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Lakeram Scott - One of the best experts on this subject based on the ideXlab platform.
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Cordaitean Predation Photos 2019: Unmounted Peels, Wild Cones. Plate 1C
Texas A&M University. Libraries, 2020Co-Authors: Lakeram ScottAbstract:These images were used in the research for a master's thesis from the Texas A&M University Dept. of Geology and Geophysics (Date of submission: May 2020).Images were taken from unmounted peels of Coal Balls.Cones A, B and C are basal sections.Cones D and E are degraded cones.Peels were made by Anne Raymond, the advisor for this thesis.Cone maturity is as follows- cone A, basal section (picture 1, top left); cone B, basal section (picture 1, top, right); cone C, basal section (picture 2, left); cone D, taphonomically degraded (picture 2, right); cone E, taphonomically degraded (picture 3). Plate 1C is a successive peel taken from the same Coal Ball as other plates labeled 1
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Cordaitean Predation Photos 2019: Unmounted Peels, Wild Cones. Plate 1A
Texas A&M University. Libraries, 2020Co-Authors: Lakeram ScottAbstract:These images were used in the research for a master's thesis from the Texas A&M University Dept. of Geology and Geophysics (Date of submission: May 2020).Images were taken from unmounted peels of Coal Balls.Cones B and C are immature cones.Cone A is a basal section.Peels were made by Anne Raymond, the advisor for this thesis.Cone maturity is as follows- cone A, basal section (picture 1); cone B, immature (picture 2); cone C, immature (picture 3). Plate 1A is a successive peel taken from the same Coal Ball as other plates labeled 1
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Cordaitean Predation Photos 2019: Unmounted Peels, Wild Cones. Peel 19A
Texas A&M University. Libraries, 2020Co-Authors: Lakeram ScottAbstract:These images were used in the research for a master's thesis from the Texas A&M University Dept. of Geology and Geophysics (Date of submission: May 2020).Images were taken from unmounted peels of Coal Balls.Cone A is an mature coneCone B and C are basal sections.Peels were made by Anne Raymond, the advisor for this thesis.Cone maturity is as follows- cone A, mature (picture 1); cone B, basal section (picture 2, left); cone C, basal section (picture 2, right). Cone A contained a single golden coprolite within its scales. Plate 19A is a successive peel taken from the same Coal Ball as other plates labeled 19
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Cordaitean Predation Photos 2019: Unmounted Peels, Wild Cones. Peel 19C
Texas A&M University. Libraries, 2020Co-Authors: Lakeram ScottAbstract:These images were used in the research for a master's thesis from the Texas A&M University Dept. of Geology and Geophysics (Date of submission: May 2020).Images were taken from unmounted peels of Coal Balls.Cones A and D matureCones B, C and E are basal sections.Peels were made by Anne Raymond, the advisor for this thesis.Cone maturity is as follows- cone A, mature (picture 1); cone B, basal section (picture 2, left); cone C, basal section (picture 3, bottom left); cone D, mature (picture 3, bottom left); cone E, basal section (picture 3, top right). Cone D contains a large pollen mass in the cone. Plate 19C is a successive peel taken from the same Coal Ball as other plates labeled 19
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Cordaitean Predation Photos 2019: Unmounted Peels, Wild Cones. Plate 17B
Texas A&M University. Libraries, 2020Co-Authors: Lakeram ScottAbstract:These images were used in the research for a master's thesis from the Texas A&M University Dept. of Geology and Geophysics (Date of submission: May 2020).Images were taken from unmounted peels of Coal Balls.Cone A is a mature cone containing a golden coproliteCone B is a degraded cone.A brown coprolite was identified in the matrix.Peels were made by Anne Raymond, the advisor for this thesis.Cone A (picture 1) is a mature cordaitean cone and cone B (picture 2) is taphonomically degraded. A golden coprolite was identified in proximity to cone A (picture 1) and a single brown coprolite was identified in the matrix (picture 3). Plate 17B is a successive peel taken from the same Coal Ball as plate 17A
Jean Galtier - One of the best experts on this subject based on the ideXlab platform.
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The fern Stauropteris oldhamia Binney: New data on branch development and adaptive significance of the hypodermal aerenchyma
Comptes Rendus Palevol, 2014Co-Authors: Maryam Farahimanesh, Jean Galtier, Philippe Gerrienne, Cyrille PrestianniAbstract:International audienceWell-preserved specimens of Stauropteris oldhamia are described. The material was collected in the early 1920s from the Lower Westphalian (Early Pennsylvanian) Saurue seam from Belgium. The fossil plants occur as permineralized axes fragments within a Coal Ball. This study confirms most of the interpretations made by previous researchers. The observation of immature axis however suggests a less regular organization than previously interpreted beyond the three first branching orders. We also highlight the presence of profusely and dichotomously branched aphlebiae, the lack of laminate organs as well as the presence of hypodermal aerenchyma in all plant parts. We interpret these features as part of a very specialized assimilatory apparatus indicating an adaptation to a humid swamp environment
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The fern Stauropteris oldhamia Binney: New data on branch development and adaptive significance of the hypodermal aerenchyma
Comptes Rendus Palevol, 2014Co-Authors: Farahimanesh Maryam, Jean Galtier, Philippe Gerrienne, Cyrille PrestianniAbstract:Well-preserved specimens of Stauropteris oldhamia are described. The material was collected in the early 1920s from the Lower Westphalian (Early Pennsylvanian) Saurue seam from Belgium. The fossil plants occur as permineralized axes fragments within a Coal Ball. This study confirms most of the interpretations made by previous researchers. The observation of immature axis however suggests a less regular organization than previously interpreted beyond the three first branching orders. We also highlight the presence of profusely and dichotomously branched aphlebiae, the lack of laminate organs as well as the presence of hypodermal aerenchyma in all plant parts. We interpret these features as part of a very specialized assimilatory apparatus indicating an adaptation to a humid swamp environment.
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General palaeontology, systematics and evolution (Palaeobotany) The fern Stauropteris oldhamia Binney: New data on branch development and adaptive significance of the hypodermal
2014Co-Authors: Maryam Farahimanesh, Jean Galtier, Philippe Gerrienne, Cyrille PrestianniAbstract:a b s t r a c t Well-preserved specimens of Stauropteris oldhamia are described. The material was col- lected in the early 1920s from the Lower Westphalian (Early Pennsylvanian) Saurue seam from Belgium. The fossil plants occur as permineralized axes fragments within a Coal Ball. This study confirms most of the interpretations made by previous researchers. The obser- vation of immature axis however suggests a less regular organization than previously interpreted beyond the three first branching orders. We also highlight the presence of pro- fusely and dichotomously branched aphlebiae, the lack of laminate organs as well as the presence of hypodermal aerenchyma in all plant parts. We interpret these features as part of a very specialized assimilatory apparatus indicating an adaptation to a humid swamp
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Early Permian silicified floras from the Perdasdefogu Basin (SE Sardinia): comparison and bio-chronostratigraphic correlation with the floras of the Autun Basin (Massif central, France)
Geodiversitas, 2011Co-Authors: Jean Galtier, Ausonio Ronchi, Jean BroutinAbstract:ABSTRACT In the Perdasdefogu Basin (Ogliastra, Sardinia) plants occurring in angular cherts are preserved as siliceous permineralizations. The plant assemblage consists of the genera Sphenophyllum, Arthropitys, Astromyelon, Palaeostachya, Pecopteris, Scolecopteris, Stewartiopteris, Psaronius, Ankyropteris, Anachoropteris; furthermore, probable medullosan wood and ovules, cordaitean stems, leaves and ovules, and Dadoxylon wood have been recorded. Arborescent marratialean ferns are the dominant elements with Pecopteris and Scolecopteris leaves being the most common; the calamiteans are the second in abundance. Generally the chert blocks contain a large number of plant fragments — roots and leaves are being almost equally represented — suggestive of a Coal Ball-like plant accumulation. More rarely a chert block may consist of a single plant part, for example a piece of wood. The preservation and accumulation of the plants are closely comparable to the silicified plant assemblages described from the Lower Per...
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Coal Ball floras of the namurian westphalian of europe
Review of Palaeobotany and Palynology, 1997Co-Authors: Jean GaltierAbstract:Abstract A review of Coal-Ball floras from Central and Western Europe is presented with special attention to recent studies of Coal Balls from England and Spain. Emphasis is placed on the stratigraphic and geographic distribution of taxa, and on a comparison of twelve floras including those of the Late Carboniferous “Great Coal Ball Horizon”, as well as two of Namurian age from the Czech Republic and Germany, and one new flora from Spain. The three richest floras include those from the Upper Foot and Union seams (Lancashire, UK) and Bouxharmont (Belgium). These differ in taxonomic diversity, relative to the number of species of gymnosperms, lycopsids and ferns. Patterns of occurrences of taxa for each major group of plants are discussed and compared with quantitative data provided recently for some floras by T.L. Phillips and colleagues. The significance of common versus rare taxa is discussed, and a list of species is proposed as most representative of Westphalian European Coal-swamp associations. Comparison of the very different temporal ranges of about 40 important genera suggest that, since the Mississippian, there existed a sequential introduction from non-swamp habitats of plants that became abundant/dominant in later Euramerican Coal swamps.
Gary E. Maciel - One of the best experts on this subject based on the ideXlab platform.
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Coalification of organic matter in Coal Balls of the Pennsylvanian (upper Carboniferous) of the Illinois Basin, United States
Organic Geochemistry, 2003Co-Authors: Paul C. Lyons, Patrick G Hatcher, Carolyn L. Thompson, Floyd W. Brown, Michael A. Millay, Nikolaus M. Szeverenyi, Gary E. MacielAbstract:Abstract An evaluation was made of the degree of Coalification of two Coal Balls from the Illinois Basin of the Pennsylvanian (upper Carboniferous) of the United States. Previous interpretations are mainly misleading and contradictory, primarily because of the assumption that the brown color and exceptional cellular and subcellular preservation typical of American Coal Balls imply chemical preservation of cellulose and lignin, the primary components of peat. Xylem tissue from a medullosan seed fern contained in a Coal Ball and the Coal attached to the Coal Ball from the Calhoun Coal bed, Mattoon Formation, Illinois, was analyzed by elemental, petrographic, and nuclear magnetic resonance (NMR) techniques to determine the degree of Coalification. The NMR and elemental data indicate the lack of cellulose and lignin and a probable rank of high-volatile C bituminous Coal. These data corroborate data for a Coal Ball from the Herrin (No. 6) Coal bed (Carbondale Formation, Middle Pennsylvanian) and support our hypothesis that the organic matter in Coal Balls of the Pennsylvanian strata of the United States is Coalified to about the same degree as the surrounding Coal. Data presented show a range of lower reflectances for xylem tissue and vitrinite in the analyzed Coal Balls compared with vitrinite in the attached Coal. The data reported indicate that physical preservation of organic matter in Coal Balls does not imply chemical preservation. Also our study supports the hypothesis that compactional (static load) pressure is not a prerequisite for Coalification up to a rank of high-volatile C bituminous Coal. A whole-rock analysis of the Calhoun Coal Ball indicates a similarity to other carbonate Coal Balls from the United States. It consists primarily of calcium carbonate and 1–2% organic matter; silica and alumina together make up less than 0.5%, indicating the lack of minerals such as quartz and clays.
Paul C. Lyons - One of the best experts on this subject based on the ideXlab platform.
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Coalification of organic matter in Coal Balls of the Pennsylvanian (upper Carboniferous) of the Illinois Basin, United States
Organic Geochemistry, 2003Co-Authors: Paul C. Lyons, Patrick G Hatcher, Carolyn L. Thompson, Floyd W. Brown, Michael A. Millay, Nikolaus M. Szeverenyi, Gary E. MacielAbstract:Abstract An evaluation was made of the degree of Coalification of two Coal Balls from the Illinois Basin of the Pennsylvanian (upper Carboniferous) of the United States. Previous interpretations are mainly misleading and contradictory, primarily because of the assumption that the brown color and exceptional cellular and subcellular preservation typical of American Coal Balls imply chemical preservation of cellulose and lignin, the primary components of peat. Xylem tissue from a medullosan seed fern contained in a Coal Ball and the Coal attached to the Coal Ball from the Calhoun Coal bed, Mattoon Formation, Illinois, was analyzed by elemental, petrographic, and nuclear magnetic resonance (NMR) techniques to determine the degree of Coalification. The NMR and elemental data indicate the lack of cellulose and lignin and a probable rank of high-volatile C bituminous Coal. These data corroborate data for a Coal Ball from the Herrin (No. 6) Coal bed (Carbondale Formation, Middle Pennsylvanian) and support our hypothesis that the organic matter in Coal Balls of the Pennsylvanian strata of the United States is Coalified to about the same degree as the surrounding Coal. Data presented show a range of lower reflectances for xylem tissue and vitrinite in the analyzed Coal Balls compared with vitrinite in the attached Coal. The data reported indicate that physical preservation of organic matter in Coal Balls does not imply chemical preservation. Also our study supports the hypothesis that compactional (static load) pressure is not a prerequisite for Coalification up to a rank of high-volatile C bituminous Coal. A whole-rock analysis of the Calhoun Coal Ball indicates a similarity to other carbonate Coal Balls from the United States. It consists primarily of calcium carbonate and 1–2% organic matter; silica and alumina together make up less than 0.5%, indicating the lack of minerals such as quartz and clays.
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Discovery of permineralized plant fossils (Coal Balls) in the Bolsovian (e.g., Westphalian C) (Middle Pennsylvanian, Upper Carboniferous), Stellarton Basin, Nova Scotia, Canada
Canadian Journal of Botany, 1995Co-Authors: Paul C. Lyons, Michael A. Millay, Erwin L. Zodrow, Aureal T. Cross, Kevin S. GillisAbstract:Permineralized plant fossils (Coal Balls) of Bolsovian age (ex Westphalian C) were discovered in the Foord seam of the Stellarton Basin of Nova Scotia. The Coal-Ball plants were preserved in a siderite–dolomite matrix and formed in a nonmarine intermontane setting. The Coal-Ball flora is dominated by arborescent lycopods and contains a few ferns, as well as occasional seed ferns, calamiteans, and cordaiteans. The following taxa were identified: Diaphorodendron, Paralycopodites brevifolia, Lepidocarpon lomaxii, Stigmaria, Scolecopteris, Botryopteris tridentata, Medullosa, Heterangium, Astromyelon, and Cordaianthus. This assemblage contains plants typical of Westphalian Coal-swamp floras and helps fill a stratigraphie gap in Westphalian Coal-Ball floras of Euramerica. Key words: permineralized plants, Coal Balls, Carboniferous, Canada.
Tom L. Phillips - One of the best experts on this subject based on the ideXlab platform.
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petrography and microanalysis of pennsylvanian Coal Ball concretions herrin Coal illinois basin usa bearing on fossil plant preservation and Coal Ball origins
Sedimentary Geology, 2015Co-Authors: Fredrick D Siewers, Tom L. PhillipsAbstract:Abstract Petrographic analyses of 25 Coal Balls from well-studied paleobotanical profiles in the Middle Pennsylvanian Herrin Coal (Westphalian D, Illinois Basin) and five select Coal Balls from university collections, indicate that Herrin Coal-Ball peats were permineralized by fibrous and non-fibrous carbonates. Fibrous carbonates occur in fan-like to spherulitic arrays in many intracellular (within tissue) pores, and are best developed in relatively open extracellular (between plant) pore spaces. Acid etched fibrous carbonates appear white under reflected light and possess a microcrystalline texture attributable to abundant microdolomite. Scanning electron microscopy, X-ray diffraction, and electron microprobe analysis demonstrate that individual fibers have a distinct trigonal prism morphology and are notable for their magnesium content (≈ 9–15 mol% MgCO 3 ). Non-fibrous carbonates fill intercrystalline spaces among fibers and pores within the peat as primary precipitates and neomorphic replacements. In the immediate vicinity of plant cell walls, non-fibrous carbonates cut across fibrous carbonates as a secondary, neomorphic phase attributed to Coalification of plant cell walls. Dolomite occurs as diagenetic microdolomite associated with the fibrous carbonate phase, as sparite replacements, and as void-filling cement. Maximum dolomite (50–59 wt.%) is in the top-of-seam Coal-Ball zone at the Sahara Mine, which is overlain by the marine Anna Shale. Coal-Ball formation in the Herrin Coal began with the precipitation of fibrous high magnesium calcite. The trigonal prism morphology of the carbonate fibers suggests rapid precipitation from super-saturated, meteoric pore waters. Carbonate precipitation from marine waters is discounted on the basis of stratigraphic, paleobotanical, and stable isotopic evidence. Most non-fibrous carbonate is attributable to later diagenetic events, including void-fill replacements, recrystallization, and post-depositional fracture fills. Evidence suggests that CO 2 degassing was important in Coal-Ball formation in the Herrin Coal, which mainly occurred sequentially upward with peat accumulation in the sites studied.
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Paleobotany and Palynology of the Bristol Hill Coal Member (Bond Formation) and Friendsville Coal Member (Mattoon Formation) of the Illinois Basin (Upper Pennsylvanian)
PALAIOS, 1993Co-Authors: Debra A. Willard, Tom L. PhillipsAbstract:Late Pennsylvanian Coal swamps of the Illinois Basin were dominated by Psaronius tree ferns with a spatially heterogeneous distribution of medullosan pteridosperms (subdominant), calamites, sigillarian lycopsids, and cordaites. Miospore and Coal-Ball plant assemblages from the Missourian-age Bristol Hill Coal Member (Bond Formation) and Friendsville Coal Member (Mattoon Formation) of southeastern Illinois were quantified to analyze vegetational patterns in Late Pennsylvanian peat swamps and to compare vegetational composition of the Coals. In the Bristol Hill Coal (95 Coal Balls, 2613 cm 2 CoalBall peels), tree ferns are dominant (75.6%), followed by pteridosperms (11.5%), lycopsids (10.6%), sphenopsids (0.6%), small ferns (1.6%), and cordaites (0.1%)