bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phricodothyris in New South Wales
Authors: Campbell K. S. W. 
Published: May 2009

AbstractThe relations of the genera Torynifer Hall and Clarke, Phricodothyris George, and Kitakamithyris Minato are discussed, and the diagnosis of Phricodothyris emended. The phricodothyrid species of New South Wales all bear dental lamellae and a median septum in the pedicle valve. Four new species from three horizons within the Carboniferous are described.
A Note on the Mineralogy and Petrology of the Calciphyres near Nanjangud, Mysore, India
Authors: Subramaniam A. P. 
Published: May 2009

AbstractThe calciphyres and granulites near Nanjangud in Mysore were examined in detail in view of the reported occurrence in them of a remarkable assemblage of rare minerals of the Sanidinite fades. A brief field examination disclosed the absence of Gabbrolimestone contacts previously reported. The calciphyres and calc-granulites occur as layers, lenses and nodules in a group of amphibolites and hornblende granulites. Thin sections of these granulites display cataclastic textures indicative of shearing, and crushing. They are found to be composed of minerals characteristic of high grade marbles, and the absence in them of such minerals as larnite, merwinite and spurrite recorded previously, is consistent with the present field observations.
A Lingula-Bed in the Keuper of Nottinghamshire
Authors: Rose G. N. , Kent P. E. 
Published: May 2009

AbstractNumerous specimens of Lingula tenuissima Bronn have been discovered in the Lower Keuper near Eakring, Notts. Earlier records of fossil bivalves in this formation are recalled and the implications of the present find discussed in relation to conditions of deposition of the Keuper.
The Clinopyroxenes of the Garbh Eilean Sill, Shiant Isles
Authors: Murray R. J. 
Published: May 2009

AbstractTen clinopyroxenes have been investigated chemically and optically. Eight of these were separated from the rocks of the Garbh Eilean sill and two from other rocks relevant to this inquiry into the trend during crystallization of pyroxenes in minor basic intrusions of mildly alkaline and undersaturated type.
A New Species of Carbonicola from near the Base of the Namurian in Ayrshire
Authors: Bennison G. M. 
Published: May 2009

AbstractThe marine Johnstone Shell Bed, an important index horizon in the Limestone Coal Group of the Carboniferous of Scotland, is succeeded in North Ayrshire by a bed containing Lingula squamiformis Phillips, and many small shells here referred to a new species of the genus Carbonicola. This Carbonicola community has been examined in detail, and graphical representation of the great variability has been employed.
Erosional Patterns and Fracture Zones in Peninsular India
Authors: Auden J. B. 
Published: May 2009

AbstractThree areas in peninsular India are described in which the geometric orientation of the drainage pattern has led to the location of a system of parallel crustal fractures. One area is in the Archaean basement of South India. The remainder are located on Deccan basalts. The fractures are not as a rule accompanied by fault displacements, and are regarded as planes of shearing. The shearing in the Deccan basalts cuts across the post-lava dykes, and is considered to coincide with late magmatic mineralization and the break-up of the Gondwana continent in mid-Tertiary times.
The Status of Sillimanite as an Index of Metamorphic Grade in the Kenya Basement System
Authors: Sanders L. D. 
Published: May 2009

AbstractRegional studies using certain minerals as indices of metamprphic grade indicate a coincidence between areas of granitic injection or migmatitization and the distribution of sillimanite. Occurrences of that mineral in knotted bodies or faserkiesel and in pegmatites and aplites within migmatites have, however, sometimes been attributed to late metasomatism rather than to metamorphic conditions. In view of the doubtful value of the mineral as an index of metamorphic grade in these circumstances its distribution in the Kenya Basement System is reviewed and the field relationships between sillimanite-bearing metamorphosed pelitic sediments and faserkiesel migmatites occurring in central Kenya are described.It is concluded that sillimanite in the migmatites is derived from partly assimilated sillimanite gneisses, which are of extensive but inconspicuous distribution in the non-migmatitized Basement System. The regional stability of sillimanite rather than kyanite over a great area suggests that high-grade metamorphic conditions prevalent in Kenya during Basement System times were accompanied by granitization processes culminating in the local formation of replacive granites in which sillimanite relics are preserved.
The Granite—Diorite Complex of the Insch Igneous Mass, Aberdeenshire
Authors: Sadashivaiah M. S. 
Published: May 2009

AbstractA complex of granitic, syenitic, and dioritic rocks forms the western part of the Insch mass. All these rocks appear to be related, but they are later than, and have no direct connection with, the basic rocks forming the bulk of the Insch mass. The granitic and syenitic varieties are fairly uniform, but the dioritic types are variable rocks rich in xenoliths which are apparently derived from basic rocks. It is suggested that the diorites were formed by contamination of the magma producing the granitic and syenitic rocks.
The Hypostome of Encrinurus variolaris and its Relation to the Cephalon
Authors: Temple J. T. 
Published: May 2009

AbstractThe hypostome of a specimen of Encrinurus variolaris (Brongniart) from the Wenlock Limestone (Silurian) is described with particular reference to the intricate shape of the lateral wing. This lies very closely underneath the axial furrow of the cephalon in the region of the anterior pit, but it is unlikely that there was a direct articulation of the wing with the pit or the furrow during life.
Cyrtograptids and Retiolitids from County Tipperary
Authors: Cope R. N. 
Published: May 2009

AbstractCyrtograptus hamatus, first described from Ireland by Baily in 1862, is now described more fully from fresh material which can be assigned to the zone of C. lundgreni. The proximal part of C. lundgreni is also described. Three species of Retiolitids occur with the Cyrtograptids, one of which, Paraplectograptus eiseli Manck, has not previously been recorded in the British Isles.
The Carboniferous Breccias of Billefjorden, Vestspitsbergen
Authors: McWhae J. R. H. 
Published: May 2009

AbstractFrom an analysis of data concerning five breccias in the Billefjorden area, Central Vestspitsbergen, and from a consideration of explanations previously advanced of other breccias, it is concluded that the main breccias are due to collapse following solution within the underlying beds.
Petrology of Chloritoid and Staurolite Rocks North of Stonehaven, Kincardineshire
Authors: Williamson Douglas H. 
Published: May 2009

AbstractIn the pelitic rocks of this classical section it appears that, chemically, a Fe2O3: Al2O3 ratio of about 0·40 is critical for the formation of chloritoid or staurolite. With this ratio both minerals are possible, but if the value exceeds a figure somewhere between 0·47 and 0·55 staurolite cannot form, a reddish-brown biotite appearing instead. Physically, a certain minimum temperature is necessary before staurolite can appear and below this chloritoid is the equilibrium phase.
Interpretation of the Gravity Field of the Eastern Alps
Authors: Bott M. H. P. 
Published: May 2009

AbstractIt is demonstrated that a deficient mass reaching within 10 km. of the surface is responsible for the central belt of negative gravity anomalies in the Eastern Alps. Hypotheses for explanation of the deficient mass are discussed and it is concluded that the presence of unexposed granite in addition to crustal downwarp is the most satisfactory of these. The position of part of the mass deficiency is irreconcilable with existing isostatic hypotheses and an alternative hypothesis is proposed. The development of the granite mass deficiency is briefly discussed.
Quartzite Xenoliths from the Ballachulish Granodiorite
Authors: Muir I. D. 
Published: May 2009

AbstractSmall quartzite xenoliths scattered throughout the granodiorite are mantled by broad mafic coronas, the inner part of which is composed largely of augite and the outer part mainly of hornblende. The formation of the coronas is examined and some general features of magmatic reaction with quartzite inclusions are discussed.
Welded Tuffs in the Borrowdale Volcanic Series, English Lake District, with a Note on Similar Rocks in Wales
Authors: Oliver R. L. 
Published: May 2009

AbstractCompact “streaky” rocks, from the Borrowdale Volcanic Series, English Lake District, are diagnosed in part as welded tuffs. Original glass is completely replaced, but similarity to welded tuffs elsewhere is shown by the dacitic-rhyodacitic composition, lack of bedding, and development of columnar jointing. The deposition of welded tuffs, as nuée ardentes, or incandescent tuff flows, is discussed.
The Oligocene-Miocene Boundary on both sides of the Atlantic
Authors: Drooger C. W. 
Published: May 2009

AbstractThe sequence of Miogypsina species in the type region of the Aquitanian-Burdigalian offers a good basis for correlation. Early Aquitanian corresponds to the range of M. gunteri, early Burdigalian to those of M. irregularis and M. burdigalensis, early Vindobonian to that of M. cushmani. In the western Mediterranean area application of this sequence is considered justifiable. Comparison with the similar sequence in America shows a much older occurrence of equivalent species in the western hemisphere than in Europe. A correction of the American time scale is considered premature when made on the Miogypsinidae alone.
Tectonic Facies, Orientation, Sequence, Style, and Date
Authors: Harland W. B. 
Published: May 2009

AbstractSome essential features of the general tectonic description of a region are outlined under the above heads. Tectonic style is the product of facies and orientation in their distinctive sequence, and is assumed to be independent of date. A type of tectonic sequence is outlined from Ny Friesland, Spitsbergen, with a distinct late stage elongation along the fold axes.
The Origin of Garnets in the Borrowdale Volcanic Series and Associated Rocks, English Lake District
Authors: Oliver R. L. 
Published: May 2009

AbstractAlmandine-rich garnets occur as euhedral crystals in extrusive and intrusive rocks which range in composition from 59 per cent, to 70 per cent. SiO2. Eight complete garnet analyses (major and trace elements) indicate a small variation in composition which, together with corresponding variation of physical properties, appear to correlate with the mineralogical composition of the containing rock. Field, microscopic and chemical evidence suggests, on balance, that the garnets are pyrogenetic. Magmatic conditions suitable for the crystallisation of almandine-rich garnet are discussed.
The Olivines of a Differentiated Teschenite Sill Near Gunnedah, New South Wales
Authors: Wilkinson J. F. G. 
Published: May 2009

AbstractData is presented on textural variation, optical properties, and resultant compositions of the olivines from a differentiated teschenite sill. The range in olivine composition is from Fa21 to Fa,60. Both the individual crystals and successive crops of crystals become more fayalitic with progressive differentiation.
Pretoria Series Formations Near Kanye in the Bechuanaland Protectorate
Authors: Cullen D. J. 
Published: May 2009

AbstractAt two localities near Kanye, in the south-eastern Bechuanaland Protectorate, formations previously assigned to the Waterberg System are now correlated with the Pretoria Series of the Transvaal System. In addition to modifying the palæogeography of the Transvaal period, this correlation may also help to clarify the stratigraphical position of the Matsap Series of the Cape Province.
Slope Form and Erosion Surfaces in Uganda
Authors: Pallister J. W. 
Published: May 2009

AbstractA preliminary analysis of slope forms in Buganda has indicated an erosional cycle characterized by both parallel scarp retreat and summit lowering, of which the latter process predominates in the later stages of the cycle. The recognition of characteristic stages in the erosional development of the landscape may provide a means of distinguishing a warped erosion surface occurring at differing altitudes from the products of separate erosion cycles.
A Volcanic Vent in the Bogside Mines, Fife
Authors: Howel Francis E. 
Published: May 2009

AbstractMines near Culross, in Fife, have traversed a vent of Upper Limestone Group (Namurian) age at levels estimated to be 150 to 250 feet below the contemporary surface. The vent-filling comprises a central basaltic tuff, and a marginal lithic tuff derived entirely from the Carboniferous sedimentary rocks. A sill-like body of lithic tuff has been intruded beyond the vent margins. In sediments outside the vent post-volcanic subsidence has generated small faults; these become flat-lying or undulating where they traverse mudstones and siltstones that are inferred to have been incompletely indurated at the time of the subsidence. The volcanic and post-volcanic processes are discussed in the light of Cloos' interpretation of Swabian volcanism.
The Term Eucrite
Authors: Le Bas M. J. 
Published: May 2009

AbstractAn account is given of the history of the term “eucrite”. It is shown to be very varied and hence has been a source of confusion to authors wishing to employ the word with precision, and to readers trying to understand its exact meaning. Because of the lack of agreement over the interpretation of this word, the author proposes that its use should be discontinued and the term “gabbro” utilized in its place.
The Significance of the Hydrothermal Stage in the Formation of Igneous Rocks
Authors: Lehmann E. 
Published: May 2009

AbstractA group of eruptive rocks (weilburgites), widespread in the Lahn-region, is discussed in respect to its genesis. Their close relation to the keratophyres suggests a later mobilization of the keratophyric magma through the volatiles originating from the ascending diabasic magma (allopegmagenesis). In accordance with the character of the weilburgitic magma its ascent was accomplished by adaptation to the orogenic process (gradational ascent).Conditions of this kind might influence the magmatic evolution in several respects. They are intimately related to geological conditions. To them are referred the favouring of allopegmagenetic or even allomagmagenic rocks in Palaeozoic time, the possible difference in age between the beginning of ascent and the emplacement, the lack of correspondence in composition of some rocks with the composition of the originating magma. Thus, the question arises as to how far correlations may exist generally between the mode of magmatic evolution in space and time, the composition of the rocks and the geological age.
Lineation and its relation to sub-crustal Convection Currents
Authors: Anderson E. M. 
Published: May 2009

AbstractA possible cause of the lineation developed in the Scottish Highlands and elsewhere may consist in the presence of sub-crustal convection currents. While it is recognized that these are, to some extent, conjectural, the probable results of the conjecture are compared with the directions of lineation, in areas where this structure has been investigated.
A Quartz Vein System in the Moine Series near Melness, A'Mhoine, North Sutherland, and its Tectonic Significance
Authors: Wilson Gilbert 
Published: May 2009

AbstractKinematic analysis of tension gashes in an exposure of the Moine Series indicates that the fractures resulted from a tectonic movement directed from north to south, unrelated to that responsible for the nearby Caledonian Moine Thrust.
Malvern Tectonics—A Contribution
Authors: Blyth F. G. H. 
Published: May 2009

ABSTRACTThe Malvern ridge consists of a series of Pre-Cambrian fault-blocks, which have been thrust upwards into their present positions through an overlying cover of Cambrian, Silurian, and Lower Old Red Sandstone sediments. The formation of the narrow. localized belt of folds which lie immediately to the west of the Malverns is the result of the displacement of the Pre-Cambrian basement blocks.
The Origin of the Supposed Tufa Bands in Carboniferous Reef Limestones
Authors: Black W. W. 
Published: May 2009

ABSTRACTThin bands of fibrous calcite occur in the Carboniferous reef limestones of northern England and have been regarded as bands of primary tufa within a marine limestone series. A study of these fibrous bands has been carried out and the results show conclusively that they are in fact secondary recrystallization structures.
Allometric Growth in Dielasma hastata from Treak Cliff, Derbyshire
Authors: Parkinson Donald 
Published: May 2009

ABSTRACTGrowth and variation in a single species from a thin bed at one locality are examined statistically. The different dimensions are shown to be allometrically related both to each other and to the volume of the shell. It is argued that total width is the best measure of age of the individual and it is shown that at a certain width there is a break in the continuity of growth of the length and thickness.
The Ontogeny of the TrilobiteDalmanitina olini
Authors: Temple J. T. 
Published: May 2009

AbstractThe ontogeny ofDalmanitina oliniTemple (Upper Ordovician) is described on the basis of specimens from Scania and North Wales. The development is similar to that ofD. socialis(Barrande), but good preservation has enabled some detailed changes in the cephalon to be followed. The protaspid and early post-protaspid stages bear an anterior pit in each axial furrow opposite the frontal lobe. The protaspid anterior glabellar furrow becomes joined to this pit by an oblique furrow, and forms with the latter a composite oblique furrow which develops into the adult anterior-glabellar furrow. This mode of development is considered probably to be common to all Phacopids: the significance of the anterior pits in this family is discussed. Preliminary observations are made on the growth-rates of various parts of the glabella, and the frontal lobe is found to grow in length (sag.) at a rate approximately equal to that of the rest of the glabella.
A glacial erratic boulder of Shap Granite in South Northumberland
Authors: Johnson G. A. L. 
Published: May 2009

AbstractThe discovery of a glacial erratic boulder of Shap Granite in South Northumberland is recorded. Erratics of this rock have not previously been reported north of the Penrith area. It is suggested that the boulder was carried into Northumberland by ice flowing eastwards over the Tyne Gap.
Outline of Geology of the Dardanelles
Authors: Erguvanli K. 
Published: May 2009

AbstractAn outline of the geology of the Dardanelles is presented. Metasediments, chiefly marbles and schists, are cut by a granite and covered unconformably by Tertiary strata which include both sediments and volcanics. The Dardanelles is considered to be a drowned fault valley and in the south an echelon fault system is described.
The Classification and Evolution of the Superfamily Lichacea (Trilobita)
Authors: Tripp R. P. 
Published: May 2009

AbstractThe superfamily Lichacea is here considered to include two families : the Lichidae, composed of four subfamilies and twenty-four genera, and the Lichakephalidae, comprising only one species. Reed's interpretation of the glabellar and occipital lobes in the Lichidae is considered to be correct; the definition and degree of fusion of these lobes is the main criterion of generic discrimination. Hypostomal features are of assistance in defining subfamilies. The characters of the pygidium are constant in some genera, but unstable in others. The Lichinae and Homolichinae, stratigraphically the oldest subfamilies of the Lichidae, are chiefly European in occurrence during the Ordovician period. The Tetralichinae and the Ceratarginae occur earlier in North America than in Europe. Lichakephalus occurs in Lower Tremadoc beds of Bavaria.
A Palaeomagnetic Investigation of the Lundy Dyke Swarm
Authors: Blundell D. J. 
Published: May 2009

AbstractThe directions of the natural remanent magnetization of samples collected from dykes on Lundy have been measured and related to those of Tertiary lava flows in Northern Britain. Evidence is given suggesting that the dykes are Tertiary and pre-Upper Oligocene in age, and that the geomagnetic field was reversed at the time of their intrusion.
A Palaeontological Link between the Midgeholme Outlier, Cumberland, and the Northumberland and Durham Coalfield
Authors: Hopkins W. , Bennison G. M. 
Published: May 2009

AbstractA prominent shell bed from the Middle Coal Measures of the Midgeholme Coalfield, Cumberland, is here recorded for the first time. The fauna, consisting of non-marine lamellibranchs is listed and briefly described. It establishes that the horizon of the Cannel Seam at which the shell bed occurs is within the C. pseudorobusta Sub-zone of the upper part of the C. communis Zone.
Wave Action in Shore Platform Formation
Authors: Edwards A. B. 
Published: May 2009

AbstractErosion of headlands along the southern coast of Victoria results chiefly from the attack of storm waves, and is concentrated above a defined level, marked by certain level shore platforms, whose surfaces are at about high tide level. These platforms are initiated and maintained by storm wave erosion. Their surfaces undergo planation and lowering, chiefly by the scouring action of waves of translation, but increasingly by water-layer weathering as the platforms age and widen.
Note on the Tectonic Style of the Ord Ban Quartzites, Mid-Strathspey
Authors: McIntyre Donald B. 
Published: May 2009

AbstractStudy of profiles, perpendicular to the fold-axes, shows that the folding is disharmonic. Nearly every s−surface is one of décollement. In some exposures the quartzites are reduplicated by superposed recumbent-folds without infolds of other material. The contacts are tectonic and not stratigraphic. Incipient boudinage is frequent, and nearly all surfaces show well-developed b−lineation.
A Xenolithic Sill at Tallabrista, Co. Donegal, Ireland
Authors: Gindy Amin 
Published: May 2009

AbstractAn epidiorite sill emplaced in quartzites becomes charged with xenoliths of quartzite and of an amphibole-rich rock possibly derived from underlying limestone horizons. The matrix of the xenolith-rich part of the sill is studied with large hornblende-biotite “crystals” that may represent small limestone xenoliths that have been basified and homogenized.
Atlantic Gulfs, Estuaries, and Cliffs
Authors: Cotton C. A. 
Published: May 2009

AbstractThe morvan theory with slight modification fits the structure of the coasts of south-western Britain better than the fault theory of Atlantic coasts advanced by Suess.The English Channel and St. George's Channel have been long in existence, and are more probably of tectonic than erosional origin.Erosional deepening of the valleys which were drowned by the Flandrian transgression to become estuaries must have taken place almost entirely in glacial ages when the level of the ocean has been low. The tempo of coastal erosion, both subaerial and marine, has been rather slow, however, owing to the great width of the continental shelf. Thus shoreline details survive from an interglacial age.In regions with a narrower continental shelf, deepening and also extensive enlargement of valleys across coastal lands have taken place in each glacial age of low ocean level, and interglacial aggradations have determined terrace levels at consistent heights in the inland valleys of large rivers, as exemplified in Portugal.The cliffs of Cornwall and Wales show traces of two cycles or marine retrogradation separated by a withdrawal of the sea. Thus the “bevel”, or “coastal slope” above modem cliffs can be accounted for as an ancient sea-cliff graded subaerially during the period of low ocean level.