Novel preservation state of Dolerotheca (medullosalean male organ) from the Late Pennsylvanian of the Sydney Coalfield, Nova Scotia, Canada

A new preservation state for the medullosalean male organ Dolerotheca is exemplified by a detached 31-mm sideritic mold with intact coalified compression from shale from the roof of a coal seam in the Sydney Coalfield, Cape Breton Island, Nova Scotia, Canada. Clearly recognizable in the specimen is the quadripartite campanulum. Furthermore, maceration yielded significant internal information on acellular, cuticular, stomatiferous and pubescent surfaces, and prepollen sacs with grains. Stomata are rare and of the cyclocytic type. The rectangular prepollen sacs occur as doubly paired rows of sporangia that are radially arranged, and contain ellipsoidal prepollen grains 400−520 μm long and circular prepollen grains 330−460 μm in diameter. The approximate ratio of circular to ellipsoidal grains is 1:2. Regardless of shape, the prepollen grains are attributable to the genus Monoletes. The circular grains bear vestigial trilete marks. Infrared-based functional-group chemistry distinguishes between the cover-type compression state and prepollen grains on the basis of higher aliphatic and oxygenated group contents in the grains. In summary, the specimen represents a novel state of nodular preservation with intact compression.  Although the specimen is attributed to the genus Dolerotheca, specific assignment is not possible because of limited preservation and material

Compound Specific Carbon and Hydrogen Stable Isotope Ratios of Coalbed Gases in Southeastern Illinois Basin

Presented at the American Association of Petroleum Geologists International Conference and Exhibition, November 5-8, 2006, Perth, West Australia.Coalbed gases and waters from exploratory and production gas wells in the southeastern Illinois Basin were sampled to geochemically assess the origin of coalbed gases, with emphasis on Springfield and Seelyville coal members that are commercially targeted for coalbed methane production. On-line analyses of hydrocarbon gases (methane to butanes: C1, C2, C3, n-C4, i-C4) and CO2 yielded chemical concentrations, Delta-D, and Delta 13C values. The low thermal maturity of Indiana coals (vitrinite reflectance Ro ~ 0.6%) is in agreement with an overwhelmingly biogenic isotopic signature of coalbed gas that has greater than or equal to 96% methane generated via bacterial CO2-reduction. In contrast, thermogenic coalbed gas was generated by the stratigraphically equivalent coalbeds in western Kentucky’s Rough Creek Graben zone where higher maturities of up to Ro ~ 0.8% are reached due to tectonic and hydrothermal activity. No secondary biogenic methane was observed in Kentucky coalbed gases, probably due to greater burial depths and limited recharge of meteoric water. The two differently sourced types of coalbed gases are compositionally and isotopically distinct. Microbial biodegradation of thermogenic C2+ hydrocarbon gases in Indiana coalbeds preferentially targets C3 and introduces isotope fractionation whereby remaining C3 is enriched in heavy hydrogen and carbon isotopes.Supported by U.S. Department of Energy, Basic Energy Research Grant DEFG02-00ER1503

Compound Specific Carbon and Hydrogen Stable Isotope Ratios of Coalbed Gases in Southeastern Illinois Basin

Presented at the American Association of Petroleum Geologists International Conference and Exhibition, November 5-8, 2006, Perth, West Australia.Coalbed gases and waters from exploratory and production gas wells in the southeastern Illinois Basin were sampled to geochemically assess the origin of coalbed gases, with emphasis on Springfield and Seelyville coal members that are commercially targeted for coalbed methane production. On-line analyses of hydrocarbon gases (methane to butanes: C1, C2, C3, n-C4, i-C4) and CO2 yielded chemical concentrations, Delta-D, and Delta 13C values. The low thermal maturity of Indiana coals (vitrinite reflectance Ro ~ 0.6%) is in agreement with an overwhelmingly biogenic isotopic signature of coalbed gas that has greater than or equal to 96% methane generated via bacterial CO2-reduction. In contrast, thermogenic coalbed gas was generated by the stratigraphically equivalent coalbeds in western Kentucky’s Rough Creek Graben zone where higher maturities of up to Ro ~ 0.8% are reached due to tectonic and hydrothermal activity. No secondary biogenic methane was observed in Kentucky coalbed gases, probably due to greater burial depths and limited recharge of meteoric water. The two differently sourced types of coalbed gases are compositionally and isotopically distinct. Microbial biodegradation of thermogenic C2+ hydrocarbon gases in Indiana coalbeds preferentially targets C3 and introduces isotope fractionation whereby remaining C3 is enriched in heavy hydrogen and carbon isotopes

Contact Metamorphism of Bituminous Coal by Intruding Dike in the Illinois Basin Causes Short-Range Thermal Alteration

This poster will be presented at the joint meeting of the Canadian Society for Coal Science and Organic Petrology, The Society for Organic Petrology, and the International Committee for Coal and Organic Petrology at the University of Victoria, Victoria, British Columbia, Canada, on August 19-25, 2007.Changes in high-volatile bituminous coal (Pennsylvanian) near contacts with volcanic intrusions in Illinois were investigated with respect to coal chemistry, carbon and hydrogen stable isotope ratios, and pore structure. Vitrinite reflectance (Ro) increases from ~0.6% to ~5% within 4.7 m from the dike. Elemental chemistry of the coal shows distinct reduction in hydrogen and nitrogen content approaching the intrusions. No trend was noticed for total sulfur content, but decreases in sulfate and organic sulfur contents towards the dikes indicate thermal sulfur reduction (TSR). Carbon isotopic values did not show significant changes, whereas hydrogen isotopic values showed a distinct trend of becoming more negative toward the dikes. Contact metamorphism has a dramatic effect on coal porosity. The mesopore volume decreases 3 3 from 0.01 cm /g in the unaffected coal to 0.004 cm /g at a distance 3 of 4.5 m away from the contact, then hovers around 0.004 cm /g closer to the contact. In contrast, the micropore volume shows a 3 progressive decrease from 0.04 cm /g in unaffected coal to almost 3 0.01 cm /g at the contact. Strongly decreasing mesopore and micropore volumes in the altered zone, together with frequent cleat and fracture-filling by calcite, indicate deteriorating conditions for both coalbed gas sorption and gas transmissibility

Organic Geochemistry and Petrology of Oil Source Rocks, Carpathian Overthrust Region, Southeastern Poland — Implications for Petroleum Generation

The organic matter rich Oligocene Menilite black shales and mudstones are widely distributed in the Carpathian Overthrust region of southeastern Poland and have excellent hydrocarbon generation potential, according to TOC, Rock-Eval, and petrographic data. Extractable organic matter was characterized by an equable distribution of steranes by carbon number, by varying amounts of 28,30-dinor-hopane, 18α(H)-oleanane and by a distinctive group of C24 ring-A degraded triterpanes. The Menilite samples ranged in maturity from pre-generative to mid-oil window levels, with the most mature in the southeastern portion of the study area. Carpathian petroleum samples from Campanian-Oligocene sandstone reservoirs were similar in biomarker composition to the Menilite rock extracts. Similarities in aliphatic and aromatic hydrocarbon distributions between petroleum asphaltene and source rock pyrolyzates provided further evidence genetically linking Menilite kerogens with Carpathian oils

Organic Geochemistry of Permian Organic-rich Sediments from the Sudetes Area, SW Poland

Lacustrine and marine sediments from the Permian rift-basins of southwestern Poland were analysed using GC-MS and petrographic techniques. High Pr/Ph ratios, gamma- and beta-carotanes and gammacerane in the lacustrine sediments indicate deposition under elevated water salinities. The primary organic matter is represented by bacterial and algal lipids with variable terrestrial input. Marine algal lipids with minor bacterial and cyanobacterial lipids are the primary source of organic matter in the marine sediments. Extended hopanes, n-alkanes with even-odd predominance and low Ts/Tm ratios are consistent with deposition in a closed, evaporitic basin with substantial carbonate sedimentation

Migmatite-Like Textures in Anthracite: Further Evidence for Low-Grade Metamorphic Melting and Resolidification in High-Rank Coals

Previous studies demonstrated that melting, initiated by supercritical fluids in the 375–400 °C range, occurred as part of anthracite metamorphism in the Appalachian Basin. Based on the known behavior of vitrinite at high temperatures and, to a lesser extent, at high pressures, it was determined that the duration of the heating, melting, and resolidification event was about 1 h. In the current study, featureless vitrinite within banded maceral assemblages demonstrates the intimate association of melted and resolidified vitrinite with anthracite-rank macerals. By analogy with metamorphosed inorganic rocks, such associations represent diadysites and embrechites, i.e., cross-cutting and layered migmatites, respectively. Even though the temperature of formation of the anthracite structures is several hundred °C lower than that seen in metamorphosed inorganic rocks, anthracites are metamorphic rocks and the nomenclature for metamorphic rocks may be appropriate for coal

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.</p

Emissions during grilling with wood pellets and chips

The quality check of grilling wood pellets should be of a critical importance as smoke from their combustion has a direct contact with food, impacts human safety, and pollutes the atmosphere. Therefore, the main purpose of this study is to investigate the purity of grilling wood pellets and chips available on the market, analyze the properties of their combustion gases, and determine if a relationship between the fuel composition and emissions during grilling can be established. In this study, we investigated 45 types of BBQ wood pellets and wood chips available for purchase in the USA and Europe. Based on reflected light microscopy analysis, the samples are composed dominantly of biomass, ranging from 87.5 to 99.8 vol % for wood pellets and 96.5 to 99.1 vol % for wood chips, with the average impurities content of 1.7 vol % for wood pellets and 2.2 vol % for wood chips. The undesired components included bark, mineral matter, charcoal, coke, metal, rust, slag, and petroleum products. Our data show that grilling with wood pellets and chips leads to elevated emissions of particulate matter (PM), NO2, SO2, CO, CO2, and formaldehyde in comparison with recommended exposure limits. The average emissions of PM are higher from wood chips than from pellets by approximately 85 μg/m3, and they come mainly from PM2.5; the contribution from PM of 2.5–10 μm in size is rather insignificant. CO2 emissions, on average 2.67% from pellets and 2.27% from wood chips, were elevated comparing with a typical outdoor air level of 0.03–0.05% (300–500 ppm). The level of emissions of individual components also changes during the grilling cycle, and depends on the type of combusted wood, grilling conditions and fuel moisture content