bluuebunny/crossref_metadata_2025_split huggingface dataset:
Galilean invariance and stabilized methods for compressible flows
Authors: Scovazzi G. 
Published: February 2007

AbstractIn a recent work (Comput. Methods Appl. Mech. Eng. 2007; 196(4–6):966–978), it was observed that lack of Galilean invariance led to catastrophic instabilities when stabilized methods were used in Lagrangian shock hydrodynamics computations. By means of an arbitrary Lagrangian–Eulerian (ALE) formulation, Galilean invariant SUPG operators were consistently derived in (Comput. Methods Appl. Mech. Eng. 2007; 196(4–6):1108–1132), and their Lagrangian and Eulerian limits were compared to the most commonly used stabilized formulations. In the particular case of Eulerian meshes, it was shown that most of the SUPG operators designed to date for compressible flow computations are not invariant. However, due to the significant overhead of algebraic manipulations, the use in (Comput. Methods Appl. Mech. Eng. 2007; 196(4–6):1108–1132) of the referential form of the ALE equations made the presentation of the main ideas quite involved. The present paper addresses this particular issue, since the invariance analysis is presented with the aid of the intuitive current configuration reference frame, more familiar to computational fluid dynamicists. Copyright © 2007 John Wiley & Sons, Ltd.
A Multi‐Scale Dynamic Mechanistic Model for the Transient Analysis of PEFCs
Authors: Franco A. A. , Schott P. , Jallut C. , Maschke B. 
Published: February 2007

AbstractElectrochemical impedance spectroscopy is an experimental technique widely used for the transient analysis of PEFCs. Experimental results are usually analyzed using equivalent circuit models, which have to be fitted to each operation point and do not offer direct access to the internal physical parameters of the electrodes.In this paper, a multiscale mechanistic Membrane‐Electrode Assembly model is proposed, based on irreversible thermodynamics and electrodynamics, and dependent on the internal physical parameters, such as the effective catalyst surface, the electrical permittivity of the materials, the reaction kinetics, and the diffusion coefficients of the reactant species.This model results from the coupling of a microscale transport phenomena description through the electrode and the electrolyte thickness, a spatially distributed microscale model of the reactant diffusion through the Nafion® layer covering the Pt/C particles, and a spatially distributed nanoscale description of the Nafion®‐Pt/C interface. This interfacial model is based on an internal description of the double layer dynamics, coupling the transport phenomena in the diffuse layer with the electrochemical reactions and water adsorption in the inner layer.The system dynamics can be simulated and are dependent on the current, the temperature, the reactant pressures, and the Pt/Nafion® loadings on the electrodes. The first simulations carried out are in good qualitative agreement with experimental results, giving access to the contributions of the different phenomena and to the sensitivity of the operating conditions.
The anatomy of a coal seam split, Durham coalfield, Northeast England
Authors: Fielding C. R. 
Published: February 2007

AbstractA pronounced coal seam split, one of many within the Lower Westphalian B (Upper Carboniferous) sequence of the Durham coalfield, northeast England, occurs in the vicinity of the village of Burnhope. This feature involves the division of the combined Main/Fivequarter coal into its two component parts, which become separated by up to 8 m of clastic sedimentary rocks over a horizontal distance of 150 m.Three‐dimensional outcrop data from an opencast (surface) coal mine straddling the split, supported by extensive subsurface information, have allowed detailed study of the seam split geometry, in addition to that of three overlying coal seams and intervening clastic facies.The study suggests that deposition of the interval as a whole, including the split, was strongly influenced by compaction‐controlled subsidence, and not by either contemporary fault movements or channel sedimentation.A substantially greater aggregate thickness of coal is preserved over the five seam interval where the Main/Fivequarter is unsplit than where split. This relationship is consistent with the coal depositional model proposed by Fielding (1984a), which proposed that thick coals in the Durham area are located adjacent to, but not within, coal seam splits. It further implies that attractive sites for future opencast development in the area may be predicted from a regional knowledge of coal seam splits.
Gulf of Mexico Basin: Newest coal province
Authors: Groat C. C. 
Published: February 2007

AbstractPost World War II oil came to replace coal as the dominant energy source in the U.S.A. Recently, coal in the form of lignite has again become a significant energy resource in the Gulf Coast region, where it occurs in Eocene and Oligocene rocks. Efficient exploitation requires a proper understanding of the facies in which it occurs. Studies of surface outcrops are providing the basis for predicting the nature of the reserves at depth.
The Northern Charlotte belt North Carolina and South Carolina: A deformed composite batholith
Authors: Wilson Frederick A. , Jones William J. 
Published: February 2007

AbstractThe Charlotte belt in North Carolina and South Carolina, U.S.A. is characterized by numerous plutons with granitic to gabbroic composition that have intruded gneiss, schist, metavolcanic rocks, and metamorphosed mafic complexes (basalt, gabbro, and ultramafic rocks). The exposed rock constitutes a composite batholith which contains three superunits: (1) the Old Plutonic (metaquartz diorite, metagranodiorite, and metagabbro) approximately 550 my old; (2) the Concord‐Salisbury (gabbro and granodiorite) approximately 400 my old; (3) the Landis ('big feldspar') granite approximately 300 my old. Geophysical and geologic studies suggest small bodies of granodiorite and mafic complexes intruding metavolcanic rocks, schist, and gneiss form the upper level of the batholith; a thick metagabbro sill penetrated by gabbro stocks and underlain by poikilitic gabbro and small bodies of syenite form the middle level; and a complex of metaquartz diorite and metagranodiorite intruded by Landis granites form the lowest level. Outcrop patterns and structural profiles based on gravity suggest the batholith forms an east‐dipping monocline. The bimodal suite of gabbro and granodiorite plutons suggest a tensional tectonic environment ∼ 400 my ago, and negates subduction as the only mode of formation for the batholith.
The Quassaic Group, a Medial to Late Ordovician arenite sequence in the Marlboro Mountains Outlier, mid‐Hudson Valley, New York, U.S.A
Authors: Waines Russell H. 
Published: February 2007

AbstractThe Quassaic Group occurs as an outlier in the north‐south trending Marlboro Syncline which extends 40 km between Kingston and Newburgh in southeastern New York. The group is comprised primarily of 3050 m of late Medial to medial Late Ordovician marine arenites. It is subdivided (oldest to youngest) into five formations: Creek Locks, Rifton, Shaupeneak. Slab Sides, and Chodikee. On the western limb of the syncline the group overlies a minimum of 610 m of the early late Medial Ordovician Bushkill Shale and the bottom three formations grade north and south to Bushkill Shale.Abundance of graded but occasionally conglomeratic beds, common tabular cross‐lamination, much less common trough cross‐lamination, comparative lack of channelling, general lack of shales, and scarcity of fossils indicate that the average depositional environment of the formations was near the base of the slope of a sedimentary apron or delta which lay to the southeast. The environment, however, probably extended from a basin plain, in the marginal Bushkill Shale, through the lower and middle slope and, rarely, to the upper slope. The occasional molasse‐like deposits in the Shaupeneak Formation may indicate local transport of molasse to an upper slope position.The Quassaic Group thus records an initial, local extension of arenites of the lower slope of an apron or delta onto a downwarping basin plain in the Bushkill Trough. This was followed by progressive enlargement and extension of the delta slope with attendant shallowing, culminated by the appearance of molasse‐like sediments. Subsequent deposition involved greater slope extension followed by recession with gradual deepening. These activities were prelude to the Hudson Valley Phase of the Taconian Orogeny which downfolded the Quassaic Group into the Marlboro Syncline during latest Ordovician times.
A section in Linley Brook (Shropshire) showing a previously unrecorded junction between the Ludlow and Přídolí Series
Authors: Bradfield Kim E. S. , Tucker E. V. 
Published: February 2007

AbstractA new contact between the Ludlow and Přídoli Series is described in Linley Brook (Shropshire) previously noted only for its exposure of the Downton Castle Sandstone Formation and the Temeside Shales Formation. The Ludlow Bone Bed and the Downton Bone Bed are recorded and the Upper Whitcliffe and the Downton beds are correlated with a section at Willey.
The age of the Lugar sill and a discussion of the Late‐Carboniferous/Early‐Permian sill complex of S.W. Scotland
Authors: Henderson C. M. B. , Foland K. A. , Gibb F. G. F. 
Published: February 2007

AbstractThe incremental heating 40Ar/39Ar method has been used to date a kaersutite separate from the main theralite‐picrite unit of the Lugar sill. Ar‐release spectra show discordance mainly due to the presence of excess Ar in alteration phases intimately associated with the primary kaersutite. Plateaus in the spectra allow an emplacement age of 288 ± 6 Ma (2γ) to be assigned to the sill. The results are used to discuss the age relations of the alkaline Permo‐Carboniferous sill complex of southwest Scotland. It is concluded that these sills could have been emplaced over a shorter period of time than implied by the available conventional K/Ar data. The classification of the alkaline sills into kylite and teschenite types has little petrogenetic significance.
The outflow of Windermere, Cumbria: A re‐appraisal
Authors: Wilson C. D. V. 
Published: February 2007

AbstractPossible causes for the outflow of Windermere through the Leven valley instead of the Cartmel valley are discussed. An earlier seismic investigation of the problem by Coster and Gerrard (1947) is reviewed and shown to be inconclusive. Further geophysical surveying and mapping demonstrate a rock bar in the Cartmel valley, 3km southeast of Newby Bridge. This barrier is 21m above the present water level in Windermere. Blockage by glacial deposits is disproved and the probable history of the outflow discussed. It is concluded that the outflow from Windermere has used the Leven valley from an early stage.
Depositional environments in the Telychian Stage (Silurian) of the central Oslo region, Norway
Authors: Baarli B. G. 
Published: February 2007

AbstractThe Telychian succession in the central Oslo region was previously interpreted as deposited in a relatively deep, calm environment showing a continuous transgressive development. A new analysis of fossil assemblages shows that sediments in the central districts were deposited at varying water depths in an environment marked by intense infaunal activity in soft substrates. Two small‐scale fluctuations in sea level are attributed to eustasy. The maximum deepening events occurred during the Monograptus turriculatus and Monoclimacis crenulata graptolite zones.Previous depositional models include development of a trough to the north of the Oslo region in early Telychian time, which formed due to isostatic loading caused by an advancing thrust front of the Caledonian Orogeny. Bathymetric analysis shows a deepening in the Ringerike district in the latest Aeronian, which here is interpreted as a distal effect of the loading to the north. The local deepening led to reversal of the epicontinental slope between the northern and western districts and the central districts and the development of an east–west elongate positive area further south. The thrust front acted as a source of siliciclastic material; and when the front halted in mid‐Telychian time the trough was filled in gradually by a prograding coast or delta. The diachronous Vik Formation is viewed as a distal development of this progradation. When the east–west oriented positive area subsided the Vik Formation was deposited in Skien to the south.
Late Ordovician stratigraphy northwest of the Sugarloaf, mid‐Wales — a discussion
Authors: James D. M. D. 
Published: February 2007

AbstractSeveral modifications are proposed to the Ordovician stratigraphy recently proposed by Mackie and Smallwood (1987), based in particular on the recognition of a major Mynydd Trawsnant anticline on the northwest flank of the Tywi structure and on field relationships indicating the Foel Formation directly to overlay the Caradoc black shale succession and directly to underlay the Craig Las Formation. The Clyn Glas Formation is suggested to have accumulated at a slope base rather than a shelf–slope break.
Granitoid rocks and terrane characterization: An example from the northern Appalachian Orogen
Authors: Barr Sandra M. 
Published: February 2007

AbstractGranitoid rocks in the Aspy, Bras d'Or, and Mira terranes of Cape Breton Island in the northern Appalachian Orogen display contrasts in age and petrological characteristics that reflect differences in source rocks and tectonic events in these three terranes. The Aspy Terrane is characterized by a protracted Silurian and Devonian plutonic history, during which granitoid rocks were generated sequentially in volcanic‐arc, post‐arc, collisional, and extensional tectonic settings. In contrast, the Bras d'or and Mira terranes are characterized by Late Precambrian calc‐alkalic I‐type granitoid suites, and only minor Devonian plutonism. Late Precambrian suites in the Bras d'Or Terrane (age ca. 565–555 Ma) are significantly younger than those in the Mira Terrane (age ca. 620 Ma), and the two suites are interpreted to have formed in separate volcanic arcs.
Anorogenic granite evolution in Namibia—a fluid contribution
Authors: Bowden Peter , Kinnaird Judith A. , Diehl Michael , Pirajno Franco 
Published: February 2007

AbstractField observations, petrological interpretations combined with cationic geochemical data and diagrams illustrate the magmatic and postmagmatic events in the Mesozoic anorogenic complexes of northern Namibia. The magmatic lineage of the Damaraland alkaline centres is cationically defined in a modified Q–P diagram (Debon and Le Fort 1988). Major element concentrations for Brandberg and Erongo supported by chemical data from other Damaraland complexes at Cape Cross, Otjihorongo, Messum, Spitzkoppies, and Paresis, have been converted to millications, to delineate a magmatic lineage which follows an alkaline oversaturated trend. Superimposed on this magmatic lineage is textural and geochemical evidence for hydrothermal metasomatic disequilibrium and partial re‐equilibration. Volcanic rocks and their granitic equivalents from the Erongo complex show petrological and geochemical criteria indicating substantial potash and boron metasomatism which has given the Erongo rocks a subalkaline potassic geochemical signature. Similar granite compositional trends are also recorded within the Brandberg massif. However, at Brandberg, there is a later‐stage hydrothermal overprint generating a texturally variable peralkaline granite, with spectacular examples of linear zones of aegirine and arfvedsonite apparently constrained to microfractures in marginal granite sheets. The zones of mineral ‘layering’ can be divided into three repetitive units and traced horizontally along the southwestern margin of the Brandberg massif for a distance of 3 km and vertically for 200–300m. These marginal rocks are cross‐cut by dykes and sheets of brandbergite, a mesocratic fine‐grained peralkaline rock. Fenite veins, described elsewhere from marginal zones of strongly alkaline massifs, are found near the inner brecciated contact zone with the main granitic mass of the Brandberg. These fenite veins are interpreted as fluid‐channel ways along which mass transfer of peralkaline components occurred during the final stages of cooling and consolidation.
A late ordovician/early silurian non‐depositional slope and perched roll‐over basin along the tywi anticline, mid wales
Authors: James D. M. D. 
Published: February 2007

AbstractOrdovician stratigraphy between the Sugarloaf and the Wye valley is summarized with particular attention given to the area northeast of Abergwesyn. New data refine thickness estimates for the Cerriggwynion Formation, the Trembyd Formation (new), and the Cefn Cynllaith Formation (new). The major Bron Rhudd Fault is suggested to have been a synsedimentary down‐to‐basin fault which was later reactivated, folded, and suffered local reversal of throw. Roll‐over into this fault controlled deposition of mass‐flow conglomerates in a perched basin. During the late Ordovician‐early Silurian the axis of the Tywi Anticline underlay a non‐depositional slope which developed by northwest‐directed progradation of a shelf margin, possibly accentuated by flexure over a basement fault zone with contemporaneous basin‐down normal movement. The slope angle cannot be estimated from the geometry of the Ordovician because the contemporaneous throw on the Bron Rhudd Fault cannot be determined, but from the rate of Silurian onlap it was about 5 degrees.
Ice directions in western lleyn and the status of the gwynedd readvance of the last irish sea glacier
Authors: McCarroll Danny 
Published: February 2007

AbstractA ‘Gwynedd readvance’ of the last Irish Sea glacier, terminating on the north coast of the Lleyn peninsula in northwest Wales, has been proposed on the basis of differences in ice flow direction and in drift landforms on either side of the proposed limit. However, detailed drift mapping of western Lleyn reveals erosional and depositional evidence of ice flow direction which are consistent with a single advance and retreat. Differences in drift landforms are explained by the influence of topography on glacier dynamics and sedimentation. There is, therefore, no reason to invoke a ‘Gwynedd readvance’ of the last Irish Sea glacier and the marked climatic deterioration which a substantial readvance of such a large glacier would imply.
A newly‐discovered coal measures marine band in billinge beacon quarry, lancashire, and its stratigraphical significance
Authors: Eagar R. M. C. , Chisholm J. I. , Varker W. J. , Williamson I. A. 
Published: February 2007

AbstractA thin band yielding conodonts and Foraminifera and therefore demonstrably marine, has been found in mudstone lying immediately above the uppermost coal horizon in Billinge Beacon Quarry. The existence of this newly recognized horizon, which is very likely to be the Langley Marine Band at the top of the Lenisulcata Chronozone, much strengthens the correlation of the Billinge Beacon sandstones with the regionally developed Crutchman Sandstone. An alternative correlation of the Billinge Beacon sandstones with the Dyneley Knoll Flags of Burnley, which was recently proposed by F. M. Broadhurst, is not supported by the new evidence, nor by the evidence of boreholes, since it appears that the Dyneley Knoll Flags die out some distance to the north of Billinge.
A non‐glacial origin for the ordovician (middle caradocian) cosquer formation, veryarc'h, crozon peninsula, brittany, France
Authors: Long D. G. F. 
Published: February 2007

AbstractThe presence of a dispersed clast fraction in strata near the base of the Cosquer Formation in west Brittany, does not support a glacial origin for this unit. The upper 25 to 30 m of the underlying Kermeur Formation consists of a prograding sequence of very fine to fine sandstones deposited in a mid to distal current swept shelf setting. This sequence shows signs of slope instability, as do the supposed ‘glacial strata’ which overlie it. The upper two thirds of the Cosquer Formation contain spectacular slump‐breccias. Smaller clasts within the laminated mudrocks at the base of the formation are associated with thin graded and non‐graded sandstone laminae. They show no evidence of active penetration into underlying laminae other than can be explained by compaction. Larger clasts are confined to thicker massive beds, or disrupted units with marked internal contorted lamination. This, along with the abundance of slump features within the sequence suggests lateral emplacement by sediment gravity flows in a distal shelf‐slope setting. Surface textures of sand grains within the formation are related to rock disaggregation along fractures developed during post‐depositional deformation and are not related to glacial processes. Distinctive mineralogically immature, poorly‐sorted aggregate sediment pellets, which have been considered as positive proof of glaciation, are not present.
An endemic brachiopod fauna from the Middle Ordovician of North Wales
Authors: Harper D. A. T. , Brenchley P. J. 
Published: February 2007

AbstractThe brachiopod fauna from the base of the Bryn Siltstone Formation (middle Caradoc), Glyn Ceiriog, north Berwyn Hills, North Wales, consists of Platystrophia elevata sp. nov., Salopia abbreviata sp. nov., Kiaeromena ungula (M'Coy) and unnamed species of Hesperorthis?, Reuschella and Bicuspina. The dominant brachiopod species, Leptaena (Leptagonia) ungula M'Coy, 1851 is revised and its current assignment to the leptaenid genus Kiaeromena confirmed, based on the examination of type and topotype material from the Bryn Siltstone Formation. Kiaeromena spjeldnaesi nom. nov. is proposed to replace the junior homonym K. ungula Spjeldnæs, 1957 for that congeneric species from the upper Caradoc rocks of Ringerike, southern Norway. The fauna as a whole is unusual within the context of the Anglo‐Welsh province and may represent a rare preserved nearshore community.
Diffusive equilibration between minerals during cooling: An analytical extension to Dodson's equation for closure in one dimension
Authors: Powell Roger , White Lee 
Published: February 2007

AbstractContinuing element exchange between minerals during cooling from the metamorphic peak modifies mineral compositions from those existing at the peak. After closure, when the minerals stop changing composition, the compositional relationships hold important information regarding, for example, cooling rates. Whereas the classic result of Dodson (1973) regarding closure provides an important limit, the situation involving element exchange with a slow diffusing mineral equilibrating with a finite faster diffusing mineral is more valuable in considering metamorphic systems. An analytical extension to Dodson's equation for this situation in one dimension is presented here, and some of the consequences of departing from Dodson's limiting case are illustrated.