the taphonomic history, the evidence favors a hot, > 400 °C, directional surface-fueled flame palaeofire of local extent that charred trunks of growing arborescent seed ferns on only one side, and that these trunks were transported to comprise part of the roof rocks of the Hub Seam.

A proposed origin for fossilized Pennsylvanian plant cuticles by pyrite oxidation (Sydney Coalfield, Nova Scotia, Canada)

A proposed origin for fossilized Pennsylvanian plant cuticles by pyrite oxidation (Sydney Coalfield, Nova Scotia, Canada)

06/02904 Colliery and surface hazards through coal-pyrite oxidation (Pennsylvanian Sydney Coalfield, Nova Scotia, Canada)Zodrow, E. L. International Journal of Coal Geology, 2005, 64, (1–2), 145–155

06/02904 Colliery and surface hazards through coal-pyrite oxidation (Pennsylvanian Sydney Coalfield, Nova Scotia, Canada)Zodrow, E. L. International Journal of Coal Geology, 2005, 64, (1–2), 145–155