bluuebunny/crossref_metadata_2025_split huggingface dataset:
Archaean Palaeogeography of Eastern and Northern Singhbhum, Eastern India
Authors: Naha Kshitindramohan , Ghosh Subir Kumar 
Published: May 2009

AbstractGeological studies in eastern Singhbhum and critical analysis of Dunn's published work in surrounding regions suggest that during the Archaean times a volcanic geanticlinal arc, now represented by the Dalma lavas, tuffs and agglomerates extended roughly east–west for more than 150 miles. The geosynclinal trough in the southern, concave side of the arc was filled with argillaceous sediments, thin subgraywackes and orthoquartzites derived from a land mass to the south. The trough in the northern, convex side of the arc was filled with a huge thickness of argillaceous sediments associated with graywackes, siliceous limestones, sandstones and pre-orogenic ultra-basic and basic intrusives. Both the troughs near their border with the volcanic arc were filled with pyroclastic materials.During orogenic movements two anticlinoria were formed in the supracrustal sediments above the two troughs separated by a syncline above the geanticline, with a granulite-migmatite core in the heart of the outer geosyncline.
Reversed Graded Beds from the Dalradian of Inishowen, Co. Donegal
Authors: Knill J. L. , Knill D. C. 
Published: May 2009

AbstractA sequence of reversed graded beds occurs in a group of flaggy rocks intercalated within the Upper Dalradian grits of Inishowen. Usually these beds have a thickness between ½ inch and 2 inches, and are characterized by a laminated, argillaceous base which grades up into a fine-grained, arenaceous upper member.
Modal Variation and the Form of the Beinn an Dubhaich Granite, Skye
Authors: Whitten E. H. Timothy 
Published: May 2009

AbstractRegional variations in modal analyses of the Chandos Lake pluton (Ontario) and the Beinn an Dubhaich granite are compared. Trend surface analysis maps for the latter area show a southwest “grain” parallel to the axis about which King (1960) suggested the sheet of granite is folded. The modal data thus appear to confirm King's hypothesis, and to indicate a more mafic base and increase in quartz content upwards through the sheet. The value to petrogenesis of quantitative variation studies of rock masses is briefly discussed.
Intrusions of Gabbro and Granophyre in the Snaefellsnaes, Western Iceland
Authors: Upton B. G. J. , Wright J. B. 
Published: May 2009

AbstractTwo adjacent areas of intrusive plutonic rocks, occurring in western Iceland are briefly discussed. These intrusions are of gabbros and granophyres, believed to be of Tertiary age, of types closely comparable to those of S.E. Iceland.
Replacement Veins in the Dahomeyan of Ghana
Authors: Burke Kevin 
Published: May 2009

AbstractA basic gneiss in Ghana is traversed by light veins which are considered to have originated by replacement because gneissic mineral banding persists through them. Veins make up to 10 per cent of the rock over hundreds of square miles. It appears that a very large amount of material has been transported through the basic rocks without destroying their gneissic structure.
An Olivine-bearing Hornfels from South-Eastern Queensland
Authors: Phillips E. R. 
Published: May 2009

AbstractContact metamorphism by a gabbro of an unusual slightly metamorphosed argillite with comparatively high magnesia and total iron has produced an olivine-bearing hornfels. The sediment is of such a chemical composition that an almost isochemical transformation is considered to have taken place. Only Mg shows any significant change from the sediment to the hornfels.
The Amphibolite of Doir'a'Chatha (Durcha), Sutherland
Authors: Francis G. H. 
Published: May 2009

AbstractThe amphibolite at Durcha passes from a dark, hornblende-rich rock, through every gradation of delicate striping and banding by quartzo-feldspathic material out into psammitic Moine schist, within a few metres. Irregular cross-cutting bands of quartz and feldspar which seem to “ feed ” the delicate stripes can be seen and there are intergrown mixtures of the dark and light components which recall appinites. Chemical and other evidence suggests that the dark rock is a concordant thpleiitic dolerite sill, whilst the macroscopic and microscopic evidence from the pale bands suggests that they are metasomatic in origin and connected with the widespread permeative alkali-injection of the Moine Schists. They seem to have been introduced into the sill along closely-spaced foliation planes parallel with those in the adjacent sediments and with the original contacts of the sill.
The Lower Middle Hecla Hoek Rocks of Ny Friesland, Spitsbergen
Authors: Wilson C. B. 
Published: May 2009

AbstractThis paper gives details of part of the Hecla Hoek Succession already outlined (Harland and Wilson, 1956). Field work in 1956 and 1957 in general confirmed the succession, and this account includes the results of the later work. A large-scale repetition of a sedimentary cycle is demonstrated, and the relationship with equivalent rocks in Nordaustlandet is discussed.
The Ages of the Hippopotamus and Elephas maximus Fossils in the Gem Sand of Ceylon
Authors: Deraniyagala P. E. P. 
Published: May 2009

AbstractThe extinct Ratnapura fauna of Ceylon is a radiation from the Indian Shivalik. In it occur a hexaprotodont hippopotamus and a race of Elephas maximus which is the most recent member of the Proboscidea. Since such an association is unknown elsewhere, it has given rise to many explanatory theories. A uranium test of associated fossils of both animals now establishes that this has resulted from redeposition and that the animals were not contemporaneous. This makes less vague the hitherto conjectural views regarding the earth movements, and the ages of the gem deposits and of the early human lithic artefacts in them.
Lineations in Three Artificial Tectonites
Authors: Williamson W. O. 
Published: May 2009

AbstractDeformation of plastic kaolinite-illite clay caused alignment of authigenic prisms of rutile and tourmaline on surfaces produced by parallelism of the basal pinacoids of the clay-minerals. An a–lineation appeared in the outer layers of an extruded cylinder but a b–lineation in those of a cylinder formed by rolling. A Wineation occurred at the periphery of a circular disc made by spreading. Localized tensional failures, cognate with ac joints, accompanied the b–lineations which were in directions of elongation. The orienting movements were thought to occur in the water-films separating the clay-flakes, but the mechanisms which produce a– and b–lineations are presumably identical. Thus it can be argued that the a–lineation also follows a direction of elongation.
Additions to the British Eocene Brachiopod Fauna
Authors: Elliott G. F. 
Published: May 2009

AbstractTwo species of Argyrotheca new to this country are recorded from the type Bracklesham Beds, and a full description given of the associated Terebratulina edwardsi, previously known from immature specimens only. The British Eocene brachiopods are listed, and the ecological significance of their rarity and distribution briefly discussed.
The Old Red Sandstone Lavas of the Western Sidlaw Hills, Perthshire
Authors: Harry W. T. 
Published: May 2009

AbstractThe Old Red Sandstone lavas of the Perthshire Sidlaws are basalts with some andesite-basalts, andesites, and rare trachyandesite. The basalts comprise chiefly olivine-bearing flows that include feldspar-phyric and aphyric varieties; olivine-free basalts with two pyroxenes are of restricted distribution.The significance of augite textures and their relationship to augite content in the basalts is discussed.The lava pile is apparently composed of interdigitating lenticular flows that vary from a few feet up to about 80 feet in thickness.Unlike most other Scottish Old Red Sandstone lava suites the Sidlaw suite is fairly fresh and, like the Eastern Forfarshire lavas, it is relatively basic.
The Development of a Diplograptid from the Platteville Limestone
Authors: Walker Margaret 
Published: May 2009

AbstractThis paper describes the development from the initial prosicula of the rhabdosome of Diplograptus cf. (Amplexograptus) maxwelli Decker. Points of comparison with other diplograptid astogenies are noted. Evidence about the structure of the interthecal septum is brought forward and so stages in the formation of one thecal segment can be defined. Mention is made of some abnormal specimens.
The Diorites and Associated Rocks of the Glen Tilt Complex
Authors: Deer W. A. 
Published: May 2009

AbstractThe diorites and Sron a' Chro' granite of the Glen Tilt complex enclose hornblende-schist xenoliths derived from the Dalradian epidiorites of the country rock. Small hornblendite xeoliths are found in the complex but are restricted to the diorite outcrop. Porphyroblastic hornblende is developed within the schist xenoliths and reaction zones rich in hornblende are formed around the xenoliths. The mineralogical and textural characteristics of these reaction products suggest that the typical two-hornblende generation appinites of the complex represent modified hornblende schist. A similar origin for the quartz-orthoclase-appinite of the complex is rejected and their development from hornblendite is indicated.
Magnetometric Mapping for Haematite in South Wales
Authors: Blundell C. R. K. 
Published: May 2009

AbstractIn the search for large deposits of haematite and other feebly magnetic minerals, it is suggested that mapping the magnetic residuals may be of greater value than mere linear traverses. Not only is the method more suitable for exploring virgin areas, but it also affords a means of differentiating between the effects of large deeply buried masses and small objects at shallow depths. At the same time, the graphical expression of the results on the map becomes more easily intelligible.The application of the method to known haematite ore-bodies in South Wales has yielded striking results and the extension of the survey into an unexplored area indicates the possibility of proving at least one further large haematite deposit.
The Nephelinite of Etinde, Cameroons, West Africa
Authors: Tilley C. E. 
Published: May 2009

AbstractRe-examination of the nephelinites of Etinde, Cameroons, carrying a composite structured “nepheline” mineral shows that the feldspathoid is a genuine nepheline, in part exhibiting twinned intergrowths, and not a potassic orthorhombic feldspathoid phase. Analysis indicates a composition with a mol. ratio of 3·6. Comparison is made with other nephelines in contrasted host environments.
The Extent of Glaciation in the Island of St. Kilda
Authors: Wager L. R. 
Published: May 2009

AbstractMoraines which in one case at least contain striated boulders, show that, at the maximum of Quaternary glaciation, small, thin glaciers developed in the island of St. Kilda at certain favourable places. There is no evidence that the Hebridean ice sheet reached the island and no signs of raised beaches which would indicate recent emergence.
A Local Potassic Modification of the Ballachulish Granodiorite
Authors: Muir I. D. 
Published: May 2009

AbstractThe development of potash-rich pyroxene-bearing rocks around inclusions derived from the Appin limestone is associated with the transfer of magmatic silicon, aluminium, iron, and sodium. Calcium lost to the magma, by combining with further silicon, aluminium, and sodium to form a marginal zone rich in plagioclase, has left the magma enriched in potassium.
On the presence of the Upper Dibunophyllum Zone (D3) near Glynneath, South Wales
Authors: Owen T. R. , Jones D. G. 
Published: May 2009

AbstractBeds near Glynneath previously believed to be of Middle Dibunophyllum Zone (D2) age are claimed to belong to the Upper Dibunophyllum Zone (D3). These beds are described, and the implications of the position of this new locality on the Neath Disturbance are discussed.
The Western Longmyndian Rocks of the Shrewsbury District
Authors: Whitehead T. H. 
Published: May 2009

AbstractEvidence from graded bedding and other sedimentary structures has shown that in the eastern outcrop of the Western Longmyndian rocks of the Shrewsbury area the stratigraphical base lies towards the east. Since in the western outcrop of these rocks the base is believed to lie towards the west, Professor Whittard's suggestion that the Western Longmyndian rocks are folded into a syncline, with the “ Oakswood Group ” representing a repetition of the “ Bayston Group ”, is accepted. The form and age of the fold are briefly discussed.
The Occurrence and Significance of Pre-Cambrian Algal Forms at Kabwer Hill, Bukoba District, Tanganyika, and in Singo, Uganda
Authors: Pallister J. W. 
Published: May 2009

AbstractStromatolites found in Karagwe-Ankolean rocks on the Tanganyika-Uganda border occur in siliceous beds associated with cherty and ferruginous breccia without trace of calcareous material. Somewhat similar conditions prevail in beds of the Singo Series of Uganda from which Collenia-type structures have been recorded. Little stratigraphical value can be ascribed to the structures, but they are significant in pointing to the replacement character of some fine-grained siliceous beds which may explain the scarcity of limestone in the Pre-Cambrian sequence of Uganda.
The Structure of the Plastron of the Echinoid Somaliaster Hawkins
Authors: Joysey Kenneth A. 
Published: May 2009

AbstractPrevious descriptions of the plastron of Somaliaster Hawkins have been conflicting and, in consequence, there has been some doubt regarding the systematic position of this genus. The type-material has been re-examined and the plastron found to be meridosternous. Somaliaster is here referred to the family Stenonasteridae, where it has close affinities with Iraniaster Cotteau and Gauthier.
The Occurrence of Orthoclase and Microcline in the Granitic Gneisses of the Carn Chuinneag-Inchbae Complex, E. Ross-shire
Authors: Harker R. I. 
Published: May 2009

AbstractOptical examination of the potash feldspars in the granitic gneisses of the Carn Chuinneag-Inchbae complex suggests that both ortho-clase and microcline occur together—not infrequently in the same crystal. Optic axial and extinction angles, intermediate in value between those characteristic of the two polymorphs, have been recorded and plotted graphically. X-ray powder diffraction patterns confirm that both orthoclase and microcline are present together in these rocks. It is believed that most of the microcline developed from orthoclase during the regional metamorphism of the area, which permitted recrystallization at a lower temperature than that at which the orthoclase was formed.
The Form of the Eastern End of the Insch Igneous Mass, Aberdeenshire
Authors: Sadashivaiah M. S. 
Published: May 2009

AbstractPeridotite, troctolite, and olivine-gabbro are exposed in the Bourtie area at the eastern end of the Insch igneous mass. The distribution of outcrops suggests that the rocks are disposed in bands running north and south and a smaller-scale north-south banding can be seen in some exposures. The earlier view that the ultrabasic rocks form an east-west lens on the floor of a northerly-dipping gabbro sheet is therefore abandoned and both the northern and southern contacts are believed to be part of the roof of the igneous body.
Idosocrinus gen. nov. and other Crinoids from Thornton Burn, East Lothian
Authors: Wright James 
Published: May 2009

AbstractThe new genus Idosocrinus is proposed for a remarkable type of crinoid occurring in the Thornton Burn section of the Calciferous Sandstone Series (Lower Carboniferous) of East Lothian, and two species are recognized. In general habitus the new genus resembles Phanocrinus Kirk, but differs in the character of the left and right posterior primibrachs, which extend outward from the cup in the form of strongly developed spines. Two new specimens of Anemetocrinus wilsoni Wright are also figured.
A New Ampthill Clay Fauna from Knapwell, Cambridgeshire
Authors: Hancock J. M. 
Published: May 2009

AbstractA new ammonite assemblage from the Ampthill Clay is recorded. Its correlation with the Trigonia clavellata beds of Dorset indicates that these condensed beds are represented by two distinct horizons in the Ampthill Clay—the Boxworth Rock below and the Knapwell Ditch horizon above.
Petrofabric Analysis of Marbles from Mid-Strathspey and Strathavon
Authors: McIntyre Donald B. , Turner Francis J. 
Published: May 2009

AbstractPetrofabric analyses of marble specimens from three widely separated localities in Mid-Strathspey and Strathavon are recorded. Preferred orientation of [0001] in the constituent grains of calcite conforms to a B-tectonite pattern, the symmetry axis (B) of which coincides with the b axis of the megascopic fabric (lineation and fold axis) at each locality. Development of {011¯2} lamellae in calcite grains is attributed to late minor compression, the direction of which is more or less horizontal and trends between N.E.–S.W. and E.N.E.–W.S.W.
The Miocene/Oligocene Boundary and the Use of the Term Aquitanian
Authors: Eames F. E. 
Published: May 2009

AbstractIt is considered that some fossils, e.g. Orbulina and Miogypsina, are good indicators that beds containing them are of post-Oligocene age, and that the ages of some beds in certain parts of the world require reconsideration; mention is made of successions in Morocco, Venezuela, and Peru. It is recommended that the use of the term “Aquitanian” be restricted to beds of basal Miocene age.
Breconian: a Stage Name of the Old Red Sandstone
Authors: Croft W. N. 
Published: May 2009

AbstractThe Breconian stage of the Anglo-Welsh Old Red Sandstone is defined. The Breconian follows the Dittonian and precedes the Farlovian. In Breconshire, the Breconian comprises the Senni Beds and the overlying Brownstones. The Senni Beds have yielded a fauna and flora of Siegenian-Emsian age; the Brownstones are apparently unfossiliferous.
Fausto de Elhuyar (1755–1833), A Spanish Mining Geologist
Authors: Eyles Joan M. 
Published: May 2009

AbstractElhuyar, born in Spain in 1755, received a thorough training in mining geology at several of the leading European mining schools. He was appointed to an important post in New Spain (Mexico), where he arrived in 1788. There he devoted himself to reorganizing the administration of the mining industry and then to founding a School of Mines in Mexico City. This was opened in 1792, and in 1811 moved into the magnificent new building known as El Palacio de Minería, which now houses the Engineering School of the University. When an independent government was set up in Mexico in 1821, Elhuyar returned to Spain, where he continued to work for the government as a mining consultant. He prepared a report on the Rio Tinto mines and was responsible for the planning of the School of Mining Engineering in Madrid.
Shear-Folding in the Mylor Slates, near Porthleven, Cornwall
Authors: Stone M. , Lambert J. L. M. 
Published: May 2009

AbstractRecumbent shear folds and their related structures in the Mylor Slates are briefly described. It is concluded that folding has been produced by subhorizontal shearing stresses acting in a northwesterly or south-easterly direction.
Some “Uniserial” Membraniporine Polyzoan Genera and a New American Albian Species
Authors: Thomas H. Dighton , Larwood G. P. 
Published: May 2009

AbstractHerpetopora Lang is considered to be a junior synonym of Pyripora d'Orbigny, from which Rhammatopora Lang is distinguished by possessing apertural spines. A new species of Pyripora is described from the Albian of Texas.
The Horizon of the Tillery Vein in Monmouthshire
Authors: Sullivan H. J. , Moore L. R. 
Published: May 2009

AbstractThe discovery of a hitherto unrecorded non-marine lamellibranch fauna from the Tillery Vein of Monmouthshire indicates that this coal represents a horizon at, or near, the junction of the Phillipsii and Tenuis Zones. The characteristics of the seam in a small portion of the North Crop of the South Wales Coalfield are described in an attempt to account for the limited occurrence of these shells.
Contact Phenomena from N.W. Jersey, C.I
Authors: Henson F. A. 
Published: May 2009

AbstractThe field relationships between the Armorican granite of North-West Jersey and the Precambrian sediments in the Le Pulec and L'Etacq areas are described together with the petrography of the contact rocks. Trace-element determinations on rocks from two traverses across contacts in the area, and upon control specimens of granite and sediments supplement the petrography. The mechanism of granite emplacement in this area is discussed.
On certain geological similarities between North-East Shetland and the Jotunheim area of Norway
Authors: Flinn Derek 
Published: May 2009

AbstractIn a recent account of the geology of North-east Shetland (Flinn, 1958, Quart. Jour. Geol. Soc.) two nappes of crystalline rocks lying one above the other on a base of meta-sedimentary rocks were recognised. Comparison with the Norwegian geological literature followed by field investigations in Norway has shown many similarities with the Jotunheim area of Norway. In both areas two relatively rigid nappes were thrust one after the other over the surface of the earth to their present positions. In both areas the lower of the two nappes was emplaced first and was subjected to erosion giving rise to sediments which were deposited on the nappes (Phyllite Group of Shetland and the Valdres Sparagmites of Norway). These sedimentary groups had a similar history of formation, deformation, and metamorphism, but differed somewhat in materials because the source rocks were different, although several strikingly similar rock types are present as pebbles in both areas. The remains of the first nappe and the newly deposited sediments were overrun by the second nappe in both areas. The emplacement of these nappes gave rise to considerable deformation and metamorphism in the underlying rocks. If the metamorphic rocks of Shetland are of Caledonian age, as seems likely, then it is possible that the Valdres Sparagmites and the Phyllite Group are stratigraphically equivalent: they are certainly tectonically equivalent.
Cyclic Sedimentation of the Rough Rock (Millstone Grit) as illustrated by a section near Eakring, Nottinghamshire
Authors: Bond K. W. 
Published: May 2009

AbstractThe section described is a well section, 20 miles from the nearest Millstone Grit outcrop. Attention is drawn to the rhythmic sedimentation resulting from the intermittent subsidence that was occurring at the time.
Cyclic Resection of Headlands by Marine Erosion
Authors: Cotton C. A. 
Published: May 2009

ABSTRACTThough good examples of plunging cliffs surviving as such are now rare, this form of shoreline was probably commoner in the initial stages of the current (postglacial) cycle of marine erosion. Most cliffs now bordering the sea, whether developed from initially plunging cliffs or not, have already receded some distance from the initial shoreline.As plunging cliffs may, because of reflection of waves from them, enjoy some immunity from direct frontal attack, the headlands which they truncate may be more vulnerable to marine erosion on the flanks, where the slopes partially submerged by shift of ocean level are less steep. Flank attack may lead to resection of the headland in such a way that eventually it will again end distally in a straight line of cliff; but at an intermediate stage of this resection cycle the terminations of headlands are characteristically scalloped, while at a penultimate stage of resection the salient of submaturity may be reduced to a row of stacks, the “needles” stage