bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physico‐chemical analysis of paragenesis of minerals: A review
Authors: Marakushev A. A. , Perchuk L. L. , Rast N. , Newall G. 
Published: July 2010

AbstractNearly ten years have elapsed since Korzhinskii proposed his basis of paragenetic analysis in 1957. During this period the method was developed and popularised by including diverse problems of physico‐chemical petrology and the study of mineralisation. In the process, definite progress has been made in solving theoretical and practical problems. The present review does not pretend to be a full discussion of research in this field: its aim is reassessment of the most important achievements in certain problems of metamorphism, granitic and syenitic magmatism, metasomatism and formation of ores.
Palaeocurrent determinations by magnetic fabric measurements on the Cambrian Rocks of St. Tudwal's Peninsula, North Wales
Authors: Crimes T. P. , Oldershaw M. A. 
Published: July 2010

AbstractThe relationship between depositional grain orientation and current direction is discussed, and a method to assist in distinguishing between depositional and deformational magnetic fabrics is suggested. Magnetic fabric measurements from Middle and Upper Cambrian strata at St. Tudwal's Peninsula are presented. In the Maentwrog Beds (Upper Cambrian) a correspondence is found between the trend of the maximum magnetic susceptibility axes and the trend of the palaeocurrent as deduced from sole markings. In the Caered Mudstones and Flags (Middle Cambrian) the directions of maximum magnetic susceptibility are used to indicate palaeocurrent trends.
On some sources of errors in phase‐equilibria investigations at ultra‐high pressure; phase diagram of silica
Authors: Ostrovsky I. A. 
Published: July 2010

AbstractLarge pressure gradients and unrecognizable variations of pressure occur when solid substances are compressee by cold anvils (pistons) and heated by internal heaters. To improve the reliability of the results the miniaturization of samples and preliminary firing of pyrophyllite (which transmits pressure) are suggested. The equilibrium coesite—stishovite may be empirically expressed as:Pkb = 85 + 0·364 T (°C)Stishovite must be playing an important role in the mantle at depths greater than 500 km. Quartz and stishovite do not coexist in nature whatever PT‐conditions are.
Additional observations on the evolution of Gryphaea
Authors: Philip G. M. 
Published: July 2010

AbstractThe view that Gryphaea became uncoiled as it evolved, recently presented by T. P. Burnaby (1965), is shown to be based on the incorrect use of a size dependent parameter. His result is largely the outcome of the larger mean size of the higher subzone specimens in Hallam's collections. When this size dependence is allowed for, then the results of Burnaby's method are similar to those given by Philip (1962). An additional treatment of Hallam's data is given and it is shown that the slopes of the reduced major axes fitted to Hallam's samples by Philip (1962) are an adequate index of the tightness of coiling (estimated by s/r) of the larger specimens in the samples. Limitations of Burnaby's method are briefly discussed.
Reconnaissance seismic refraction surveys in the Malvern Hills Area
Authors: Brooks Michael 
Published: July 2010

AbstractSeismic refraction profiles have been established in Eastnor Park (SO 745375) and in the Storridge area (SO 750486), respectively west and north of the Malvern Hills. The seismic results can be explained by a three‐layered subsurface configuration. Layers 1 and 2 are roughly equivalent to Silurian and Cambrian strata and layer 3 is regarded as Precambrian basement.Under both profiles the Cambrian is much thinner than at the southern end of the Hill range where Groom (1902) estimated a minimum thickness of 2,500 ft (762 m). In Eastnor Park the basement dips westwards at about 10° and is overlain by approximately 1,000 ft (305 m) of Cambrian strata. At the western boundary of the Malvern Hills the Cambrian appears to be cut out locally by a pre‐LIandovery fault.In the Storridge area the seismic results are consistent with a shallow basement overlain by a few hundred feet of Cambrian strata, as suggested in an earlier paper on the basis of gravity and magnetic interpretations (Brooks 1968).
The Ayres raised beach, Isle of Man
Authors: Ward C. 
Published: July 2010

AbstractThe area fringing the north coast of the Isle of Man, known as the Ayres, consists of beach deposits lying three or four metres above high‐tide level (about 6 m above O.D. at Douglas). This raised beach extends from Phurt on the east coast to Sartfield on the west where it is cut out by modern coastal erosion. The fossil fauna is recent in character; Lamplugh (1903) used this as a basis for correlation with other raised beaches and platforms around the island.
A rediscovered fossil locality at Shedden, near Burnley, Lancashire
Authors: Eagar R. M. C. , Williamson I. A. 
Published: July 2010

AbstractCarbonicola agrestis (Brown 1843), described with C. heyae, C. rugosa and C. smithii, were recorded from “Ironstone Shale” at or near “Sheden”, a locality lost for many years. Non‐marine bivalves closely comparable with Brown's figures of C. agrestis and C. heyae were recently discovered in an old tip at Shedden, about 6–5 km south‐east of Burnley. With other evidence the material suggests that Brown's species were collected from a small mine in this locality and from a horizon not more than 3.7 m above the Arley Mine.
A reply to “On the age of the Hoxnian Interglacial” by N. R. Page
Authors: Shotton F. W. 
Published: July 2010

AbstractThe recent paper by Dr. N. R. Page (1972) proposes a time scale for Pleistocene events in East Anglia and southwest Britain which most workers on this subject find incredible and which results in a suggested correlation with other regions, particularly the English Midlands, which completely negates the many years of patient work of stratigraphers and palaeontologists. This paper is intended to show that the claims to the absolute ages of the East Anglian deposits cannot be sustained and that the resulting correlations with the Pleistocene of other parts of Britain and abroad are quite unacceptable.
The Leannan Fault in the Malin Head Peninsula, Co. Donegal, Eire
Authors: Dickinson Barbara 
Published: July 2010

AbstractGeological evidence is presented confirming that, in the Malin Head area of Inishowen, the Leannan Fault follows the conjectural line of Pitcher (1969) and not the line proposed by Pitcher et al. (1964) and Riddihough and Young (1970).
The Ghirian tertiary volcanic province of Tripolitania, Libya
Authors: Almond D. C. , Busrewil M. T. , Wadsworth W. J. 
Published: July 2010

AbstractThe Ghirian volcanic province comprises three distinct units. An early (50–55 m.y.) phase of extensive plateau lava (basaltic hawaiite) eruption was followed by the emplacement of small phonolite domes (∼ 40 m.y.). After a long period of inactivity, a rejuvenation phase (< 12 m.y.ago) led to the formation of scattered minor volcanic centres, generally of basanitic composition, and carrying Iherzolite fragments. 39 new analyses illustrate the distinctive chemical characteristics of each episode. Differences in volume and composition between early and late basic volcanicity can be related to regional episodes of strong mantle convection in the early Tertiary and weak convection in the late Tertiary. The phonolites may be fractionates of an intervening injection of basic magma trapped at moderate depth. Continuing structural control was exerted on a regional scale by the zone of uplift and fracturing connecting the Ghirian area with Tibesti.
A gravity survey of Northwest Lancashire
Authors: Barker R. D. 
Published: July 2010

AbstractA survey involving 860 gravity measurements over the Fylde area of Lancashire is described. A line of movement in the pre‐Permian basement rocks is shown to cross the area from north north east to south south west forming the eastern edge of a deep sedimentary basin. Displacement of the Carboniferous along this line has reached 1000 m in places and was probably an important influence on Permo‐Triassic deposition in Northwest Lancashire.
Facies relationships in the Upper Devonian‐Lower Carboniferous of southwest Ireland and adjacent regions
Authors: Naylor D. , Jones P. C. , Matthews S. C. 
Published: July 2010

AbstractIn southwest Ireland 2,500 m of Upper Famennian to basal Namurian marine sandstones and mudstones, the Cork Beds, overlie rocks of Old Red Sandstone facies. Coastal exposures of the Cork Beds are interpreted as showing gradual upward change from alluvial strata, through thick subtidal and shelf sediments to pyritic muds. A review of recent palaeontological evidence shows that the thick shallow marine part of the Cork Beds is older than the major development of lime‐stones north of the Cork Harbour—Kenmare Une, whose equivalents to the south are in the condensed basinal sediments. The Lower Carboniferous portion of the Cork Facies is shown to be thicker in South Cork than in West Cork. In Lower Carboniferous times a positive area–the Glandore High–separated two sub‐basins with different depositional histories. Six palaeogeographic maps are used to demonstrate the progressive shift of facies belts as Lower Carboniferous marine transgression progressed. Finally, brief comparison is made with rocks of the same age in southwest England.
Jointing and minor tectonics of the Vale of Glamorgan between Ogmore‐By‐Sea and Lavernock Point, South Wales
Authors: Roberts J. C. 
Published: July 2010

AbstractJoints and faults were studied in Mesozoic and Avonian strata along 35 km of coast between Ogmore‐by‐Sea and Lavernock Point, Glamorgan, South Wales. Observations on joint and fault planes were recorded at 22 localities (i.e. approx. 750 stations), an analysis of which suggests the following. In the Mesozoic strata systematic joint patterns of tectonic origin exist with principal azimuths at 340°, 200° and 280°, with the more complex patterns characteristic of Triassic sequences, whilst a System of orthogonal microjoints (striking at 280°–190°) representa perhaps the earliest formed fractures in the Mesozoic strata. The joints in general formed early in the deformation of the area, whilst joints and faults can both be ascribed to a general northsouth compressive force. A study of fracture patterns in Avonian basement reveals a close similarity of trend, but there is little visible evidence to indicate much basement influence on cover tectonics.
The geological interpretation of gravity and magnetic surveys over the exposed southern margin of the Galway Granite, Ireland
Authors: Fairhead J. D. , Walker P. 
Published: July 2010

AbstractGravity measurements across the southern margin of the Galway granite, on the Islands of Gorumna and Lettermullen, reveal small positive Bouguer anomalies of amplitudes less than 40 g.u. associated with the denser country rock. These anomalies suggest that the ‘country rock’ is no more than a thin wedge, thickening southwards. Such a structure may form part of a large roof pendant or roof section with the true granite margin lying further south. Magnetic anomaly profiles across the granite contact reveal that the rock groups, making up the country rock, have distinct magnetic character which may provide a means of mapping their southern extent beneath Galway Bay.
Cuticular ultrastructure of a Cretaceous decapod crustacean
Authors: Dalingwater J. E. 
Published: July 2010

AbstractThe cuticie of the lobster Hoploparia longimana (Sowerby) from the Cambridge Greensand (Upper Cretaceous), when etched in E.D.T.A. and examined with the scanning electron microscope, reveals detail of ultrastructure not previously described from any fossil arthropod cuticle. The fibre patterns of laminae and inter‐laminae are described and interpreted by comparison with those in modern crustacean cuticles. Horizontal tubules at the laminae may represent a lamina membrane. The pore canals are round with fibrous walls and are surrounded by elliptical voids, possibly originally occupied by vertical fibres. Wider canals, around 15 μm in diameter, are probably setal ducts. The cuticle is now largely composed of an apatite.
The structure of the Skiddaw Slates in the Blencathra‐Mungrisdale area, Cumbria
Authors: Roberts D. E. 
Published: July 2010

AbstractFour phases of deformation (D1‐D4) and a ubiquitous non‐tectonic bedding‐cleavage are described. D1 structures are gravity collapse folds without an associated cleavage, formed before the extrusion of the Borrowdale Volcanics. Pre‐Bala folds recognised in the Volcanics are not readily observable in the Slates on a small scale, but may be present on a wider aspect. D2‐D4 folds and cleavages are end‐Silurian structures, the result of the main closure of the Lake District Geosyncline during the Caledonian Orogeny. D2 is the result of crustal shortening and is closely related in time to the emplacement of the Skiddaw Granite; D3 resulted from vertical shortening in conjunction with the intrusion of the Lake District Batholith; and D4 resulted from post‐granite shortening of the existing fold axes. A correlation of the history of deformation with those of other areas is also suggested.
Microfaunas, microfloras and the environmental stratigraphy of the Late Glacial and Holocene in Cardigan Bay
Authors: Haynes J. R. , Kiteley R. J. , Whatley R. C. , Wilks P. J. 
Published: July 2010

AbstractThe distribution of foraminifers, ostracods, diatoms and pollen is studied in cores from submarine boreholes. This reveals that the history of the Flandrian transgression is largely the record of the infilling of meltwater channels cut during the early Late Glacial with transgressive estuarine and finally marine deposits. It also supports the idea of the ‘climatic earliness’ of the Welsh seaboard at all stages. Estuarine deposits in excess of —51 m O.D. suggest that Late Glacial sea levels were initially as low as —60 m O.D. and support the idea that the Welsh ice withdrew before 14,000 years B.P. The sea‐level rise plots as a smooth curve but was probably episodic in its early phases.
Comments on the environments and faunas across the Ludlovian‐Downtonian boundary (upper silurian) at Siefton, Salop
Authors: Antia David D. J. 
Published: July 2010

AbstractA new temporary section across the Ludlovian‐Downtonian boundary (Upper Silurian) at Siefton (Nr Craven Arms), Salop, England, is described. The sediments present in the section were deposited in both intertidal and subtidal marine environments. The shelly faunas across the section are recorded and considered to be transported assemblages. Both burrowing and boring trace fossils occur in the presumed subtidal environments. Evidence for a late Whitcliffian marine transgression, following a marine regression is presented.
Late pleistocene rock‐basin lakes in South Wales
Authors: Culver S. J. , Bull P. A. 
Published: July 2010

AbstractLaminated silts and clays recovered by coring and drilling in Swansea Bay are shown to be of lacustrine origin. Similar deposits penetrated by boreholes onshore in the Swansea area have also been ascribed to a lacustrine origin by several authors; a map showing the shape and distribution of five lakes in this area has been produced. Stratigraphic relationships and palynological evidence indicate that the lacustrine conditions probably lasted from about 16,000 to 10,000 years B.P.
Comments on the environments and faunas across the ludlovian‐downtonian boundary (upper silurian) at siefton, salop
Authors: Antia David D. J. 
Published: July 2010

AbstractA new temporary section across the Ludlovian‐Downtonian boundary (Upper Silurian) at Siefton (Nr Craven Arms), Salop, England, is described. The sediments present in the section were deposited in both intertidal and subtidal marine environments. The shelly faunas across the section are recorded and considered to be transported assemblages. Both burrowing and boring trace fossils occur in the presumed subtidal environments. Evidence for a late Whitcliffian marine transgression, following a marine regression is presented.
Meltwater phenomena in the area between bala and corwen, North Wales
Authors: Rowlands B. M. 
Published: July 2010

AbstractPreviously unrecorded glacio‐fluvial phenomena are identified and mapped. These are shown to conform in part with the known southwest to northeast movement of meltwater from the wasting ‘Merioneth’ icecap in late Devensian time. A further series of meltwater channels and associated kames is also revealed, connecting southwards with the Dee Valley. Orientation of bedding within these latter kame deposits at Sarnau (971394) is also shown to accord with deposition by meltwater from an ice front to the southwest. Petrological analysis of igneous erratics within the Sarnau deposits suggests an origin entirely within the Arenig Mountains. It is thus postulated that the features relate to a late stage in the wasting of the 'Merioneth' ice cap, when a series of meltwater escape routes to the Dee Valley became progressively ice‐free, and that the newly‐discovered meltwater channel system is thus complementary to previously recorded phenomena.
Surface textures of regolith quartz from the Southern Pennines
Authors: Wilson Peter 
Published: July 2010

AbstractQuartz sand grains from the Millstone Grit grus deposits of the southern Pennines have been examined with the scanning electron microscope (SEM). Discrepancies exist in the published literature regarding the time and mode of formation for this material. Several of the observed grain surface features can be related to the diagenetic history of the parent rock, others to the more recent phase of rock decomposition. Evidence for both chemical and mechanical weathering is presented and a relative chronology of surface feature development outlined along with a discussion of the likely time of formation.
Prevention of beach erosion at Aberystwyth: A success story
Authors: Wood A. 
Published: July 2010

AbstractIn a previous paper in this journal (Wood 1978) the geological and human factors involved in coastal erosion at the north end of the Promenade at Aberystwyth were evaluated. It was concluded that only the addition of suitable material to the beach (replenishment) would halt erosion and protect this portion of the promenade. Even while the paper was passing through the press replenishment was in progress (Autumn 1977), and the purpose of this note is to evaluate its success and to look forward to the future.
A note on the glacial and late glacial history of caithness
Authors: Flinn Derek 
Published: July 2010

AbstractIt is generally accepted that in the last glaciation Scottish ice from the Moray Firth flowed to the northwest across Caithness depositing shelly drift. Examination of striae along the east coast of Caithness shows that some were formed by ice flowing into and not out of the Moray Firth. It is argued that the flow into the Moray Firth may have occurred in the last glaciation and that the shelly drift may be a relic of an earlier glaciation. The cliffs of Caithness were formed during the Loch Lomond Readvance and have since been raised isostatically and so have been protected from further marine erosion by their own wave‐cut platform which can be traced into Orkney where it intersects the present level.
A review of Middle Ordovician sedimentation in the St. Lawrence Lowland, eastern Canada
Authors: Harland T. L. , Pickerill R. K. 
Published: July 2010

AbstractMiddle Ordovician sediments of the St. Lawrence Lowland, eastern Canada, and its northeastward extension to St‐Siméon, are subdivided into the numerous formations of the Chazy, Black River and Trenton Groups. Details of each formation and interpretation of environments of deposition are presented and a coherent model for the development of the upper Middle Ordovician Trenton Group throughout the region is presented. In the southwest, around Montreal, a complete and continuous Middle Ordovician sequence is present and Trenton Group sediments overlie well‐developed tidal flat and lagoonal (Black River Group) and mixed shallow subtidal (Chazy Group) sediments. This sequence was deposited on a slowly subsiding, essentially flat, broad shelf environment. Northeastward from Montreal, toward the Montmorency Promontory of the Quebec City area, basal Middle Ordovician sediments become younger and the extent of the shelf area narrowed significantly. The latter resulted in skeletal shoal sediments (lower Trenton Group) developing closer to shore and concomitant less well‐developed clastic‐rich lagoonal sediments (Black River Group and basal Trenton Group). At Montmorency Promontory the shoal sediments (basal Trenton Group) accumulated along an irregular and rugged coastline. Northeast of the Promontory a steep onshore to offshore profile and rapidly deposited basal inshore clastics (Black River Group) precluded the deposition of skeletal shoals and rapid submergence promoted the early development of deeper shelf (middle and upper Trenton Group) and slope and basin (top Trenton Group, Saint Irénée Formation) sediments. In contrast, corresponding offshore sediments (middle and upper Trenton Group) in the southwest reflect a lower depositional gradient and more gradual subsidence. These patterns of deposition were determined by the interaction of the changing nature of the Ordovician coastline southwest, at, and northeast of the Montmorency Promontory and the variable subsidence rates influenced by the eastward evolving Taconic Orogen.
A new section around the Amaliae (Tonge's) Marine Band near Manchester, England
Authors: Chisholm J. I. 
Published: July 2010

AbstractAn excavation for a reservoir at Hartshead, Greater Manchester, has provided a section through part of the lower Coal Measures (Westphalian A). The identification of two marker bands, the Amaliae (Tonge's) Marine Band and the Meadowfarm (Cannel Mine) Marine Band enables the section to be correlated with the standard Lancashire sequence, with consequent revision to the published geological maps. Palaeocurrent data are also given. Trace fossil descriptions suggest differing facies associations of sandstones occurring adjacent to the marine bands in this area.
Repeated basement reactivation in the northeastern Appalachians
Authors: Currie K. L. 
Published: July 2010

AbstractIn the northeastern Appalachians crystalline, basement outcrops within a y‐shaped belt extending southwest from Bonavista Bay, Newfoundland, to Port aux Basques, and thence via the Cape Breton Highland to near Saint John, New Brunswick. Locally a Precambrian platformal sequence lies on the basement. Stratigraphic and isotopic evidence demonstrate that in the Saint John and northern Cape Breton regions, both basement and cover were remobilized about 600 million years ago, the basement probably for the second time. After deposition of a Cambro‐Ordovician cover, these rocks were again mobilized and intruded in mid‐Ordovician and Devonian time. Evidence for basement reactivation in Newfoundland, although fragmentary, is compatible with a similar history. Much of the basement gneiss is presently exposed in uplifted fault blocks.The observations can be explained in plate tectonic terms if the sedimentary accretion prism collapses during plate convergence, and is pushed onto the craton, which is itself thickened due to compressive stress. Because the edge of the cration is heated, due to thickening of both basement and sedimentary cover, the basement rises due to lowering of density by thermal expansion, and ultimately by partial melting. Depending on relative rates of heating, buoyant rise, and erosion, the process can lead either to a characteristic pattern of linear belts of reactivated basement which display positive gravity and magnetic anomalies, or to a chain of elongate gneiss domes exhibiting gravity lows. Application of the model to the northeastern Appalachians suggests that several continental fragments are present, and that basement rocks have been involved in repeated continental collision and breakup.