Geology topics

P.C. Lyons

Publications and source records attributed to P.C. Lyons.

At least 19 recordsLinked to original sources

USGS2009

Organic geochemistry of resins from modern Agathis australis and Eocene resins from New Zealand: Diagenetic and taxonomic implications

A maturation series of resins and fossil resins from New Zealand, ranging in age from Modern to Eocene and ranging from uncoalified to high volatile C bituminous coal, were analyzed by elemental, pyrolysis-gas chromatography (Py-GC), Fourier Transform infrared (FTir), and solid-state 13 C nuclear magnetic resonance ( 13 C NMR) techniques. For comparison, four resin samples from the Latrobe Valley, Australia, were analyzed. All of the resins and fossil resins of this study show very high H/C atomic ratios, and are characterized by dominant peaks in the 10-60??ppm range of solid-state 13 C NMR spectra and prominent bands in the aliphatic stretching region (2800-3000??cm - 1 ) of FTir spectra, all indicating a highly aliphatic molecular structure. The 13 C NMR and FTir data indicate a diterpenoid structure for these resins. There is an abrupt loss of oxygen that occurs at the Lignite A/Subbituminous C stage, which is attributed to a dramatic loss of carboxyl (COOH) from the diterpenoid molecule. This is a new finding in the diagenesis of resins. This important loss in oxygenated functional groups is attributed to a maturation change. Also, there is a progressive loss of exomethylene (CH 2 ) groups with increasing degree of maturation, as shown by both 13 C NMR and FTir data. This change has been noted by previous investigators. Exomethylene is absent in the fossil resins from the Eocene high volatile C bituminous coals. This progressive loss is characteristic of Class I resinites. FTir data indicate that the oxygenated functional groups are strong in all the resin samples except the fossil resin from high volatile C bituminous coal. This important change in oxygenated functional groups is attributed to maturation changes. The 13 C NMR and FTir data indicate there are minor changes in the Agathis australis resin from the living tree and soil, which suggests that alteration of A. australis resins begins shortly after deposition in the soil for as little as 1000??years. The Morwell and Yallourn fossil resins from brown coal (lignite B) Australia do not have some of the FTir characteristics of the New Zealand resins, which most likely indicates they have a different plant source because different degrees of oxidation and weathering and changes due to fires (i.e., charring) can be ruled out. Our results have implications for studies of the maturation, provenance, and botanical sources of fossil resins and resinites in Eocene and Miocene coals and sediments of New Zealand and Australia. ?? 2009 Elsevier B.V. All rights reserved.

International Journal of Coal Geology↗

USGS2006

Radiometric ages of the Fire Clay tonstein [Pennsylvanian (Upper Carboniferous), Westphalian, Duckmantian]: A comparison of U-Pb zircon single-crystal ages and 40Ar/39Ar sanidine single-crystal plateau ages

The Fire Clay tonstein [Pennsylvanian (Upper Carboniferous), Westphalian Series, Duckmantian Stage]-a kaolinized, volcanic-ash deposit occurring in Kentucky, West Virginia, Tennessee, and Virginia-is the most widespread bed in the Middle Pennsylvanian of the central Appalachian basin, USA. A concordant single-crystal U-Pb zircon datum for this tonstein gives a 206Pb/238U age of 314.6 ?? 0.9 Ma (2??). This age is in approximate agreement with a mean sanidine plateau age of 311.5 ?? 1.3 Ma (1??, n = 11) for the Fire Clay tonstein. The difference between the two ages may be due to bias between the 40K and 238U decay constants and other factors. The age of the Fire Clay tonstein has important implications for Duckmantian Stage (Westphalian Series) sedimentation rates, correlations with the Westphalian Series of Europe, Middle Pennsylvanian volcanic events, and the late Paleozoic time scale. ?? 2006 Elsevier B.V. All rights reserved.

International Journal of Coal Geology↗

USGS2001

Secretinite-Reflectance and chemical data from two high volatile bituminous coals (Upper Carboniferous) of North America

Secretinite - a maceral of the inertinite group as recognized by the ICCP in 1996- is a noncellular maceral of seed fern origin. New reflectance data indicate that this maceral has primary anisotropy with bireflectances of 0.4% to 0.9% in high-volatile B bituminous (Ro = 0.6%) Carboniferous coal of North America. The highest reflectance is in cross-section as opposed to longitudinal section. Characteristic feature of secretinite is the virtual absence of Si and Al, unlike that in associated vitrinite. This indicates the absence of submicron aluminosilicates in secretinite and their presence in vitrinites. Secretinite is highly aromatic as indicated by low O/C ratios and high contribution of aromatic hydrogen bands detected by FTIR analysis. ?? 2001 Elsevier Science B.V. All rights reserved.

International Journal of Coal Geology↗

USGS1998

The central and northern Appalachian Basin-a frontier region for coalbed methane development

The Appalachian basin is the world's second largest coalbed-methane (CBM) producing basin. It has nearly 4000 wells with 1996 annual production at 147.8 billion cubic feet (Bcf). Cumulative CBM production is close to 0.9 trillion cubic feet (Tcf). The Black Warrior Basin of Alabama in the southern Appalachian basin (including a very minor amount from the Cahaba coal field) accounts for about 75% of this annual production and about 75% of the wells, and the remainder comes from the central and northern Appalachian basin. The Southwest Virginia coal field accounts for about 95% of the production from the central and northern parts of the Appalachian basin. Production data and trends imply that several of the Appalachian basin states, except for Alabama and Virginia, are in their infancy with respect to CBM development. Total in-place CBM resources in the central and northern Appalachian basin have been variously estimated at 66 to 76 trillion cubic feet (Tcf), of which an estimated 14.55 Tcf (~ 20%) is technically recoverable according to a 1995 U.S. Geological Survey assessment. For comparison in the Black Warrior basin of the 20 Tcf in-place CBM resources, 2.30 Tcf (~ 12%) is technically recoverable. Because close to 0.9 Tcf of CBM has already been produced from the Black Warrior basin and the proved reserves are about 0.8 Tcf for 1996 [Energy Information Administration (EIA), 1997]. U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Reserves, 1996 Annual Report. U.S. Department of Energy DOE/EIA-0216(96), 145 pp.], these data imply that the central and northern Appalachian basin could become increasingly important in the Appalachian basin CBM picture as CBM resources are depleted in the southern Appalachian basin (Black Warrior Basin and Cahaba Coal Field). CBM development in the Appalachian states could decrease the eastern U.S.A.'s dependence on coal for electricity. CBM is expected to provide over the next few decades a virtually untapped source of unconventional fossil fuel in the Appalachian states, where the CBM resources are large and the demand for cleaner fossil-fuel energy is high.The central and northern Appalachian basin could become increasingly important in the Appalachian basin coalbed methane (CBM) picture as CBM resources are depleted in the southern Appalachian basin. Total in-place CBM resources in the central and the northern Appalachian basin have been estimated at 66 to 76 Tcf, of which 14.55 Tcf is technically recoverable.

International Journal of Coal Geology↗

USGS1997

U-Pb age of zircon crystals from the upper banner tonstein (Middle Pennsylvanian), Virginia: Absolute age of the Lower Pennsylvanian-Middle Pennsylvanian boundary and depositional rates for the Middle Pennsylvanian, central appalachian basin

The Upper Banner tonstein, a kaolinized volcanic ash bed that occurs about 90 m above the base of the Middle Pennsylvanian Series in Virginia, is the oldest known Middle Pennsylvanian tonstein in the Appalachian basin. On the basis of palynostratigraphy, the Upper Banner coal bed correlates approximately with the Langsettian-Duckmantian (ex Westphalian A-B) boundary in Europe. Stratigraphically, the Upper Banner tonstein occurs 440-480 m below the Fire Clay tonstein, which in turn is 25-50 m below the marine Magoffin Member of the Breathitt Formation, the approximate correlative of the Agir Marine Band that marks the Dunckmantian-Bolsovian (ex Westphalian C) boundary in Europe. Six single-crystal U-Pb zircon ages were determined for the Upper Banner tonstein. Of these, four overlap concordia within uncertainties and have 206Pb/238U ages that range from 306 to 310??1 Ma. Another analysis falls in the same group but plots slightly to the right of the curve, whereas a single analysis of a low uranium zircon grain gives an age of 316??1 Ma. Variation in ages is outside of analytical uncertainty; hence, variable amounts of recent Pb loss is implied, and the most probable (minimum) depositional age is given by the oldest value at 316??1 Ma - an age consistent with a mean sanidine 40Ar/39Ar plateau age of 311.2??0.7 Ma for the stratigraphically younger Fire Clay tonstein. Thus, the Upper Banner tonstein-Fire Clay tonstein interval is about 5 ?? 1 m.y. This period of time for the Dunckmantian Stage is in good agreement with the Hess and Lippolt (1986) and Hess et al. (1988) chronology for the Duckmantian based on 40Ar/39Ar plateau methods for Westphalian tonsteins. Also, on the basis of this period of time, calculated sedimentation rates (decompacted) od 66-165 m/m.y. were determined for the lower part of the Middle Pennsylvanian Series in the central Appalachian basin. These rates are consistent with the sedimentation rates for shallow-water marine siliciclastic sediments and passive-margin foreland sediments.

Prace - Panstwowego Instytutu Geologicznego↗

USGS1996

Geochemistry of autochthonous and hypautochthonous siderite-dolomite coal-balls (Foord Seam, Bolsovian, Upper Carboniferous), Nova Scotia, Canada

The 11–13 m thick Foord Seam in the fault-bounded Stellarton Basin, Nova Scotia, is the thickest seam from the Euramerican floral province known to contain coal-balls. In addition to the first discovery of autochthonous coal-balls in the Foord Seam, Nova Scotia, its shale parting also contains hypautochthonous coal-balls with histologically preserved plant structures. The coal-ball discovery helps fill a stratigraphic gap in coal-ball occurrences in the upper Carboniferous (Bolsovian) of Euramerica. The autochthonous and hypautochthonous coal-balls have a similar mineralogical composition and are composed of siderite (81–100%), dolomite-ankerite (0–19%), minor quartz and illite, and trace amounts of `calcite'. Similar is also their permineralizing mineralogy, which consists of dolomite-ankerite and siderite. Their low pyrite content and carbonate mineralogy, and nonmarine origin, differentiates the Foord Seam coal-balls from other Euramerican coal-ball occurrences. A preliminary geochemical model, which is based on oxygen and carbon isotopic data, indicates that siderite in both the autochthonous and hypautochthonous coal-balls is of very early diagenetic (nonmarine) origin from 13 C-enriched bicarbonate derived from bacterial methanogenesis of organic matter.

International Journal of Coal Geology↗

USGS1996

Selected elements in major minerals from bituminous coal as determined by INAA: Implications for removing environmentally sensitive elements from coal

The four most abundant minerals generally found in Euramerican bituminous coals are quartz, kaolinite, illite and pyrite. These four minerals were isolated by density separation and handpicking from bituminous coal samples collected in the Ruhr Basin, Germany and the Appalachian basin, U.S.A. Trace-element concentrations of relatively pure (??? 99+%) separates of major minerals from these coals were determined directly by using instrumental neutron activation analysis (INAA). As expected, quartz contributes little to the trace-element mass balance. Illite generally has higher trace-element concentrations than kaolinite, but, for the concentrates analyzed in this study, Hf, Ta, W, Th and U are in lower concentrations in illite than in kaolinite. Pyrite has higher concentrations of chalcophile elements (e.g., As and Se) and is considerably lower in lithophile elements as compared to kaolinite and illite. Our study provides a direct and sensitive method of determining trace-element relationships with minerals in coal. Mass-balance calculations suggest that the trace-element content of coal can be explained mainly by three major minerals: pyrite, kaolinite and illite. This conclusion indicates that the size and textural relationships of these major coal minerals may be a more important consideration as to whether coal cleaning can effectively remove the most environmentally sensitive trace elements in coal than what trace minerals are present.

International Journal of Coal Geology↗

USGS1994

Euramerican tonsteins: Overview, magmatic origin, and depositional-tectonic implications

Carboniferous tonsteins (kaolinized volcanic-ash beds) of wide geographic distribution are known in both Europe and North America. Relict volcanic minerals common in these Euramerican tonsteins are volcanic quartz (including beta-quartz paramorphs), zircon and ilmenite; less common are magnetite, fayalite, rutile, monazite, xenotime, apatite and sanidine. Data for two relatively thick (3-13 cm) and widespread (>400 km) European tonsteins (Erda and Sub-Worsley Four-foot) indicate an increase in detrital quartz near the top of the beds which indicates mixing with normal clastic sediments, including the introduction of heavy detrital minerals (e.g., tourmaline and garnet). These thick tonsteins show multiple horizontal bedding, normal graded bedding, disturbed bedding, and centimeter-scale scour surfaces. The Fire Clay tonstein in North America represents from one to five separate volcanic air-fall ash deposits as determined by normal graded bedding and mineralogical analysis. These features indicate several episodes of volcanic-ash deposition and very localized subsequent erosion and bioturbation. Electron microprobe data from glass inclusions in volcanic quartz in Euramerican tonsteins indicate a rhyolitic origin for these tonsteins and reveal chemical "fingerprints" valuable for intra- and inter-basinal correlations. However, the tectonic framework for European and North American tonsteins was quite different. In Europe, volcanic-ash beds were associated with Variscan collisional tectonics, whereas in North America, volcanic ash was associated with Ouachita tectonic activity, explosive volcanism from the Yucatan block, collision between the South American and North American plates, and the formation of Pangea.

Palaeogeography, Palaeoclimatology, Palaeoecology↗

USGS1992

An Appalachian isochron: A kaolinized Carboniferous air-fall volcanic-ash deposit (tonstein)

The Fire Clay tonstein is a kaolinized, airfall volcanic ash bed that was deposited in a widespread late Carboniferous peat-forming mire. Eleven samples from Kentucky and West Virginia, spanning a distance of 200 km, and two samples from Tennessee and Virginia indicate a characteristic mineralogical signature, as compared with other Appalachian tonsteins, consisting of well-crystallized kaolinite, beta-quartz crystal paramorphs, sanidine, ilmenite, zircon, and brookite. Detrital illite and quartz are rarely present or are in very small amounts, which indicates rapid deposition in a mire. Several normal graded cycles in this tonstein suggest repeated episodes of pyroclastic activity that produced a composite ash layer. A high-silica alkalic rhyolitic source is suggested by the geochemistry of immobile elements and by electron-probe analyses of glass inclusions in volcanic quartz from the Fire Clay tonstein. The rare-earth-element plots (chondrite normalized) of the tonstein show a pronounced negative Eu anomaly and relatively high concentrations of Zr and Th, which are both indicative of a rhyolitic source. Probe analyses of the Fire Clay glass inclusions from four states indicate a chemically identical high-silica rhyolite with peraluminous affinities. 40 Ar/ 39 Ar sanidine plateau dating indicates an age of 312 ± 1 Ma for the Fire Clay tonstein, which is consistent with previous 40 Ar/ 39 Ar dates for this tonstein. This age is in agreement with a late Westphalian B age in the European Carboniferous chronostratigraphy on the basis of an age of 311 Ma for the Westphalian B/C boundary. A new isopachous map of the Fire Clay ash-fall deposit indicates an area of 37,000 km 2 and a probable source to the present-day southwest. The deposit has a minimum preserved compacted volume of 2.8 km 3 , which corresponds to an original uncompacted volume of about 20 km 3 . This preserved volume indicates an ultraplinian volcanic explosion. Pindell and Dewey (1982) proposed an Andean-type arc in this block during the late Carboniferous, prior to South American-North American plate collision. We hypothesize an associated back-arc caldera system in the Yucatan block to explain the high-silica, potassic rhyolitic ash that gave rise to the Fire Clay tonstein.

Geological Society of America Bulletin↗

USGS1991

Bacteria-like bodies in coalified Carboniferous xylem-enigmatic microspheroids or possible evidence of microbial saprophytes in a vitrinite precursor?

Possible fossil cocci, both solitary and diplococcus types, have been discovered in coalified tissue (xylem) from coal balls and bituminous coal of Carboniferous age. Most of the presumed bacteria are microspheroids 1–2.5 μm in diameter and were found in partly degraded humic tissue (xylem) from a medullosan seed fern preserved in a coal ball (Herrin No. 6 coal bed, Westphalian D), an indication that they may have been saprotrophs (decay causing). The same kind of bodies were also found in coalified xylem from the Pittsburgh coal bed (early Stephanian). Whatever the origin of the bacteria-like bodies, they provide direct evidence of secondary organic components in tissue that gives rise to vitrinite and fusinite, major macerals of bituminous and anthracitic coals.

International Journal of Coal Geology↗

USGS1990

The laser microprobe mass analyser for determining partitioning of minor and trace elements among intimately associated macerals: An example from the Swallow Wood coal bed, Yorkshire, UK

A study of the elemental composition of intimately associated coal macerals in the English Swallow Wood coal bed was conducted using a laser microprobe mass analyser, and indicated a similar trace and minor elemental chemistry in the vitrinite and cutinite and a different elemental signature in the fusinite. Three to six sites were analysed within each maceral during the study by laser micro mass spectrometry (LAMMS). Al, Ba, Ca, Cl, Cr, Dy, F, Fe, Ga, K, Li, Mg, Na, S, Si, Sr, Ti, V, and Y were detected by LAMMS in all three macerals but not necessarily at each site analysed. The signal intensities of major isotopic peaks were normalized to the signal intensity of the m z "> mz 85 peak (C 7 H) to determine the relative minor- and trace-element concentrations among the three dominant macerals. The vitrinite and the cutinite were depleted in Ba, Ca, Dy, Li, Mg, Sr, and Y relative to their concentrations observed in the fusinite. The cutinite was distinguished over vitrinite by less Ti, V, Cr and Ca, and K Ca $ ̆ 1 "> KCa$1 (relative signal intensities). The fusinite, relative to the cutinite and vitrinite, was relatively depleted in Cr, Sc, Ti, and V. The fusinite, as compared with both the cutinite and vitrinite, was relatively enriched in Ba, Ca, Dy, Li, Mg, Sr, and Y, and also showed the most intense m z "> mz 64, 65, 66 signals (possibly S 2 + , HS 2 + , H 2 S 2 + , respectively). The LAMMS data indicate a common source for most elements and selective loss from the maceral precursors in the peat or entrapment of certain elements as mineral matter, most likely during the peat stage or during early diagenesis. The relatively high amounts of Ba, Ca, Dy, Li, Mg, Sr, and Y in the fusinite are consistent with micron and submicron mineral-matter inclusions such as carbonates and Ca-Al phosphates (probably crandallite group minerals). Mineralogical data on the whole coal, the LAMMS chemistry of the vitrinite and cutinite, and scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDAX) of the elements in the macerals are consistent with the presence of micron and submicron inclusions of clays such as kaolinite, illite, and Ca-rich or Ca-bearing minerals (e.g. calcite, Ca-Al phosphates, and illite) which are different in kind and proportions in the three macerals. The variance as measured by the F -statistic for all three macerals indicates generally a nonuniform distribution of minor and trace elements in all three macerals, thus supporting a mineral-matter (inorganic) origin of the elements analysed. Exceptions are Al, K, Fe, Ga, and Sr in the vitrinite and cutinite, which is consistent with organic complexing or a uniform distribution of micron or submicron mineral matter such as illite and phosphate(s).

Yorkshire↗

USGS1990

Thrust-ridge paleodepositional model for the Upper Freeport coal bed and associated clastic facies, Upper Potomac coal field, Appalachian Basin, U.S.A.

A blind-thrust-ridge model is proposed to explain the lack of coarse clastic material in the vast minable Upper Freeport coal bed (UF). This coal bed contains only fine elastic partings and is overlain by regionally extensive, closely spaced channel-belt deposits in the Upper Potomac coal field of the Appalachian basin. A blind-thrust ridge may have formed a sediment trap and prevented c coarse fluvial sediments from entering the swamp during a period (Westphalian D) when the thick Upper Freeport peat accumulated. Anticlinal thrust ridges and associated depressions may have existed uninterrupted for about 40 km parallel to the Appalachian orogen. Sediment shed from the breached anticlinal ridges accumulated in the sediment trap and was carried out of the ends of the trap by streams that occupied the shear zone at the ends of the blind-thrust ridge. The extent, parallel to the orogen, of thick, areally extensive UF is related to the length of the blind-thrust ridge that, in turn, controlled the spacing of the river-derived coarse clastic sediments that entered the main basin from the east. The thrust plane eventually emerged to the surface of the blind-thrust ridge and peat accumulation was terminated when the ridge became eroded and the sediment trapped behind it was released. The peat was buried by abundant coarse clastic sediment, which formed closely spaced channel belts and intervening flood basins. This model has implications for widespread peat deposits (now coal) that developed in tropical regions a few hundred kilometers from the sea in a tectonically active foreland basin.

International Journal of Coal Geology↗

USGS1990

Chemistry and origin of minor and trace elements in selected vitrinite concentrates from bituminous and anthracitic coals

Organic and inorganic affinities were determined by comparing the elemental concentrations in the vitrinite concentrates to the concentrations in the companion whole coals. The ratios of these concentrations for 33 selected elements are shown in Figure 1. Ratios greater than 1 indicate organic affinity, and ratios less than 1 indicate inorganic affinity. Br and W generally showed organic affinity in all samples in this study. In the nine samples from the eastern United States (Fig. 1A-C) less than one-fourth of the trace elements show organic affinity compared to nearly one-half for the three English and Australian samples (Fig. 1D). The elements that generally show organic affinity in the non-U.S.A. samples studied include As, Cs, Hf, and Ni, which have generally inorganic affinities in the U.S.A. samples, and Cr, Sb, Se, and U, which have mixed (both organic and inorganic) affinities, in the U.S.A. coals studied, has an inorganic affinity in the English coals studied. B shows organic affinity in the samples from the Illinois basin (Fig. 1C). For the samples studied, Ba shows organic affinity in the Appalachian basin bituminous coals (Fig. 1B), inorganic affinity in the Illinois basin coals, and overall mixed affinities. In all the samples studied, Cu, Mn, Na, Sr, Ta, V, and Zn show mixed affinities, and A1, Co, Eu, Fe, Ga, K, La, Mg, Sc, Si, Th, Ti, and Ub have generally inorganic affinity.

International Journal of Coal Geology↗

USGS1989

Marine origin of pyritic sulfur in the Lower Bakerstown coal bed, Castleman coal field, Maryland (U.S.A.)

The amount, kind, distribution, and genesis of pyrite in the Lower Bakerstown coal bed in a 150 × 15 m area of the Bettinger mine, Castleman coal field, Maryland, were studied by various analytical techniques. The mined coal, which had a nonmarine roof rock, contained 1.4–2.8 wt.% total sulfur, generally much lower than the high-sulfur coal (> 3.0 wt.% total S) to the north, which is associated with marine roof rocks. Small-scale systematic and nonsystematic variations in total sulfur and pyrite distribution were found in the mined area. In the column sample, most of the pyrite was found in the upper 9 cm of the 69-cm-thick mined coal and occurred mainly as a pyrite lens containing cell fillings in seed-fern tissue (coal ball). As-bearing pyrite was detected by laser microprobe techniques in the cell walls of this tissue but not elsewhere in the column sample. This may indicate that the As was derived from decomposition of organic matter in the cell walls. The sulfur isotopic composition and distribution of pyrite in the coal are consistent with introduction of marine sulfate shortly after peat deposition, followed by bacterial reduction and pyrite precipitation. Epigenetic cleat pyrite in the coal is isotopically heavy, implying that later aqueous sulfate was 34 S-enriched.

International Journal of Coal Geology↗

USGS1989

Chemistry and origin of minor and trace elements in vitrinite concentrates from a rank series from the eastern United States, England, and Australia

A rank series consisting of twelve vitrinite concentrates and companion whole-coal samples from mined coal beds in the eastern United States, England, and Australia were analyzed for C, H, N, O, ash, and 47 trace and minor elements by standard elemental, instrumental neutron activation analysis (INAA), and direct-current-arc spectrographic (DCAS) techniques. The reflectance of vitrinite, atomic H:C and O:C, and ash-free carbon data were used to determine ranks that range from high-volatile C bituminous coal to meta-anthracite. A van Krevelen (atomic H:C vs. O:C) diagram of the vitrinite concentrates shows a smooth curve having its lowest point at H:C = 0.18 and O:C = 0.01. This improves the van Krevelen diagram by the addition of our vitrinite concentrate from meta-anthracite from the Narragansett basin of New England. Boron content (400–450 ppm) in two Illinois basin vitrinite concentrates was about an order of magnitude higher than B contents in other concentrates analyzed. We attribute this to marine origin or hydrothermal activity. The alkaline-earth elements Ca, Mg and Ba (DCAS) have higher concentrations in our vitrinite concentrates from bituminous coals of the Appalachian basin, than they do in vitrinite concentrates from the marine-roofed bituminous coals of the Illinois basin; therefore, a nonmarine origin for these alkaline-earth elements is postulated for the Appalachian basin coals. An ion-exchange mechanism due to high concentrations of these elements as ions in diagenetic water, but probably not recent ground water, may be responsible for the relatively high values of these elements in Appalachian concentrates. Higher concentrations of Ni and Cr in one of the English vitrinite concentrates and of Zr in the Australian concentrate probably indicate organic association and detrital influence, respectively.

International Journal of Coal Geology↗

USGS1988

Using laser micro mass spectrometry with the LAMMA-1000 instrument for monitoring relative elemental concentrations in vitrinite

The variation in relative elemental concentrations among a series of coal macerals belonging to the vitrinite maceral group was determined using laser micro mass spectrometry (LAMMS). Variations in Ba, Cr, Ga, Sr, Ti, and V concentrations among the coals were determined using the LAMM A-1000 instrument. LAMMS analysis is not limited to these elements; their selection illustrates the application of the technique. Ba, Cr, Ga, Sr, Ti, and V have minimal site-to-site variance in the vitrinite macerals of the studied coals as measured by LAMMS. The LAMMS data were compared with bulk elemental data obtained by instrumental neutron activation analysis (INAA) and D. C. arc optical emission spectroscopy (DCAS) in order to determine the reliability of the LAMMS data. The complex nature of the ionization phenomena in LAMMS and the lack of standards characterized on a microscale makes obtaining quantitative elemental data within the ionization microvolume difficult; however, we demonstrate that the relative variation of an element among vitrinites from different coal beds in the eastern United States can be observed using LAMMS in a "bulk" mode by accumulating signal intensities over several microareas of each vitrinite. Our studies indicate gross changes (greater than a factor of 2 to 5 depending on the element) can be monitored when the elemental concentration is significantly above the detection limit. "Bulk" mode analysis was conducted to evaluate the accuracy of future elemental LAMMS microanalyses. The primary advantage of LAMMS is the inherent spatial resolution, ~ 20 ??m for coal. Two different vitrite bands in the Lower Bakerstown coal bed (CLB-1) were analyzed. The analysis did not establish any certain concentration differences in Ba, Cr, Ga, Sr, Ti, and V between the two bands. ?? 1988 Springer-Verlag.

Mikrochimica Acta↗

USGS1987

Application of laser microprobe (LAMMA 1000) to "fingerprinting" of coal constituents in bituminous coal

A laser microprobe (LAMMA-1000) microchemical analysis of vitrinites of different morphologies but similar reflectances within the same bituminous coal bed indicates distinct “fingerprint” spectra. The banded form of vitrinite contains Li, Ti, Ba, Sr, F, and Cl which were not detected in the nonbanded vitrinite. These differences may indicate a different plant source or the introduction of these elements from fluids mobilized during diagenesis. The nonbanded vitrinite (called corpocollinite), which was contained in a pyrite coal-ball seed fern permineralization of Myeloxylon , may have been protected from influx of these elements due to entrapment by pyrite during an early peat stage. An ion at M/Z 65, which is characteristic of the banded vitrinite, may indicate C 5 H 5 + and, perhaps a difference in the chemical structure of the two vitrinites. These results demonstrate that “fingerprint” spectra can be obtained from vitrinite macerals by LAMMA and that these “fingerprints” have genetic implications.

International Journal of Coal Geology↗

USGS1986

Secretinite: A proposed new maceral of the inertinite maceral group

The new maceral secritinite (name derived from the word ‘secretory’) is proposed for subcircular, ovoid, crescent-shaped or oblong, commonly round on one or more sides, noncellular, highly reflective components of the inertinite maceral group. This maceral of secretory origin, known from many bituminous coals throughout the world, has been confused with cellular, opaque fungal masses of high reflectance. It is suggested that these fungal masses be assigned to the previously proposed maceral funginite of the inertinite maceral group. The maceral term ‘sclerotinite’ and maceral-varietal terms ‘fungo-sclerotinite’ and ‘resinosclerotinite’ should be abandoned because they confuse the natural botanical relations and because they are unnecessary if the proposed maceral names, secretinite and funginite, are accepted. The maceral-varietal terms secreto-macrinite and secreto-inertodetrinite are proposed for angular to irregular constituents whose properties are physically gradational from secretinite into the macerals macrinite and inertodetrinite.

Fuel↗