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F. W. Brown

Publications and source records attributed to F. W. Brown.

11 recordsLinked to original sources
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↗
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↗
USGS1985

ROLE OF STATIC LOAD (OVERBURDEN) PRESSURE IN COALIFICATION OF BITUMINOUS AND ANTHRACITIC COAL.

Tissue from a calcite concretion (coal ball) and attached coal of semianthracite rank from the Belgium Bouxharmont coal bed were analyzed separately by elemental chemical, **1**3C nuclear magnetic resonance, reflectance, and paleobotanical techniques to compare relative degrees of coalification. The results indicate that static load pressure has no perceptible effect on coalification up to and including a rank of semianthracite.

Conference Paper↗
USGS1984

Coalification of organic matter in coal balls of the Pennsylvanian (upper Carboniferous) of the Illinois Basin, United States

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.

Illinois, Indiana, Kentucky↗
USGS1984

The Georges Bank monitoring program 1983: Analysis of trace metals in bottom sediments

From July 1981, when drilling began on Georges Bank, to May 1982, the concentration of barium, a major element in drilling mud, has increased by a factor of 3.5 in bulk sediments 200 m from the drill site in block 410 and by a factor of 2.3 at the drill site in block 312. The postdrilling barium concentrations are within the range of predriiling concentrations measured at other locations on Georges Bank. We estimate that no more than 21 percent of the barite (principal barium-bearing mineral) discharged during drilling remains within 6 km of the drill site in block 312. No drilling-related changes in the concentration of chromium or other metals have been observed in bulk sediments from blocks 410 or 312. The chemical signal of drilling mud in surficial sediments has been enhanced by separating and analyzing the sediment fraction finer than 60 ?m. Barium concentrations in the fine fraction have increased by factors of 36 and 22 at the drill sites in blocks 410 and 312, respectively. At the drill site in block 410, aluminum, chromium, copper, and mercury concentrations in this fraction temporarily increased by approximately a factor of 2 and then decreased to background. The concentrations of aluminum, barium, cadmium, chromium, copper, iron, lead, manganese, mercury, nickel, organic carbon, vanadium, and zinc in surface sediments of Georges Bank both before and after drilling are low compared to concentrations in average crustal rocks and are characteristic of unpolluted, coarse-grained sediments as found in other Continental Shelf areas.

Georges Bank↗
USGS1982

Properties, origin and nomenclature of rodlets of the inertinite maceral group in coals of the central Appalachian basin, U.S.A.

Resin rodlets, sclerenchyma strands and woody splinters, which are collectively called rodlets, were studied by chemical, optical petrographic, and scanning-electron microscopic (SEM) techniques. A study was made of such rodlets from the bituminous coal beds of the central Appalachian basin (Pennsylvanian; Upper Carboniferous) of the United States. Comparisons were made with rodlets from coal beds of the Illinois basin, the Southern Anthracite Field of Pennsylvania, the St. Rose coal field of Nova Scotia, and European and other coal fields. In order to determine their physical and chemical properties, a detailed study was made of the rodlets from the Pomeroy coal bed (high volatile A bituminous coal; Monongahela Formation; Upper Pennsylvanian) of Kanawha County, West Virginia. The origin of the rodlets was determined by a comparative analysis of a medullosan (seed fern) stem from the Herrin (No. 6) coal bed (high volatile C bituminous coal; Carbondale Formation) from Washington County, Illinois. Rodlets are commonly concentrated in fusain or carbominerite layers or lenses in bituminous coal beds of the central Appalachian basin. Most of the rodlets examined in our study were probably derived from medullosan seed ferns. The three types of rodlets are distinguished on the basis of cellularity, morphology and fracture.

International Journal of Coal Geology↗
USGS1982

Organic matter in a coal ball: Peat or coal?

Chemical analyses of morphologically preserved organic matter in a Carboniferous coal ball reveal that the material is coalified to a rank approximately equal to that of the surrounding coal. Hence, the plant tissues in the coal ball were chemically altered by coalification processes and were not preserved as peat.

Science↗
USGS1975

Spectrophotometric-isotope dilution determination of arsenic in soils and rock

Arsenic in soil and rock samples may be determined in part-per-million concentrations using a radiochemical-isotope dilution method. Arsenic in the sample plus added As 76 tracer is separated as arsine and determined spectrophotometrically as a molybdenum blue complex. The As 76 activity in the absorbing solution allows corrections for chemical losses. A lower limit of 1 ppm is determinate in a 0.5-g sample.

Journal of Research of the U.S. Geological Survey↗