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Seventeen coal and carbonaceous shale samples taken from eight stratigraphic sections of the Devonian Hecla Bay and Weatherall formations in Arctic Canada, were examined using reflected light microscopy, instrumental neutron activation analysis (INAA), and inductively coupled plasma emission spectroscopy (ICPES). Samples consist of humic coal with 62–79 vol% vitrinite, liptinite-rich humic coal with 42 vol% liptinite, and cannel coal with 52–81 vol% sporinite content. Carbonaceous shale has 46–73 vol% mineral matter and canneloid shale has 30–42 vol% mineral matter as well as 22–38 vol% sporinite content. Most were deposited in areas characterized by minor channel cut-and-abandonment and lake and bay infills peripheral to distributary complexes. A fresh water environment is indicated by Boron (18–71 ppm), low inertinite (0–7.8 wt%), and high sporinite content (30–81 vol%). The ratio of Na/K versus liptinite content shows that coals and associated sediments from the Hecla Bay Formation experienced a more rapid rate of sedimentation than the carbonaceous shales from the Weatherall Formation. The highest total REEs and LREE (La-Gd) was in the liptinite-rich humic coal, followed by humic coal and carbonaceous shale. The concentration of REEs and LREEs in the cannel coals is half of that measured in the liptinite-rich humic coal. The PAAS normalized for oil shales follows two different patterns: 1) the liptinite-rich coal samples display a sharp increase from Nd to Ho, then maintain a similar pattern up to Lu; and 2) samples of other lithologies increase from Nd to Dy, and then maintain a flat trend up to Lu. Hierarchical cluster analysis shows that canneloid and liptinite-rich coal exhibit the greatest similarity with each other whereas humic coal and liptinite-rich coal show the greatest dissimilarity with carbonaceous shale.

The concentration of boron in Australian and Canadian coals determined using atomic emission spectrometry (AES), inductively coupled plasma spectrometry (ICP-AES) and prompt gamma-ray spectrometry is summarized in order to assess the variation of B content in coal with respect to rank, age, geological setting (in-seam and stratigraphic) and the degree of paleosalinity of the coal-forming environment. This study indicates that no/or very complex relations exist between boron and rank (subbituminous to anthracite). Variations of B with ash content for Canadian coals of different age (Devonian to Oligocene-Eocene) indicate that the B content of coals is not governed by the age of the coal. There is some evidence of variation of B with maceral content in Canadian coals, particularly as related to the inertinite and vitrinite content of coals. The B content of coal seams is sensitive to the environment of deposition, with B contents remaining relatively stable and within the range of values designated for each depositional setting. However, B values may show variation in the same seam laterally due to changes of the environment of deposition and/or the enrichment of B by a secondary source. The vertical variation of B in a coal-bearing section or strata is related to depositional environment and lithology of rock. There is often little variation in B content for coal layers as compared to the partings (dirt bands). The B content of partings in a coal-bearing strata may vary greatly as compared to the coal seams. After reappraising earlier work, and on the basis of more recent studies on Australian and Canadian coals, it is proposed that the following ranges of values for B in coal indicate the degree of marine influence during the early stages of coalification: • up to 50 ppm B: freshwater-influenced coals • 50–110 ppm B: mildly brackish water-influenced coals • >110 ppm B: brackish water-influenced coals. Using these criteria, assessments are given for the degree of marine influence on Canadian and Australian coals.

Rank, maceral composition and elemental concentrations of coals, volcanoclastics and sedimentary partings from coal-bearing strata in the Blakeburn opencast mine, British Columbia, are determined using reflected light microscopy, INAA and inductively coupled plasma emission spectrometry (boron only). Petrologically, the coal is similar to that from the Hat Creek coal deposits Nos. 1 and 2 of British Columbia, with vitrinite the dominant maceral group and inertinite macerals contributing only a small percentage. Three depositional cycles are observed; each representing a particular sedimentological and petrological environment of deposition. The coal in Cycles I and II was deposited in a freshwater environment with an almost uniform rate of subsidence; the coal in Cycle III also formed in a freshwater environment but was subject to erratic subsidence rates. Distribution of certain elements is similar to that of the Hat Creek coals (e.g., Al, Br, Cr, Ca, Mo, Se, Ti, W), indicating a certain degree of regional lateral persistence of elemental distribution. Vertical variations of elemental concentrations are primarily related to the lithology. Organically-bound elements are concentrated mainly in coal, and inorganically bound elements are found in the volcanoclastic and sedimentary partings.

Elemental compositions of coals from Fording, southeastern British Columbia, were examined using INAA and ICP spectrometry. Detailed elemental analyses were carried out for coal seams in two equivalent sections and also within selected coal seams. Elemental concentrations in coal bands within individual seams were compared with those of tonstein bands and other partings within coal seams. There was an overall decrease in the concentration of Al, As, Lu, Sc and Th for coal bands within a coal seam. In contrast, the concentration of these elements in partings in the same seam remained almost constant or increased from roof to floor. Concentrations of certain elements, for example K, Mg, Mn, Na, Sb, Th, U, V and Zn for coal samples occurring in the Eagle Mountain section, follow similar trends. Regular variation in the concentration or depletion of some elements indicates the presence of three cycles at Eagle Mountain and two cycles in the Greenhills section. A good correlation was observed between B concentration and the environment of deposition of these coals; particularly when the B contents of coals deposited in fresh water and a brackish environment are compared. The coals in the Eagle Mountain section were deposited in a semi-brackish environment, with the exception of the four uppermost coal samples which were deposited in a freshwater to semi-brackish environment. Correlations between B and S, or B and the Br/Cl ratio were clearly grouped, according to the depositional environment of the coals. Concentration of Cr was greater for coals deposited in fresh water; in contrast the Th was more abundant in brackish coals.

The concentration of 52 elements in a suite of fresh coal seams and their weathered outcrops was determined using INAA. The concentration of organically bound elements such as Br, Cl and S in samples from weathered outcrops was lower than their fresh samples. In contrast, the concentration of inorganically bound elements, such as Al, Ga and Fe, in fresh samples was lower than their weathered outcrops. The concentration or depletion of elements with intermediate bonding such as S in weathered samples, was dependent on its affinity towards the organic or inorganic fraction of coal.