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In the Deer Lake Basin of western Newfoundland, Canada, analcime has been found within fine‐grained, siliciclastic and carbonate, lake and lake‐margin sediments of the Carboniferous Rocky Brook Formation. Analcime is the only zeolite observed in these unmetamorphosed and non‐volcanogenic rocks. Microscopic analcime occurs as vug‐filling, limpid, isotropic to anisotropic crystals. Microprobe analyses show this type of analcime to be lower in silica than most analcime in sedimentary rocks. A second textural type of finer‐grained submicroscopic analcime can be detected from X‐ray diffraction spectra of Rocky Brook Formation mudstones, where it is associated with phyllosilicates (illite, interstratified chlorite/smectite, smectite, chlorite), other silicates (quartz, feldspar) and carbonates (dolomite, calcite). Results of this study suggest that the analcime in the Rocky Brook Formation formed either by direct lakewater/porewater precipitation or by reaction of these waters with one or more clay mineral types or plagioclase.

The Deer Lake Basin is an entirely non‐marine basin associated with the Cabot fault zone. Structural and stratigraphic evidence strongly suggest dextral strike‐slip movements along the fault zone during Tournaisian‐Visean time. Two elongated, end‐on structural blocks (probable positive flower structures) contain fold axes and second‐order faults oriented obliquely to fault traces bounding the blocks, in a manner implying dextral movements. In one part of the basin, the stratigraphic thickness of a long homoclinal section of later basin‐fill sediment (Deer Lake Group) greatly exceeds the suggested depth to basement based on gravity measurements, a situation common to strike‐slip basins. Formations representing basin fill can be arranged into megasequences (from oldest to youngest: Anguille Group, Wetstone Point and Wigwam Brook Formations, Deer Lake Group, Howley Formation) corresponding to lateral growth stages of the basin. Gravity, magnetic, and seismic data show that depths to basement on either side of the end‐on flower structures are comparable, so that the youngest strata in the basin (Howley Formation) are not underlain by earlier basin fill. These geophysical data, therefore, corroborate the geological conclusion of onlapping stratigraphic relations. The geophysical data suggest participation of basement in Carboniferous gravity faulting and show the location of the subsurface extension of the Taylors Brook Fault in the western part of the Deer Lake Basin. Thermal maturation of the Anguille and Deer Lake Groups, as measured by vitrinite reflectance, clay mineral assemblages, illite crystallinity, and Rock‐Eval pyrolysis, indicate a much higher level of maturation for the Anguille than for the Deer Lake Group. Palaeotemperatures for the Anguille and Deer Lake Groups are estimated to be around 200 and 100oC, respectively, suggesting that Anguille Group rocks are overmature whereas Deer Lake Group strata are within the oil‐generating window. Onlapping stratigraphic relations and areally homogeneous time/temperature effects, however, have created a situation in which the Deer Lake Group and Howley Formation have similar maturation levels.

Coal samples from the Barachois Group of western Newfoudland vary in rank from high-volatile C to high-volatile A. The coals are vitrinite rich (>70%), except some from Coal Brook that contain substantial quantities of inertinite (up to 52%). Liptinite ranges up to 18% but is a relatively minor component. The most abundant constituents amongst the three maceral groups are vitrinite -vitrinite A, inertinite-semifusinite, and liptinite-sporinite. Compositional profiles in three of the seams show no clear correlation between maceral group content and stratigraphic position. The Barachois Group coals are relatively high in ash (mean = 12.8%) and sulphur (mean = 6.9%). Spore assemblages from coal samples of the Barachois Group indicate a Westphalian A age in the Barachois Brook and Coal Brook areas and a Westphalian C age along Blanche Brook.Barachaois coals are part of a mudstone-dominated facies association that developed in an assemblage of floodplain environments. Plots of tissue preservation -gelification indices (TPIJGI) and the assemblages of spores derived from vascular plants suggest that most peats were generated in wet, forested tracts that, from the high ash content, occupied low-lying interfluves. Less wooded fen environments are also indicated, particularly in the Blanche Brook seams, by TPIIGI plots and a spore assemblage suggesting incursion of flood waters and dominance of herbaceous vegetation. Inertinite-rich samples from Coal Brook show extreme variation in paleoenvironmental conditions, which include dry forested regions.Les Cchantillons de charbon du Groupe de Barachois, dans la partie occidentale de Terre-Neuve, sont classifiCs de hautement volatil C B hautement volatil A. Les charbons sont riches en vitrinite (>70%), sauf certains provenant de Coal Brook, qui contiennent des quantitks importantes d'inertinite (jusqu'i 52%). La liptinite peut atteindre des proportions de 18%, mais il s'agit d'un composant relativement peu abondant. Les constituants les plus abondants panni les trois groupes de macCraux sont : vitrinite -vitrinite A, inertinite-semifusinite et liptinite-sporinite. Les variations de composition au travers les couches de charbon ne montrent pas de corrClation tvidente entre la teneur des groupes de macCraux et la position stratigraphique. Les charbons du Groupe de Barachois produisent des proportions relativement ClevCes de cendre (moyenne = 12,8%) et de soufre (moyenne = 6,9%). Les associations de spores dans les Cchantillons de charbon du Groupe de Barachois rkvtlent un Ige westphalien A pour les rCgions de Barachois Brook et de Coal Brook, et un 2ge westphalien C le long de Blanche Brook.Les charbons de Barachois sont incorporCs dans un ensemble de facits, reprCsentC principalement par des mudstones sCdimentts dans une plaine d'inondation. Les diagrarnrnes des indices de prkservation de tissus -gklification (IPTIIG) et les associations de spores derivkes de plantes vasculaires suggbrent que la tourbe a ttC genCrCe en grande partie dans des Ctendues forestibres humides qui, d'apr...

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