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Photoacoustic infrared spectroscopy has been used to examine the chemical structures of resinites collected from coals of western Canada, Arctic Canada and Australia. Variations in the chemical structure of the resinites were examined from the point of view of location of the resinite within the coal-bearing strata and coal-bearing section and the effect of rank and age. The effects of weathering were analyzed in terms of the structures determined by infrared spectroscopy of the more weathered exterior surface as compared to the less weathered, unexposed interior surface. The molecular structure of the less weathered interior surfaces was found to be rather similar for resinites of similar rank. The exterior weathered surfaces were usually quite different and these differences were related to rank and the degree of weathering influenced by the depositional environment.

The coal petrology, mineralogy, and elemental composition was determined on the 5-m-thick lignite of the Estevan seam, Bienfait Mine, southwest Saskatchewan. Organic petrology reveals a dominance of huminite macerals (73%), with minor liptinite (7%) and inertinite (11%) macerals. The maceral assemblage, and the banded nature of the coal suggests a forest moor depositional environment for the lignite. Optical and scanning electron microscopy, and X-ray diffraction reveals that the dominant mineralogy of the coal is quartz and carbonates with minor sulfates. The roof, parting and floor rock are dominated by quartz and clays, with minor feldspars. Elemental concentration is rather uniform with depth. Most elements are associated with the mineral matter, and increase with increasing ash content. The elements B, Na, Sr and Br are associated with the organic portion of the coal. Some elements show both a mineral and organic association (As, Ba, Co, Fe, Mo, Ce, Dy, Lu, W, U). The high concentrations of certain elements (Na, B, Ca) is attributed to groundwater circulation which can both introduce and remove elements from the porous lignite.

Some of the oldest coals in the world are found within the Middle to Upper Devonian clastic wedge of the Canadian Arctic Archipelago. The coals investigated here occur in the Weatherall, Hecla Bay and Beverly Inlet formations on western Melville Island and range in age from Late Givetian to Middle Frasnian. Many of these coals are rich in liptinite macerals, particularly sporinite and hence can be termed canned coals. Both elemental and Rock-Eval analysis indicate these coals have the potential to generate liquid hydrocarbons. A good correlation between % liptinite with both H/C or Hydrogen Index is observed up to about 50% liptinite after which the latter two parameters level off. The coals range in maturity from 0.61 to 0.87% R o and hence should be in the oil window. The amounts of hydrocarbons that can be extracted from the coals when expressed in mg/g organic carbon are very low, suggesting that they are poor source rocks for oil. All the extracts except for the most mature and vitrinite-rich sample show high pr/ph ratios and biomodal n -alkane distributions. A cannel coal from The Beverley Inlet Formation has a very unusual triterpane distribution that includes regular, AB-ring desmethyl and AB-ring methyl hopanes. Steranes are in very low concentrations compared to hopanes in all samples. The relative abundance of C 28 and C 29 steranes appears to be influenced by maceral composition. Hydrous pyrolysis at 330°C for 72 h generated greater amounts of hydrocarbons from the coals suggesting they could be the source of liquid hydrocarbons at greater maturities. The hydrous pyrolysis experiments also indicate that thin-walled spores are more reactive than thick-walled spores at lower temperatures. The coals on Melville Island are not thought to be significant source rocks for the oil and gas occurrences in this area of the Canadian Arctic because they make up only a very small fraction of the total sedimentary package.

International audience; The Mannville coals in the Fenn area, Alberta Plains, have desorbed gas content averaging 8.57 cm3/g (275 scf/t), which is similar to the same coals in the Corbett Creek area, almost 400 km away. Vitrinite reflectance values are also similar, although the coals at Corbett Creek are situated about 300 m shallower, which points to a rank excursion from Hilt's burial law curves at Corbett Creek. Coals from both areas are within the “oil window”. The Medicine River Seam in the Fenn area has higher total inertinite content and greater proportions of inertodetrinite and detrovitrinite, suggesting that peat deposition occurred in swamps and marshes and were prone to periodic flooding. At Corbett Creek, the Mannville coal seams are characterized by greater concentrations of telo-inertinite, which contributes to coal meso-porosity and the potential for free gas storage in the open cell lumens, and to an increased gas flow along lithotype boundaries (horizontal permeability). Non-fluorescing vitrinite was present mostly in the upper Medicine River Seam, which was deposited in a regressive environment. The lower Medicine River Seam, which formed during a marine transgressive phase, contained greater amounts of fluorescing vitrinite. The Mannville coals in the Fenn area are moderately under-pressured in relation to those at Corbett Creek, which may have an impact on gas retention capacity. The difference in absolute coal permeability (1-3.5 mD at Fenn versus 3-4 mD at Corbett Creek), which is likely the result of higher in-situ stresses in the deeper Mannville coals at Fenn, has had an effect on both gas and water production rates from these coals. However, the largest impact on gas production volumes has been made by the application of horizontal drilling technology, initially at Fenn, and more recently by multiple horizontal wells drilled at Corbett Creek.

The Obed-Marsh coal deposit is of Late Paleocene age, and contains over 200 million tons of subbituminous-B to high-volatile bituminous-C coal. Petrographic analysis of three sections from seams 1 and 2 reveals high amounts of huminite and relatively low amounts of liptinite and inertinite, with the exception of some intervals in both seems. The persistent high ratio of huminite to liptinite and inertinite indicates a relatively reducing environment, a feature also expressed by the relatively low inertinite content. Examination of the in-seam profiles also indicates undisturbed peat accumulation over long periods of time. The Obed coals, similar in rank and composition to the Hat Creek coals of British Columbia, formed in a freshwater environment and can be used as feedstock for combustion/gasification. Furthermore, the intervals rich in liptinite and petroleum-like substances may be utilized for liquefaction (hydrogenation).

Thermally altered pods of coal of very high rank have been observed in a high-volatile-bituminous coal seam in the eastern side of Eagle Mountain, Elk Valley Coalfield, British Columbia. Rank changes have been measured over a strike distance of 7.5 m from 1.24% to 7.1% R o max , corresponding to a rank gradient of 0.78% R o m −1 . Petrologically, unaltered to extremely altered vitrinite showing nongranular (basic) anisotropy, mosaic-textured liptinite and pyrolytic carbon are the most abundant components. The limited presence of mosaic on vitrinite is an indication that the coal seam may have been weathered prior to being heat-affected. Evidence points to localized temperatures as high as 1,000°C, which could have been caused by a lightning strike. The eastern side of Eagle Mountain has experienced higher temperatures than the western side, and it appears that the heat ‘front’ and zone of alteration have an irregular pattern, pointing to saturation of parts of the coal seam by water. Four types of pyrolytic carbon having distinct morphology, anisotrophy and optical path with increasing temperature were observed. Reflectance of pyrolytic carbon falls within the zone of heat-affected coals, whereas the optical path of heat-affected Seam 15 samples is different from that of fresh coal with increasing rank. Finally, the reflectance of vitrinite in heat-affected coal is higher than the reflectance of vitrinite in carbonaceous shale in the Seam 15 section.

The petrology and depositional environment of a suite of Middle to Upper Devonian coals and carbonaceous shales from Melville Island has been studied. The majority of the coals and carbonaceous shales are cannel coal and canneloids. The sporinite content of cannel coal ranges as high as 80%. The reflectance of vitrinite in cannel coals is suppressed compared with the normal coal from the same area. These coals were deposited in fresh to slightly brackish water in interdelta lobe bays and lacutrine complexes associated with lower delta plain settings as indicated by the boron content (4–71 ppm), petrology (cannel and canneloid) and sedimentology.

A suite of 24 tonsteins from the East Kootenay Coalfields is studied for mineralogical and elemental composition, origin, and the degree of physical and chemical alteration, using x-ray diffraction (XRD), x-ray fluorescence (XRF), instrumental neutron activation analysis (INAA), and inductively coupled plasma (ICP). Concentration of elements greater than the Clarke value is often limited to the litho-philes, i.e., Al. B, Ba, Cr. Co, Cs, Cu, Fe, K, Rb, Mg, Si, Sr, Th, and U, and some chalcophiles, i.e.. As, Sb, Se, and Mo. However, some lithophiles, such as Br, Ca, and CI, are depleted in these samples. The elements Al, Ca, Co, Hf, K, Mg, Na, Th, Se, U, andREEs (rare earth elements) are sensitive indicators of origin and degree of alteration of these tonsteins. Statistical analyses allow indirect observation of the stages of leaching that have affected the tonsteins. The Kootenay tonsteins are divided into two groups based on their mineralogy and elemental composition: (1) tonsteins rich in Ba and...

Thermal alteration of both organic and inorganic components of a coal seam from Telkwa, British Columbia, is examined, using reflected light microscopy, x-ray diffraction (XRD), and neutron activation analysis (INAA). The alteration resulted from intrusion of an alkali basaltic dike. The organic components of coal (macerals) at the contact with the intrusion are coked and developed strong anisotropy. The temperature of formation of this coke is estimated at >750°C and possibly >900°C with a fast rate of heating. However, coal at a distance of 120 cm from the dike is unaltered. Some liptinite macerals retained their original morphology in the altered residue but developed stronger anisotropy than the altered coal groundmass. Pseudovitrinite became reactive and developed fluidity in the altered coals. Original botanical morphology of pseudovitrinite superimposed by mosaic textures is still present in altered coal. Assimilation of less reactive components of coal by reactive components is observed i...

A total of 6292 organic-matter reflectance determinations are given for samples from 140 oil and gas wells (or deviated legs) and 1857 measurements from 346 outcrops or mining drill core from the Arctic Islands. Each sample has a reflectance value, the type of organic matter that was measured, and is assigned to a stratigraphic unit. The data is held at the Geological Survey of Canada, but comes from a wide range of sources including GSC files, David Pearson and Associates, Geo-optics Ltd., TeckCominco Ltd., and Panarctic Oils Ltd reports. A depth vs. Ro plot is given for each oil and gas well.

The nickel species in the feed coals and ash by-products from seven Canadian power plants (including one with a fluidized bed combuster) burning local subbituminous and bituminous coals with sulfur contents ranging from 0.22 to 3.6% have been examined using nickel XANES spectroscopy. XANES spectroscopy of Ni in coal and coal derived ash is complicated by a poor signal : noise ratio due to fluorescence of the much more abundant iron in the coal. Nevertheless, it has proved possible to show that the Ni environment in coals varies from largely oxidic species to mixtures of Ni-containing oxide and sulfide species. The nickel in one oxidized coal appears to be present as nickel sulfate. Nickel in all bottom and fly ash samples examined appears also to be present largely in oxygen anion environments. With the exception of one fly ash sample, for which the Ni exhibited spectral features similar to those for Ni(2+) in spinel or oxide phases, the nickel in the bottom and fly ash samples appears to exist largely as Ni(2+) in environments similar to those reported for Ni in silicate glasses. The data obtained indicate that the presence of potentially carcinogenic nickel sulfides in ash by-products from combustion of these coals is unlikely.

This report summarizes the results of a study carried out on six pulverized coal-fired power plants in western Canada burning subbituminous coal for the mass-balance and speciation of mercury. The main objectives of this study were to: determine the total gaseous mercury (TGM) emitted from stacks of power plants using the Ontario Hydro method; identify the speciation of emitted mercury such as metallic (Hg(0)) and gaseous elemental (GEM) mercury; and perform mass-balance calculations of mercury for milled-coal, bottom ash, electrostatic precipitators (ESP) fly ash and stack-emitted mercury based on three tests. Sampling of mercury was carried out using the Ontario Hydro method and mercury was determined using the USEPA method 7473 by cold vapor atomic absorption (CVAAS). The sample collection efficiencies confirmed that both oxidized and the elemental mercury had been successfully sampled at all power plants. The total gaseous mercury emitted (TGM) is 6.95-15.66 g h(-1) and is mostly in gaseous elemental mercury (GEM, Hg(0)) form. The gaseous elemental mercury is emitted at a rate of 6.59-12.62 g h(-1). Reactive gaseous mercury (RGM, Hg(2+)) is emitted at a rate of 0.34-3.68 g h(-1). The rate of emission of particulate mercury (Hg(p)) is low and is in the range 0.005-0.076 g h(-1). The range of mass-balances for each power plant is more similar to the variability in measured mercury emissions, than to the coal and ash analyses or process data. The mass-balance calculations for the six power plants, performed on results of the three tests at each power plant, are between 86% and 123%, which is acceptable and within the range 70-130%. The variation in mass-balance of mercury for the six power plants is mostly related to the variability of coal feed rate.

Fluorine was determined in 57 samples of coals from western Canada and the Yukon (47 bituminous, 4 subbituminous, 6 lignite) by a pyrohydrolysis method. The range of values is 31–930 ppmw F in dry coal, the lowest values being mainly for the low-rank coals. For bituminous coals most values are in the range 31–580 (mean 174) ppmw F.

The spatial distribution and deposition of lead and zinc emitted from the Trail smelter, British Columbia, Canada, was studied by strategically locating moss bags in the area surrounding the smelter and monitoring the deposition of elements every three months. A combined diffusion/distribution model was applied to estimate the relative contribution of stack-emitted material and material emitted from the secondary sources (e.g., wind-blown dust from ore/slag storage piles, uncovered transportation/trucking of ore, and historical dust). The results indicate that secondary sources are the major contributor of lead and zinc deposited within a short distance from the smelter. Gradually, the stack emissions become the main source of Pb and Zn at greater distances from the smelter. Typical material originating from each source was characterized by SEM/EDX, which indicated a marked difference in their morphology and chemical composition.

Geochemical analysis of elements and organic matter were conducted on vertical profiles of the recent sediments from Pigeon Lake, Alberta, Canada, to determine historical variations in elemental content of the sediments as related to their geochemical fractions. The elements are grouped according to their affinity with different geochemical fractions, by using cluster analysis and sequential extraction experiments. As a result, four elemental fractions were identified: clastic mineral detritus; carbonate; organic; and elements that show less similarity to the previous groups perhaps due to anthropogenic input or the influence of other fractions, such as oxyhydroxides. Following the identification of geochemical fractions in the sediments, a three-step normalizing method was applied using parameters that represent each geochemical fraction. These normalizing techniques appear to be important in verifying whether the variation of elements is indeed the result of anthropogenic and/or natural activities. The normalized data are correlated with the recent history of human activity and natural events near Pigeon Lake. Given the age of the lake sediments, this correlation indicates that the depth profiles of elements after being normalized to the organic and carbonate fractions reflect the variation of detrital input into the lake. However, the former mainly corresponds to the coarse-grained clastic minerals originating from high-energy erosion as the result of natural events (e.g., flooding), whereas the latter corresponds to the low-energy erosion of the fine particles (enriched in lithophile elements) due to deforestation in the drainage basin. Normalizing to the clastic mineral detritus fraction results in the increase of heavy metals in the uppermost part of the sediment profiles, which coincides with industrial activities during the past two decades in central Alberta. However, the concentration of these elements is negligible, as compared to the quantities released by geogenic processes (erosion).

Mean maximum graptolite reflectance values from numerous sections in Arctic Canada range from 0.6% in Cornwallis Island and northwestern Devon Island to 4.7% in Ellesmere Island. We attribute this great lateral reflectance variation to differing burial depths of the graptolite-bearing strata beneath thick synorogenic siliciclastic covers. We attribute the low maturity of rocks in northern Cornwallis and eastern Bathurst islands to a maximum burial of about 2 km. Elsewhere, we used the paleogeographic location and proximity to the Ellesmerian overthrust wedge to interpret the measured reflectance values. In northern Ellesmere Island, where the highest graptolite reflectance values (4.7%) occur, as much as 9.6 km of synorogenic siliciclastics accumulated on a tectonically loaded carbonate shelf. Initial synorogenic siliciclastics encountered substantial submarine-to-basin relief, and thus about 2 km of sediment were deposited prior to the initiation of deposition on the adjacent drowned shelf. Also, the deep-water sequence probably was underlain by attenuated continental crust adjacent to the southeastward-advancing Ellesmerian overthrust wedge. Together, these factors caused deposition of as much as 7.6 km of sediment in western Melville Island and, as much as 9.6 km in northeastern Ellesmere Island. On the drowned shelf, synorogenic stratal thicknesses were less, a feature we attribu e to a thicker, more rigid crustal sequence and greater distance from the Ellesmerian tectonic loading. We expect liquid hydrocarbons to be generated from the organic matter in the shales in areas with a graptolite R0 maximum (GR0 max) of less than 1.7%. The presence of two types of solid bitumens having different reflectances, morphologies, and optical textures suggests that hydrocarbons were generated and migrated through the graptolite-bearing strata. We expect only gaseous hydrocarbons in areas where GR0 max exceeds 2.0% R0.

Higher land plants did not evolve until the Late Silurian. Therefore most pre-Devonian rocks are devoid of vitrinite, making it difficult to assess the thermal maturity of their organic matter using standard optical methods. Pre-Devonian sediments do contain structured marine-derived organic matter including algae, chitinozoa, graptolites and scoleco-donts together with amorphous material and bitumen.

Organic-rich radioactive shales are a common regional feature resting on Cretaceous transgressive surfaces in western Canada. The basal shale in the Shaftesbury Formation (Late Albian) from the Peace River area of northern Alberta is characterized by high gamma-ray, high resistivity, and low neutron wireline log signatures. Three facies, in ascending order, are present within the basal Shaftesbury Formation: 1) a brackish-water estuarine shale; 2) a restricted, marginal-marine shale which is radioactive; and 3) an open-marine, normal salinity shale. The radioactive shale contains an abundance of large, lenticular algal cysts (cf. Lancettopsis lanceolata Madler 1963) which are rare in overlying and underlying shale. The algal cysts and high organic content may be the locus of th radioactivity. The total organic carbon content ( 6%) and sulphur content ( 3.4%) of the radioactive shale also are higher than the shale above and below, with a different mineralogy as well. The radioactive portion of the basal Shaftesbury shale has the characteristics of a condensed section; it is directly above a ravinement surface and transgressive-lag deposit which, in turn, locally overlie estuarine sediments deposited within an incised valley. Other characteristics include evidence of low oxygen values, low concentrations of benthonic foraminifera, and evidence of a slow sedimentation rate. Palynological, micropaleontological, and geochemical results indicate that the radioactive s ale was deposited in restricted, marginal marine conditions and that overlying shale shows a progressive deepening to nearshore, open-marine conditions. This radioactive shale does not represent the deepest water sediments of the transgression but is a condensed section deposited in relatively shallow water.

The concentration of 58 elements in Byron Creek coals ( % Ro = 0.942 1 .05 ), and their 1000 °C ashes were determined using intense neutron activation and plasma emission spectrometry. The organic-inorganic affinities of elements were detected by the trend of element concentration versus ash content of the samples. Antimony, boron, bromine and selenium are the only elements that are enriched in these coals. The higher concentration of boron in one coal seam is considered to indicate that this seam was deposited in a more marine environment than the other seams. Coal seams can be identified by the concentration or depletion of certain trace elements, such as boron, sodium, thorium and uranium. Similarity indices of coal samples are also a useful tool in seam identification. Certain elements, for example gallium, thorium and uranium, are more concentrated in carbominerite from the roof or floor than within the coal. Regular variation of boron, sodium, thorium and uranium may indicate the repetition of certain units in tectonically thickened coal seams.

The variability in reflectance of huminite (texto-ulminite, eu-ulminite A and B, different types of corpohuminite) and liptinite groups of macerals in subbituminous coals was examined using reflected light microscopy. All macerals were selected from coal and interbedded carbonaceous shale and carbonate sediment samples from the 515-m-thick coal deposit No. 2 located in the Hat Creek valley of south-central British Columbia. The measurements obtained reveal that, in addition to burial depth, reflectance distribution depends on maceral subtypes and associated mineral matrix. Huminite in the coals and sediments (kerogen) consists mainly of humotelinite, with eu-ulminite B being the dominant maceral sub-type. Reflectance values determined on huminite in coals and Type IIIb kerogen increase from eu-ulminite A and phlobaphinite type 1 through eu-ulminite B and phlobaphinite type 2 to gelinite. The reflectance of all five huminite maceral subtypes studied increases with depth. However, the increase of phlobaphinite type 1 and gelinite reflectance with depth is irregular. A comparison of the reflectance values obtained for the same maceral subtype (eu-ulminite B) from the interbedded coal, shale and carbonate samples records consistent differences, implying some dependence of the reflectance (and perhaps rate of organic maturation) on the mineral matrix. Generally, the highest eu-ulminite B reflectance was recorded from carbonate rocks and the lowest from shale, whereas coal matrix produced intermediate values. At present, it is not known whether differences in reflectance of eu-ulminite found in the above lithologies are due to differential retention, efficiency of reaction products removal, thermal conductivity of the lithologies, or existence of a calcium carbonate catalyst.

Isotropic to anisotropic pyrolytic carbon was observed in Canadian subbitumonous to bituminous coals (% R oil = 0.50−1.0) using reflected light microscopy. Morphologically, pyrolytic carbon consiste of large, well-developed spherulitic and laminated forms occuring in coal macerals and carbominerites as cell and crack filling. The spherulitic forms probably developed rapidly and laminated forms over a period of time. The presence of pyrolytic carbon in coal may indicate a thermal event and, in these coals it is of detrital nature and therefore should be grouped with inertodetrinite.

The occurrence of coal is related directly to the climate of a given geological age which, in turn, is determined by the extent of the seas, regional geography, the configuration of the land masses and therefore, by the ongoing process of continental drift. Of major importance also is the relative vertical movement of the coal-forming basins, resulting from tectonic movement, which affects the rate of burial and the coalification process. In this review the changes in climate and continental positions, relative to coal formation, are described from the early Carboniferous to the Tertiary. The genetic relationships between different coalfields, in terms of the flora of the period are commented upon and it is suggested that by studying the palaeogeography of the world it is possible to correlate apparently unrelated coalfields.

The effects of atmospheric oxidation at 378 K upon the carbonization of a coking and a caking vitrinite have been examined in terms of the origins and extents of development of anisotropic material. The vitrinites, oxidized from 1 to 40 days, were carbonized to temperatures between 618 and 878 K, in open boats under nitrogen at atmospheric pressure, and in sealed gold tubes at maximum pressures of 140 to 310 MPa. Optical microscopy was used to observe, qualitatively, changes in reflectance and in shape and size of the anisotropic material of the carbonized product; morphological changes were monitored by scanning electron microscopy. For both vitrinites, whereas one day of oxidation destroyed coking properties and almost all of the anisotropic development in the open-boat carbonizations, the pressure carbonizations were not significantly affected until after five days of oxidation. Anisotropy still developed by mesophase growth from the plastic phase of carbonization, to produce the shaped, botryoidal material characteristic of pressure carbonizations. Thereafter, although in the pressure carbonizations the particles of coking vitrinite only fused slightly at interfaces to form a coherent product, marked increases occurred in reflectance and in observed anisotropy, showing maxima at nine days of oxidation. Results are interpreted on the assumption that oxidation cross-links the macromolecular structure of the vitrinite substance. The effect of high pressure during carbonization after five days of oxidation is to preserve and perfect the original basic anisotropy of the vitrinites initially stabilized by the cross-linkage of oxygen atoms.

Three vitrinites (C = 80.0, 87.9 wt%, daf and 94.2 wt%, dmmf) have been heat-treated over the temperature range 1000–2400 °C in the presence of argon. The variation of morphological and optical properties of the heat-treated samples is studied systematically using reflected-light microscopy. An optically isotropic, highly reflecting material is formed on the surface of anisotropic particles of two of the vitrinites (C, 80 and 94.2 wt%) during semi-graphitization (1000–1400 °C), which decreases in extent with increasing temperature and is absent at the end of this stage. The development and subsequent disappearance of the isotropic material is probably due to the evolution of volatile matter and subsequent deposition of pyrolytic carbon during semi-graphitization. The continuous increase of bireflectance of these two vitrinite residues, with heat-treatment temperature, indicates progressive improvement in the ordering of the molecular structure. The reflectance of the heat-treated anthracitic vitrinite (C, 94.2 wt%), increases continuously whereas the reflectance of the heat-treated low-rank vitrinite (C, 80 wt% decreases slightly from a maximum during semi-graphitization. The third vitrinite (C, 87.9 wt%) does not develop an optically isotropic highly reflecting material on particle surfaces during semi-graphitization. However, this vitrinite softens during carbonization (25–1000 °C) producing a residue with a mosaictype anisotropic microstructure. The condition of polished surfaces prepared from residues of this vitrinite from the semi-graphitization to crystallization stages (1000–2300 °C) deteriorates, values of bireflectance and reflectance decrease continuously with increasing temperature. This appears to result from a reduction in the surface hardness of particles of this vitrinite residue resulting on transformation from two-dimensional ordering to three-dimensional graphitic ordering.

Reflectance data from three bore cores in Scania, southern Sweden, are characteristic of moderately aromatic carbon species. The variation in graptolite reflectance is minimal, suggesting similar levels of thermal maturation. Measurements from graptolites associated with pyrite or carbonate are unreliable for maturation assessment. The graptolites display low anisotropy and have not been directly affected by the heat from numerous Permocar-boniferous dikes in Scania. The reflectance of the graptolites has been correlated with conodont alteration index and also indirectly with vitrinite reflectance indicating a thermal maturation level generally associated with the onset of dry gas generation. Dispersed bitumen in the shales probably migrated from sediments of lower thermal maturity.

The reflectance and bireflectance of graptolite fragments (Silurian-Ordovician) from southeast Turkey were examined and the morphology was described using reflected light microscopy. The dispersion of maximum and minimum reflectance of graptolites sectioned parallel and perpendicular to the bedding was also determined. The graptolites were anisotropic and the anisotropy was stronger for sections perpendicular to the bedding. The graptolite fragments show two types of surface morphology: granular and non-granular. The granular type had a rough surface and granular anisotropy, the non-granular fragments showed a smooth surface and basic anisotropy. The fine internal structure of graptolite was evident under crossed-polars. The reflectance of graptolite increased with depth and was higher than other organic material, e.g. bitumen, found in the same sediment. The present study indicates that the reflectance of graptolite in sediment can be used to determine the maturity of the dediment.

The upper Eocene Hat Creek coal deposits of British Columbia, Canada, are one of the thickest lignite to subbituminous coal deposits of the world, and comprise 350–550 m of coal. Samples of sedimentary organic material were taken from a 560-m interval of interbedded shale, siltstone and carbonate that was penetrated by corehole 75–106 in the centre of the coal basin, and the reflectances of huminite (eu-ulminite) from coal and kerogen from the organic material were determined and petrographical analyses were made. The coal deposit contains many leaf- and resinite-rich horizons, and the reflectance of huminite in these horizons in lower than in corresponding horizons containing less liptinite. When compared with huminite in adjacent coal beds, the reflectance of huminite in shale is lower, that in siltstone is similar, and huminite associated with carbonate rocks has slightly higher reflectance values. The petrological variation in the coal is mainly within the huminite group of macerals. The coal at the top of the deposits is lignite (% R o = 0.38) and becomes subbituminous C (% R o = 0.50) at the base. The inertinite content is very low, indicating a low level of peat fire or oxidation. The early stages of transformation of gelinite to macrinite are described. The paleoenvironment appeared to be lacustrine, as determined by organic petrological analysis of coals and interbedded sediments. Four major zones, each containing many subzones, were found. Paleoenvironments were similar for the A and C zones and also for the B and D zones.

Maturity and source rock potential of organic rich beds in the Triassic Schei Point Group in the Sverdrup Basin, Arctic Canada have been investigated using reflected light microscopy and the results are compared with other maturity parameters determined geochemically (i.e. Rock Eval, and biomarker maturation parameters). The samples evaluated belong to the Eden Bay Member of the Hoyle Bay Formation and contain a predominance of marine algal material, in the form of Tasmanales , and dinoflagellates, along with mixed terrestrial organics. The rock matrix is dominantly carbonate with some shaly input, indicating that the rocks were deposited in an iron-poor highly euxinic environment. With few exceptions there is good agreement between parameters,determined using microscopy; namely % R o , λ max and R GQ and geochemical parameters, T max , HI , Dia C 27 Dia C 27 + reg C 27 steranes, S (S+R) C 29 steranes. The ternary diagram showing the abundance of normalized C 27 , C 28 and C 29 regular steranes indicates a mostly marine depositional environment for the Schei Point source rock. This is confirmed by the abundance of marine fauna and flora in these samples. Analytical results from several different techniques indicate that the source rocks become more mature from the margin towards the axis of the Sverdrup Basin. This is due, in part, to the increase in overburden of sediments in the axis of the basin. Also the high thermal conductivity of salt has strongly influenced the maturity of Schei Point source rocks over the crest of the salt cored structures, i.e. Well Hazen F-54, and the proximity of salt has enhanced maturation levels at Well Rock Point J-43. The sections investigated were also considered to have an excellent gas potential due to their higher than average TOC content.

A comparison was made between the data obtained using the Zeiss image analyser (IBAS) and those obtained by conventional methods, using polished, particulate and blocks of coal. The results obtained by using the two methods are in good agreement.IBAS is an automatic system and reduces the data (reflectance measurement and point count analysis) collecting time substantially, compared with conventional methods. Seam profiles, based on polished blocks, can be constructed rapidly using IBAS to determine the paleoenvironment of coal deposition or the position of macerals resistant to grinding. Also, evaluation and presentation of large numbers of coal samples can be performed in a short time by using polished, particulate blocks.

The present study examines the reflectance and petrology of a self-burning coal wastepile from Coleman, Alberta, Canada. Unaltered coal, carbonization, combustion and ash zones have been identified in the section studied. Due to the presence of uncompacted coal fragments, air can circulate easily through open fractures acting as conduits for convecting gases. Heat generated by the combustion of coal has altered the coal to produce solid (semicoke/coke), liquid (tar) and volatile matter. Several types of tar have been recognized penetrating cracks in the residues, briquetting coal macerals or reacting with coal particles. It has been estimated that the coal was carbonized at a temperature of 500–550°C at a rate of heating of 10°C/min and subsequently combusted at a higher temperature (550–600°C). When comparing the optical and petrological profile of the Coleman self-burning coal wastepile with that of other burning coal seams in Western Canada, certain similarities and differences become apparent.

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.

Vein, lens and stratiform natural sedimentary bitumen deposits were analysed by combined geochemical and micropetrographic techniques. Reflectances in oil, air and water, fluorescence spectral properties, solubility in dichloromethane, elemental analysis and bulk chemical composition of soluble fractions by chromatographic separation indicate that these materials are generally gilsonite bitumen, although some, showing evidence of significant alteration and weathering, are closer to albertite in composition. Optical properties show that the bitumens are immature and fall within the field of asphaltites on the bituminization curve. Fluorescence spectra generally show two maxima, again a feature associated with immature gilsonite bitumen. Capillary-column g.c. of saturates fractions indicates the absence of normal and acyclic isoprenoid alkanes, these fractions being dominated by a series of C27-C34 pentacyclic triterpanes of the hopane family. The saturates fraction composition is characteristic of biodegraded crude oils, and molecular biomarker stereochemistry indicates a moderately mature petroleum source. All the bitumens are shown to have a common genetic origin and are thought to be the result of in situ alteration and biodegradation of oil infillings in joints, fractures and bedding planes, resulting from fracturing and faulting of reservoir and overlying cap rocks associated with a period of Neogene tectonism.

Vitrinite-rich samples from a weakly caking and a strongly coking coal have been carbonized both fresh and after preoxidation for 14 days at 105 °C to points within the temperature range 300–800 °C. Conventional reflected-light microscopy shows that pronounced reduction in softening capacity and devolatilization of carbonized preoxidized reactive macerals are accompanied by microscopical features which contrast with those of the same reactive macerais when carbonized fresh. Most noticeable is the retention of the original petrographical structure of the coals when carbonized after preoxidation, even at temperatures of 800 °C. No mosaic is formed in the preoxidized reactive macerals, although a general anisotropy gradually develops; some vitrinitic particles attain a very high degree of anisotropy though all of this development takes place in the solid state. The level and trends of the average bulk bireflectances of both forms of carbonized vitrinite are similar, but the rapid bireflectance rise characteristic of vitrinites carbonized above ≈ 600 °C probably begins earlier in preoxidized than in fresh vitrinites. This could happen if preoxidation raises the aromaticity of the original vitrinite, so allowing reorientation of the lamellae to begin at lower temperatures. Comparisons are made with earlier observations.

The dispersion of optical properties (e.g. reflectance, refractive and absorptive indices) of graptolite epiderms in early Paleozoic sediments with low to high maturity levels (conodont alteration index = 1–5) has been determined in the visible spectrum (450–650 nm). The results were compared with those for vitrinite of different rank and asphaltic pyrobitumen. The dispersion follows similar trends to those of coal macerais such as resinite, vitrinite, and also asphalt and pyrobitumen. This indicates similar molecular structural changes, e.g. an increase in aromaticity and ordering of aromatic carbons for graptolite epiderms with increased maturity. The dispersion of optical properties of graptolites in sediments with a low maturity level falls from blue to red in the visible spectrum, indicating low aromatic carbon content. Those in more matured sediments rise from blue to red indicating high aromaticity and molecular ordering for these graptolites. Graptolite epiderms are sensitive to a rise in temperature and are a good indicator of the maturity of early Paleozoic sediments.

The "Mammoth" coal seam in southeastern British Columbia, Canada, was structurally thickened to 100 m as a result of Laramide folding and faulting. Samples from the coal seam, examined using reflected-light microscopy, include thermally altered coal macerals, their by-products (e.g., pyrolytic carbon), and, in addition, heat-affected preoxidized coke.The heat-affected residues are composed of material formed by friction produced from faulting of the coal-bearing strata. The pyrolytic carbon was formed from the distillation of coal and from coal tar pitch.The occurrence of preoxidized, heat-affected vitrinite suggests that the Mammoth coal seam was oxidized before faulting.

Liptinitic macerals in medium and low-volatile bituminous coals (C=87.9 and 90.0 wt% daf) which have undergone a plastic stage during primary carbonization (

Samples of the Lower Carboniferous Emma Fiord Formation from two localities in the Sverdrup Basin of Arctic Canada were examined using reflected white and fluorescent light. The samples from Kleybolte Peninsula on Ellesmere Island show a relatively high level of thermal maturity. In contrast, those from Grinnell Peninsula on Devon Island are immature to marginally mature and include subbituminous coals and oil shales. Two types of oil shales are distinguished on the basis of liptinite content, mineral matrix, RockEval pyrolysis analysis, and concentration of boron. One is characterized by a liptinite-rich, clay-carbonate matrix with a relatively high hydrogen index and boron content, and the other by a liptinite-poor carbonate matrix with a relatively low hydrogen index and boron content. Hydrogen-rich components of these shales consist of alginite, matrix bituminite and minor amounts of exsudatinite and sporinite. Kerogen Types III and IV comprise only minor components of the organic matter. Thermal maturity of the Grinnell Peninsula oil shales increases with depth. Matrix bituminite in these oil shales has seeped into cavities and microfractures in the kerogen Types III and IV, forming exsudatinite. The distribution and character of the organic constituents and also the concentration of boron in these samples indicate a fresh to brackish water environment.

Coal samples from the 170-m-thick A zone of the Hat Creek coal deposit No. 1 in central British Columbia were examined for major-, minor- and trace-element distribution. The coal is lignite/ subbituminous in rank and of Eocene age. This study shows: (1) As, B, Br, Cl and S are the only elements organically associated in these samples; (2) Concentration of certain elements such as Fe, Mn and Co can be related to the presence or absence of carbonate and/or sulphide minerals; (3) Distribution of certain elements, (i.e. Al, B, Br, Cl, Cr, Fe, Th, U and Zn) follow similar patterns of concentration or depletion across the vertical thickness of Zone A and suggest three depositional cycles; (4) Concentration of boron versus chromium, sodium, sulphur and uranium for these coals clearly placed them in a freshwater environment; (5) Rates of sedimentation using the Na/K ratio also suggest three depositional cycles; (6) In resinite samples, hand-picked from these coals, the concentrations of all elements except As and Se were lower than their concentrations in the whole coals.

Chemical and petrological analyses were carried out on several British Columbia coals which are known as ‘needle’ coals because of the pine needle morphology exhibited on weathering. The object was to determine the nature of the precursor and thus to identify the component maceral as resinitic or algal. Infrared spectroscopy, saturate fraction gas chromatography, pyrolysis chromatography, gas chromatography-mass spectrometry, organic elemental analysis and reflectance and fluorescence microscopy were used. While the i.r. properties are consistent with previously published results on resinite, the other chemical results suggest that the present materials are not obviously related to any given member of the liptinite group of macerals. High concentrations of extractable hopanoid hydrocarbons are interpreted as resulting from high contribution to the biomass by bacterial debris. The petrological results suggest that the main constituent of the ‘needles’ can be best described as bituminite II or III derived from non-algal lipids. This conclusion is also supported by the observed associations of the other identifiable macerals. The results indicate that the ‘needles’ have been chemically and petrologically homogenized from a liptinite-rich precursor with minimal algal input. The present morphology may have been preserved from resin rodlets which have been severely altered by catagenetic or biological mechanisms or both.

A partially combusted and coked coal seam from Aldridge Creek, British Columbia, Canada, was studied using reflected light microscopy. Three zones, namely combustion, distillation and unaltered coal were detected. Combustion had taken place in the uppermost part of the coal seam, immediately below the melted roof rock, the only evidence of combustion being the presence of coke showing oxidation rims. The distillation zone encompassed most of the coal seam; different stages of carbonization were evident in the samples from this zone, with a coke subzone occurring at the top and a precarbonization subzone at the base. Samples from the coke subzones show granular anisotropy; the reflectance and bireflectance of medium grained mosaic are higher than those measured on fine grained mosaic in the same samples from this zone. An unaltered coal zone occurred at the base of the coal seam.

The source of the oil at Norman Wells has long been assumed to have been the Canol Formation and/or the Bluefish Member of the Hare Indian Formation. These two units are stratigraphically above and below the Kee Scarp Formation reservoir unit respectively, and are both bituminous shales. A wide range of analytical techniques including Rock-Eval pyrolysis, solvent extraction and fractionation, capillary gas chromatography, gas chromatography-mass spectrometry, and white light and fluorescence microscopy has been used to characterize core samples of these two units and two samples of crude oil from the Norman Wells field. Most of the analytical techniques were insufficiently refined to either differentiate the extracts from each other or to make a definitive oil/source rock correlation. Collision activated decomposition coupled with multiple ion detection mass spectrometry (GC-MS-MS) did provide sufficient chemical compositional detail of the oils and the two potential sources to demonstrate that the Canol Formation has been the effective source of the Norman Wells oil whereas the Bluefish Member has not. Petrological analysis of the organic fractions also indicates that although the bulk organic composition of both units may be classified as Type II organic matter, significant differences exist between them. The Bluefish Member contains substantial amounts of megaspores, whereas the organic matter in the Canol Formation is largely phytoplankton debris. The level of thermal maturity of the core samples ranges from immature to moderately mature in the vicinity of the Norman Wells field to overmature for the samples obtained to the west and north of the field. The level of thermal maturity of the oil was observed to be somewhat higher than that of the samples of the source formation directly above the field. It was thus inferred that some lateral migration from more mature areas has occurred but the extent of this migration was not necessarily more than a few to tens of kilometers.