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B.S. Pierce

Publications and source records attributed to B.S. Pierce.

At least 19 recordsLinked to original sources
USGS2003

Palynology, petrography and geochemistry of the Sewickley coal bed (Monongahela Group, Late Pennsylvanian), Northern Appalachian Basin, USA

Forty-two bench samples of the Sewickley coal bed were collected from seven localities in the northern Appalachian Basin and analyzed palynologically, petrographically, and geochemically. The Sewickley coal bed occurs in the middle of the Pittsburgh Formation (Monongahela Group) and is of Late Pennsylvanian age. Palynologically, it is dominated by spores of tree ferns. Tree fern spore taxa in the Sewickley include Punctatisporites minutus, Punctatosporites minutus, Laevigatosporites minimus, Spinosporites exiguus, Apiculatasporites saetiger, and Thymospora spp. In fact, Punctatisporites minutus was so abundant that it had to be removed from the standard counts and recorded separately (average 73.2%). Even when Punctatisporites minutus is removed from the counts, tree fern spores still dominate a majority of the assemblages, averaging 64.4%. Among the tree fern spores identified in the Sewickley coal, Thymospora exhibits temporal and spatial abundance variation. Thymospora usually increases in abundance from the base to the top of the bed. Thymospora is also more abundant in columns that are thick (>100 cm) and low in ash yield (< 12.0%, dry basis). Calamite spores (e.g. Calamospora spp., Laevigatosporites minor, and L. vulgaris) are the next most abundant plant group represented in the Sewickley coal, averaging 20%. Contributions from all other plant groups are minor in comparison. Petrographically, the Sewickley coal contains high percentages of vitrinite (average 82.3%, mineral matter-free (mmf)), with structured forms being more common than unstructured forms. In contrast, liptinite and inertinite macerals both occur in low percentages (average 7.7% and 10.0%, respectively). Geochemically, the Sewickley coal has a moderate ash yield (average 12.4%) and high total sulfur content (average 3.4%). Four localities contained a high ash or carbonaceous shale bench. These benches, which may be coeval, are strongly dominated by tree fern spores. Unlike the lower ash benches, they contain low percentages of vitrinite, which mainly occurs as unstructured vitrinite, and higher liptinite and inertinite contents. The accumulated data suggest that the Sewickley paleomire was probably a rheotrophic, planar mire that had a consistent water cover. This is supported by the high vitrinite contents, moderate ash yields, and high total sulfur contents. The high ash and carbonaceous shale benches probably represent either periods of dryness and substrate exposure, or flooding of the mire surface, the duration of which is unknown. ?? 2003 Elsevier B.V. All rights reserved.

International Journal of Coal Geology↗
USGS2001

Geology, coal quality, and resources of the Antaramut-Kurtan-Dzoragukh coal field, north-central Armenia

The Antaramut-Kurta-Dzoragukh (AKD) coal deposit is a previously unrecognized coal field in north-central Armenia. Coal has been known to exist in the general vicinity since the turn of the century, but coal was thought to be restricted to a small (1 km2) area only near the village of Antaramut. However, through detailed field work and exploratory drilling, this coal deposit has been expanded to at least 20 km2, and thus renamed the Antaramut-Kurtan-Dzoragukh coal field, for the three villages that the coal field encompasses. The entire coal-bearing horizon, a series of tuffaceous sandstones, siltstones, and claystones, is approximately 50 m thick. The AKD coal field contains two coal beds, each greater than 1 m thick, and numerous small rider beds, with a total resource of approximately 31,000,000 metric tonnes. The coals are late Eocene in age, high volatile bituminous in rank, relatively high in ash yield (approximately 40%, as-determined basis) and moderate in sulfur content (approximately 3%, as-determined basis). The two coal beds (No. 1 and No. 2), on a moist, mineral-matter-free basis, have high calorific values of 32.6 MJ/kg (7796 cal/g) and 36.0 MJ/kg (8599 cal/g), respectively. Coal is one of the few indigenous fossil fuel resources occurring in Armenia and thus, the AKD coal field could potentially provide fuel for heating and possibly energy generation in the Armenian energy budget. Published by Elsevier Science B.V.

International Journal of Coal Geology↗
USGS1996

Quality and petrographic characteristics of Paleocene coals from the Hanna basin, Wyoming

Coal beds from the Ferris and Hanna Formations, in the Hanna basin, south-central Wyoming, exhibit distinct differences in ash yield, sulfur content, and petrographic and palynologic constituents. These differences are interpreted to be controlled by tectonic changes of the Hanna basin and adjoining uplifts during evolutionary development, which, in turn, controlled mire chemistry and sedimentation. These conditions created two very different settings under which the peats developed during deposition of the Ferris and the Hanna Formations. In addition, there appears to be a geographic (latitudinal) and/or climatic control on the coal characteristics manifested by major differences of Paleocene coals in the Hanna basin compared to those in the Raton basin in Colorado and New Mexico and the Powder River basin in Wyoming.Coal beds from the Ferris and Hanna Formations, in the Hanna basin, south-central Wyoming, exhibit distinct differences in ash yield, sulfur content, and petrographic and palynologic constituents. These differences are interpreted to be controlled by tectonic changes of the Hanna basin and adjoining uplifts during evolutionary development, which, in turn, controlled mire chemistry and sedimentation. These conditions created two very different settings under which the peats developed during deposition of the Ferris and the Hanna Formations. In addition, there appears to be a geographic (latitudinal) and/or climatic control on the coal characteristics manifested by major differences of Paleocene coals in the Hanna basin compared to those in the Raton basin in Colorado and New Mexico and the Powder River basin in Wyoming.

Conference Paper↗
USGS1996

Petrography, geochemistry and palynology of the Stockton coal bed (Middle Pennsylvanian), Martin County, Kentucky

The Middle Pennsylvanian (Westphalian D) Stockton (also known as the Broas) coal bed of the Breathitt Formation is an important energy resource in Kentucky. Petrographic, geochemical and palynologic studies were undertaken from mine, core and highway exposures in Martin and northern Pike counies, Kentucky, in order to determine the influence of the Stockton depositional ecosystem on those parameters. Vitrinite-rich Stockton lithotypes are dominated by Lycospora . Dull lithotypes, including both high- and low-ash yield durains, generally have abundant Densosporites , suggesting that the parent plant inhabited a fairly wide range of environments. Lithologies having tree ferns as an important component also have high fusinite + semifusinite and a low telinite/gelocollinite ratio. The aerial root bundles of the tree ferns were susceptible to oxidation and, for tissue not oxidized to inertinite, to preservation as gelocollinite. In the initial stages of formation, the Stockton mire was discontinuous and had a rather restricted floral assemblage. The presence of durains higher in the Stockton section, particularly the low-ash yield durains having petrographic indicators of degradation, suggests that portions of the mire developed as a domed peat. The termination of the mire as a high-sulfur, arboreous lycopod-domimated mire is consistent with the return to more planar mire development.

International Journal of Coal Geology↗
USGS1994

Isotopic evidence for the source of sulfur in the Upper Freeport coal bed (west-central Pennsylvania, U.S.A.)

Sulfur isotopic variations were used to determine the sources of sulfur in a medium-sulfur coal (???2 wt%S) that lacked marine influence, which is often cited as a major source of sulfur in coal. Variations in the amount and isotopic composition of the organic and pyritic sulfur among the coal-bed facies of the Upper Freeport coal bed (Middle Pennsylvanian) are attributed to differential incorporation of syngenetic and epigenetic sulfur. These variations reflect varying environmental conditions during paleopeat formation, porosity and permeability, and the availability of sulfate and iron. A large increase in the abundance and sulfur isotopic value of pyritic sulfur in the upper facies of the coal bed, in proximity to the overlying lacustrine shale, corresponds to an increase in massive and irregular forms of pyrite. This relationship is attributed to at least two stages of epigenetic pyrite incorporation. An early stage of epigenetic pyrite, moderately enriched in 34S, apparently formed during the fluvial-lacustrine period immediately following peat accumulation. A late stage of epigenetic pyrite, highly enriched in 34S, formed after compaction of the original peat as cleat- and fracture-filling pyrite; this sulfur was probably derived from bacterial reduction of dissolved sulfate in groundwater. Isotopic mass-balance calculations indicate that this late-stage epigenetic pyrite may account for up to ???50% of the pyritic sulfur in some upper facies of the coal bed. These results suggest that most of the pyritic sulfur in the Upper Freeport coal bed may be epigenetic, incorporated either soon after peat accumulation or later during coalification. ?? 1994.

Chemical Geology↗
USGS1993

A preliminary review of coal exploration activities conducted by the government of Armenia and the coal resource potential of Armenia

A coal resource assessment team from the U.S. Geological Survey (USGS), in cooperation with the Armenian Department of Underground Resources (DUR) and elements of the Ministry of Energy and Fuel, has completed an initial visit to Armenia under the auspices of the U.S. Agency for International Development JUSAID). The visit included discussions of the coal resources, identification of problems associated with on-going exploration and development activities, and field visits to selected solid fuel areas. The USGS team will return in November with a draft of the final report for discussion of conclusions and recommendations with Armenian counterparts, representatives of USAID, and the American Embassy. The final report, which will contain tabulated coal-sample analytical results and detailed recommendations, will be submitted to the USAID by the end of December 1993. Preliminary conclusions are that: 1) Armenia has usable deposits of coal that could form a viable, though relatively small, component of Armenia's energy budget; 2) on-going exploration and development activities must be augmented and expedited to increase understanding of the coal resource potential and subsequent utilization; 3) deficiencies in supplies (primarily fuel) and equipment (replacement of aging parts and units) have greatly reduced the gathering of necessary resource data; and 4) training of Armenian counterparts in conducting and managing coal exploration activities is desirable.

Open-File Report↗
USGS1991

Facies development in the Lower Freeport coal bed, west-central Pennsylvania, U.S.A.

The Lower Freeport coal bed in west-central Pennsylvania is interpreted to have formed within a lacustrine-mire environment. Conditions of peat formation, caused by the changing chemical and physical environments, produced five coal facies and two mineral-rich parting facies within the coal bed. The coal bed facies are compositionally unique, having developed under varying conditions, and are manifested by megascopic, petrographic, palynologic and quality characteristics. The initial environment of the Lower Freeport peat resulted in a coal facies that is relatively high in ash yield and contains large amounts of lycopod miospores and moderate abundances of cryptotelinite, crypto-gelocollinite, inertinite and tree fern miospores. This initial Lower Freeport peat is interpreted to have been a topogenous body that was low lying, relatively nutrient rich (mesotrophic to eutrophic), and susceptible to ground water and to sediment influx from surface water. The next facies to form was a ubiquitous, clay-rich durain parting which is attributed to a general rise in the water table accompanied by widespread flooding. Following formation of the parting, peat accumulation resumed within an environment that inhibited clastic input. Development of doming in this facies restricted deposition of the upper shale parting to the margins of the mire and allowed low-ash peat to form in the interior of the mire. Because this environment was conducive to preservation of cellular tissue, this coal facies also contains large amounts of crypto-telinite. This facies development is interpreted to have been a transitional phase from topogenous, planar peat formation to slightly domed, oligotrophic (nutrient-poor) peat formation. As domed peat formation continued, fluctuations in the water table enabled oxidation of the peat surface and produced high inertinite concentrations toward the top of the coal bed. Tree ferns became an increasingly important peat contributor in the e upper facies, based on the palynoflora. This floral change is interpreted to have resulted from the peat surface becoming less wet or better drained, a condition that inhibited proliferation of lycopod trees. Accumulation of the peat continued until rising water levels formed a freshwater lake within which clays and silts were deposited. The development of the Lower Freeport peat from a planar mire through transitional phases toward domed peat formation may be an example of the type of peat formation of other upper Middle and Upper Pennsylvanian coal beds.

International Journal of Coal Geology↗