A coal-sulfur model for Sydney Coalfield (Upper Carboniferous), Nova Scotia, Canada

Abstract

Methods of modern factor analysis are applied to a set of 31 variables (metals, sulfur and ash) of coal data, with focus on explaining the sulfur variance in coal for the formulation of a coal-sulfur model. The derived five hypo thetical factors which are fitted to the conceptual coal-sulfur model are inferred to represent general sedimentary/ geochemical processes, except for one for which there is no available identity and no corresponding process in the conceptual model. The fluvial sedimentary influx and the pyrite-forming factors are the most influential in explaining the variation of sulfur in the coal, where the latter factors are linked with sulfur supplied from recycled sulfate solution. The factor interpretation is consistent with independent results that identify clay minerals and pyrite as the dominating coal mineralogy in the Sydney Coalfield.

Colliery and surface hazards through coal-pyrite oxidation (Pennsylvanian Sydney Coalfield, Nova Scotia, Canada)

“…This conclusion is based on stable sulfur-isotopic studies of pyrite and gypsum from the Sydney Coalfield (Gibling et al, 1989), and confirms earlier views by Sydney Sub-Basin coalmine geologists from the 1950s (Haites, 1951;summary: Gibling et al, 1989). Low boron content in coals (maximally 50 ppm, Vasey and Zodrow, 1983;Zodrow, 1991), and absence of certain piscine species, confirm the absence of open marine influence. Agglutinated foraminifera, however, found in seat earth of many coals permits interpretation of brackish-estuarine influence in certain parts of the Sydney Coalfield (Thibaudeau, 1987;Wightman et al, 1994).…”

“…Assuming three sources for (1), organic sulfur is calculated by difference. As a generalization for Sydney Coalfield, a total-sulfur level of b 2% in the coals is considered to be of organic origin, following Casagrande (1987), although this has not been verified microscopically, but has been used statistically (Zodrow, 1991). On atmospheric exposure, coals with such small amounts of total sulfur show little or no weathering effects (oxidation), and remain intact over time, whereas those with higher-sulfur [pyrite] content weather and disintegrate rapidly as measured in weeks.…”

“…Estimates that circumscribe the range of total-coal-sulfur content, based on whole-coal channel samples from 10 successive coal seams, Sydney Coalfield, are from b 0.5% to N 22%, average 4.78% F4.31% (Zodrow, 1991). Total-coal sulfur is defined by:…”

Urban Geochemical Hazard Mapping of St. John’s, Newfoundland, Canada

“…Downtown areas of St. John's have soil-Pb levels well above those from Canadian cities of equal or greater population size Beaton et al (1993); and (2) Sydney Coalfield (n = 27) from Zodrow (1991). Metal concentration for select UK coals from Spears and Zheng (1999).…”

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

“…The coals represent lithified autochthonous (or at most hypautochthonous) peat formed by wetland forest-like vegetation, while the intervening clastics were deposited during floods that destroyed the forests. Although there is some evidence of marine influence (Wightman et al, 1994), these floods were essentially nonmarine (Vasey and Zodrow, 1983;Zodrow, 1991) either due to eustatic effects or increased subsidence. Gibling and Bird (1994) interpreted the Sydney Mines Formation in terms of 12 cyclothems with a major coal at the base of each.…”