bluuebunny/crossref_metadata_2025_split huggingface dataset:
The structural history of the Cheviot and adjacent regions
Authors: Robson D. A. 
Published: January 2010

Synopsis
Relief of NW to SE stress at the end of Silurian times led to intensive volcanic, followed by major and minor intrusive activity in the Cheviot region during the Lower Old Red Sandstone period. During the Upper Old Red Sandstone period, uplift and erosion took place, such that by the beginning of Carboniferous times, the roof of the granite stock was already exposed. In the Carboniferous period subsidence occurred, leading to the great accumulation of sediment in the Northumberland trough, with at least some deposition across the Cheviot region. Hercynian movements were represented by W–E compression throughout the NE of England and southern Scotland. In the sediments adjacent to the Cheviot igneous region, these movements were heralded by folding; they continued as shear-faulting both in the Cheviot igneous block and in the adjacent sediments and they were followed by the intrusion of the whin dykes and the Great Whin Sill. Tertiary movements began with the intrusion of the Acklington dyke, followed by N–S compression with shear faulting. A late phase of movement, responsible for much of the present-day topography, was manifested by normal faulting and tilting. Throughout the history of the region, fault movements were re-activated along Lower Palaeozoic trends.
The Metamorphism of the Dalradian rocks of Scotland.
Authors: Atherton Michael P. 
Published: January 2010

Synopsis
The metamorphism of the Dalradian rocks of Scotland is reviewed and commented on, attention being paid to the nature and spatial distribution of the zones and their significance in PT modelling. Reactions defining Barrovian and Buchan isograds are listed and figured and the importance of textural and chemical disequilibrium discussed. The effect of rock composition on the isograds is examined and a T-X diagram constructed to indicate the probable metamorphic mineral sequence for the average pelitic Dalradian composition. The history of ideas on the genesis of the migmatites is outlined and it is concluded that they may well be polygenetic, and those in the NE may even be of Pre-Caledonian age. The role of oxidation and reduction reactions is briefly mentioned and the late cooling reactions are described, from which it can be seen that the climatic assemblages have often been markedly modified.
The pressures and temperatures of the metamorphism, determined from phase considerations are plotted on a PT diagram and compared to the isotope results. Finally, evidence is used to suggest that although the fundamental cause of metamorphism might be a normal heatflow across the mantle/crust boundary and within the tectonic pile, the evidence at the present level indicates some of the metamorphism is due to high level magma and perhaps heat focussing along major structures.
Structural age of the Vagastie Bridge granite, Sutherland
Authors: Fergusson I. W. 
Published: January 2010

Synopsis
The Vagastie Bridge granite is observed to cut folds associated with the main metamorphism of the surrounding psammites of the Moine assemblage, confirming recent radiometric evidence that the granite belongs to the suite of Caledonian Newer Granites in the Northern Highlands, and is not equivalent to the Carn Chuinneag granite.
Palaeomagnetism and palaeogeography of the Southern Uplands block in Ordovician times
Authors: Piper J. D. A. 
Published: January 2010

Synopsis
The major Ordovician igneous outcrops within the Southern Uplands were studied to evaluate the position of this region with respect to adjacent crustal plates during the later history of the Iapetus Ocean. Post-Arenig, pre-Caradocian gabbros and serpentinites of the Ballantrae Complex yield palaeomagnetic poles of 26°E, 10°S (dψ = 10.9, dχ = 18.8°) and 27°E, 12°S (dψ = 5.5, dχ = 9.7°) respectively after a.f. and thermal cleaning. Although 95 per cent confidence circles overlap with other British Ordovician data, magnetic inclinations are systematically shallower than contemporaneous results from England and Wales and correlate closely with other data from N of the Southern Uplands Fault line. A similar result is found from palaeomagnetic study of the (Lower Caradocian) Bail Hill Volcanics. The palaeomagnetic results support faunal and tectonic evidence that the major crustal separation in Ordovician times existed between the Southern Uplands and the northern Lake District. The visible ophiolite slices along the approximate line of the present Midland Valley represent pre-Llanvirnian obduction in a northerly direction of an earlier ocean basin.
Folding and thrusting in the upper Glen Oykel area, Assynt
Authors: Milne K. P. 
Published: January 2010

Synopsis
The earliest tectonic event affecting Lewisian, Torridonian and Cambrian rocks in upper Glen Oykel involved a tight overturned syncline and anticline, the common limb of which developed into a previously unrecognized thrust, named here the Glen Oykel Thrust. The Loch Ailsh Syenites were probably intruded after this thrust. The disruption of the Torridonian rocks by the earlier thrust caused the Assynt Thrust to deviate sharply to remain within these sediments. In quartzites below the Assynt Thrust deformation is concentrated at the centre of an eastward bulge in the thrust surface.
A Geophysical Survey of South Kintyre
Authors: Wilson C. D. V. 
Published: January 2010

Synopsis
Seismic, gravity and magnetic data indicate a basin of Old Red Sandstone, probably fault bounded and about 1 km deep, between the south coast of Kintyre and Sanda Isle, where the Dalradian basement has been uplifted.
A gravity high near Southend is interpreted as due to concealed faulting in the southern limb of the Campbeltown syncline, together with a hidden basic intrusion. Adjacent to this high there is a chain of minor intrusives with weak magnetic anomalies. The deeper faulting in the Dalradian, the shallower faults in the Old Red Sandstone, the hidden basic mass and the outcropping intrusions may all be tectonically related. The structures may be part of the Highland Boundary Fault zone.
Basic minor intrusions in the Lewisian gneisses of southern Lewis, Outer Hebrides
Authors: Taft M. B. 
Published: January 2010

Synopsis
A structural study of basic minor intrusions of southern Lewis gives evidence for three distinct phases of intrusion, separated by phases of folding. Dates of structurally comparable intrusions on South Rona and the Scottish mainland suggest that at least one of the igneous phases on Lewis may have been intruded during the Laxfordian orogenic episode. The recognition of three different phases of basic activity, and the similar mineralogies of these, and intrusions elsewhere in the Lewisian, implies that detailed structural studies are necessary in order to express their significance in overall Lewisian history.
Origin of complex sulphide nodules related to diagenesis of lacustrine sediments of Middle Devonian age from the Shetland Islands
Authors: Hall A. J. , Donovan R. N. 
Published: January 2010

Synopsis
A laminated, carbonaceous-calcareous-siltstone facies (the Devonian Upper Melby Fish Bed, Shetland) of non-glacial varve origin deposited in a tropical, stratified lake, shows a complicated diagenesis. Sulphide nodules in this sequence, containing pyrite, chalcopyrite, covellite, bornite, sphalerite, galena and tennantite, show an equally complex development. The first period of growth produced a concentric zonation of pyrite and pyrite with sphalerite and galena. Following fracture of the nodule, Cu, Fe-sulphides replaced pyrite. Pb, Zn and As were remobilised and/or introduced at this time. It is probable that lacustrine regression and transgression greatly affected the chemical properties of groundwaters and led in part to the complicated nodule and host rock diagenesis. The nodules were later cut by small veins of tectonic origin.
The Camas Malag Formation: an interbedded rhythmite/conglomerate sequence of probable Triassic age, Loch Slapin, Isle of Skye
Authors: Nicholson R. 
Published: January 2010

Synopsis
The Camas Malag Formation, comprising interbedded rhythmites and orthoconglomerates, and lying unconformably on a very irregular surface of carbonate rocks of the Lower Palaeozoic Durness Group, is interpreted as a lacustrine deposit of Triassic age.
Boudins in adjacent Durness carbonates of rhythmite lithologies identical to those of the Formation are regarded as deformed fragments of tabular extensions of the latter deposited in cavities parallel to the bedding of the Durness rocks of the lake floor. They provide a minimum age for a deformation phase, earlier than the contact metamorphism produced by the Beinn an Dubhaich granite, in which dolerite sheets intrusive into Durness rocks also were deformed.
Intertidal sediments in the Auchenhew Beds (Triassic) of Arran
Authors: Pollard J. E. , Steel R. J. 
Published: January 2010

Synopsis
Study of a 45 m succession of the Auchenhew Beds (Triassic) of western Arran, with a record of halite pseudomorphs, symmetrical ripple marks, flaser, wavy and lenticular bedding, bimodal palaeocurrents and particular vertical arrangements of lithologies and structures, has provided evidence of intertidal conditions, probably within the context of a relatively arid, low energy, muddy shoreline. The new observations lend support to earlier suggestions of a marine connection and influence at this time and necessitate some reconsideration of the environmental significance of trace fossils previously described from this area.
The influence of bedrock on heavy mineral content of streams within a glaciated area of Perthshire
Authors: Abdalla A. Y. , Whyte F. 
Published: January 2010

Synopsis
A systematic collection and comparison of heavy minerals from stream sediments, glacial deposits and bedrock in the Glen Artney–Glen Lednock area shows that, despite glaciation and the influx of foreign material, the present heavy mineral distributions in streams clearly reflect the local geology.
A magnetic survey of the aureole around the Cheviot granite
Authors: Robson D. A. , Green A. G. 
Published: January 2010

Synopsis
A total field intensity map of the Cheviot granite stock and its aureole has been constructed from a ground-level proton magnetometer survey. Measurements on rock specimens, together with computer modelling, show that: (1) The andesitic lava of the aureole and the marginal variety of granite have high susceptibilities, but the unmetamorphosed andesite and rhyolite, and the granophyric and Standrop varieties of granite have lower susceptibilities; (2) The junction between the metamorphosed andesites and the underlying marginal granite forms a dome-like surface; (3) Some vertical movement on the Breamish fault and horizontal movement along the Harthope fault has occurred; (4) There are many xenoliths of metamorphosed andesite within the granite; (5) A shallow basin of granophyric and Standrop varieties is thought to lie within the central region of the granite stock; (6) The small negative anomaly over the Breamish fault may indicate that the marginal granite is only thin in that area; (7) The Biddlestone laccolith persists northward beneath the lava from Biddlestone quarry to the Breamish fault.
The geology and origin of narrow closed channels in the Sound of Jura
Authors: Evans D. , Ruckley N. A. 
Published: January 2010

Synopsis
Geological and geophysical investigations in the southern part of the Sound of Jura reveal numerous deep and narrow closed channels in a sequence of thick post-glacial muds. It is proposed that the channels were formed subsequent to the deposition of the sediments by the erosive action of the strong tides observed in the Sound. Several problems related to this mode of origin are considered, but more data are required to provide greater insight into the post-glacial history of the Sound.
The stratigraphical setting of the Cairnsmore of Fleet Pluton, Galloway
Authors: Cook D. R. , Weir J. A. 
Published: January 2010

Synopsis
The granitic pluton of Cairnsmore of Fleet was intruded into the Moffat Shales (Caradoc-Fronian) and an overlying flysch facies. The flysch is divisible into two formations: the Craignell Formation, in the NW of the area, and the Knockeans Formation, to the SE. Within the Craignell Formation, an evolution of greywacke facies from basic through lithic to silicic is recognized, the base being diachronous from Idwian in the SE upwards to early Fronian in the NW. The Knockeans Formation, deduced to be the youngest unit, completes the evolutionary sequence of the greywackes from basic to a silicic facies, and is correlated with the Hawick Group (Telychian or later). The anomalous NW encroachment of flysch over pelagic facies may relate to a sedimentary source within a ridge located along the Iapetus oceanic suture.
The geology of an undersea tunnel at Irvine Bay, Ayrshire
Authors: Anderson J. G. C. , Gayer R. A. 
Published: January 2010

Synposis
A 2 km long sea outfall tunnel and associated site investigation reveal a sequence of gently dipping strata of Productive Coal Measures (West-phalian) intruded by a Tertiary porphyritic basalt dyke, by a Permian volcanic neck and by Permian dykes of alkaline affinities. The stratigraphy and structure represent a westward extension of the north Ayrshire basin.
The Devonian sedimentation and tectonism of a rapidly subsiding, semi-arid fluvial basin in the Midland Valley of Scotland
Authors: Wilson Alan C. 
Published: January 2010

Synopsis
Early Devonian fluvial sedimentation took place in a large, late-orogenic basin bounded by actively-subsiding high-angled faults. Deposition of gravels and sands took place on mountain-fringing bajadas from sheetfloods and braided streams; sands, silts and clays were deposited in adjacent flood-plains. Basin-margin faults, notably the Highland Boundary Fault, controlled subsidence of an elongate depositional basin and when movement on these was sufficiently rapid, coalescing bajadas were constructed. When the rate of source area uplift/depositional basin subsidence decreased, the uplands were reduced and floodplains initially encroached on to the inactive bajadas before extending over the former source areas.
The Devonian sedimentary rocks of the Midland Valley which accumulated under semi-arid conditions, indicate that varying rates of source uplift/depositional basin subsidence were the dominant controls influencing the nature of the depositional processes. Moreover the various vertical sequences of genetically-different deposits found in the study area also occur in other similar alluvial basin deposits and a model is formulated to demonstrate that these successions reflect a limited number of distinct evolutionary tectono-sedimentary sequences.
Facies breaks in the Scottish Passage Group and their possible correlation with the Mississippian—Pennsylvanian hiatus
Authors: Read W. A. 
Published: January 2010

Synopsis

The Scottish Passage Group (Namurian E
2
to Westphalian A) contains many minor disconformities, but its thickest and most complete development in the Kincardine Basin east of Stirling reveals only three major depositional breaks or facies changes sufficiently important to be considered as possible correlatives of the Mississippian-Pennsylvanian hiatus of North America. They are here named Horizons 1 to 3.

Even in the area of maximal subsidence, Horizon 1 just above the Castlecary Limestone is marked by deep channelling. Despite the following flood of coarse sandy detritus, widespread marine transgressions continued (Nos. 1 to 2 Marine Bands). Horizon 2, which lies just above No. 2 Marine Band, heralded a regressive period with meandering river environments and only one local marine incursion. Above No. 3 Marine Band Group with its renewed widespread marine transgressions, Horizon 3 marks the onset of another regressive period when marine bands became impersistent, thin and faunally impoverished, e.g. Nos. 5 and 6 Group, overbank ‘fines’ were seldom preserved and braided rivers possibly became dominant.
Horizon 1 is much the best example of a major regression during the Scottish Namurian. Nevertheless biostratigraphical evidence favours Horizon 2 as being more probably equivalent to the Mississippian-Pennsylvanian hiatus.
Highland Border rocks at Loch Lomond and Aberfoyle
Authors: Henderson W. G. , Fortey N. J. 
Published: January 2010

Synopsis
Serpentinites, spilites, rudites, arenites and black slates at the Highland Boundary between Loch Lomond and Aberfoyle display a complex history of sedimentation, alteration and tectonism. Fragmental serpentinites, probably of sedimentary origin, occur at Balmaha, Loch Lomond, and at two other localities at the Highland Boundary N and W of Kirriemuir. Cleaved arenites and rudites contain fragments of ultrabasic rock including silicified serpentinite. The serpentinites were not intruded into the Highland Boundary Fault-zone, but had a history of uplift, erosion and displacement prior to major faulting in the Devonian.
Garnetiferous hornblende-schists near Aberfoyle are more highly metamorphosed and deformed than adjacent black slates and nearby Dalradian greywackes. Probably dynamothermal in origin, they resemble hornblende-schist slivers in the soles of allochthonous ophiolitic thrust-sheets.
The diverse Highland Border rock-types probably formed in a restricted ocean basin and were brought into contact with the Dalradian by crustal shortening during the Grampian orogeny.
Early Wenlock acritarchs from the Knockgardner and Straiton Grit Formations of Knockgardner, Ayrshire
Authors: Dorning Ken J. 
Published: January 2010

Synopsis
Palynomorphs recovered from three samples of the Silurian at Knock-gardner, Ayrshire, show well preserved acritarchs of a moderate diversity assemblage from the Knockgardner Formation, and a low diversity assemblage from the Straiton Grit Formation. The taxa recorded establish an early Wenlock age for the Knockgardner Formation, where the shelly macrofossil age is inconclusive.
The geochemistry of the Strathconon amphibolites, Northern Scotland
Authors: Winchester J. A. 
Published: January 2010

Synopsis
The Strathconon ortho-amphibolites were intruded into Glenfinnan and Loch Eil Division metasediments of the Moine Assemblage before the area was deformed in late Precambrian time. A chemical study has indicated that they consist of a single suite of variously fractionated tholeiitic sills and dykes which can be distinguished chemically both from the Y-poor amphibolites of the Morar Nappe and from more Y-rich amphibolites within the Central Ross Nappe spatially associated with the Quoich Line in Inverness-shire. The chemical distinction between amphibolites from the two nappes requires that major transport of the overlying Central Ross Nappe occurred after the intrusion of the basic sills.
A geometrical study of the Arnaboll and Heilam thrust sheets, NW of Ben Arnaboll, Sutherland
Authors: Coward Michael P. 
Published: January 2010

Synopsis
The geometries of thrusts in the Arnaboll and Heilam sheets, part of the Moine thust zone of NW Scotland, are described using branch line maps, which are the projections on to a map of the lines where thrusts join, and also cut-off maps, which are the projections of where thrusts cut through the strata. The thrusts are shown to have developed in a WNW propagating piggy-back sequence; structures developed on the lower thrusts cut or fold earlier higher level thrusts. Nowhere do thrusts cut down stratigraphy in the transport direction, and a previous claim that the Arnaboll thrust was out of sequence was based on a mis-correlation of thrusts.
The pyroclastic rocks and rhyolitic lavas of the Eastern Red Hills district, Isle of Skye
Authors: Bell Brian R. 
Published: January 2010

Synopsis
Mixed pyroclastic rock accumulations in the Eastern Red Hills district of the Tertiary igneous centre of Skye show a wide range in composition and mode of formation. Prior to this investigation these volcanic products were interpreted as vent infillings. It is shown that this model is unrealistic, as detailed mapping demonstrates that they are bedded, subaerial and subaqueous deposits. Chaotic, polylithic agglomerates, at least 300 m thick, are preserved in a ring-faulted mass in the Kilchrist area and are intercalated with thin acid tuffs, basic tuffs (grading towards coarser material) and ignimbrites. A hyaloclastite horizon is also present within the sequence. It is concluded that these accumulations of pyroclastic rocks do not show close genetic links with the later, spatially-associated granites of the Eastern Red Hills Centre, but may have originated by explosive volcanism triggered off by earlier events in the Skye Centre. Later subaerial and subaqueous processes greatly modified their primary appearance. Intercalated with the pyroclastic rocks are rhyolite lavas which are associated with the subvolcanic granites of the district. These lavas provide evidence of the close connection between surface volcanism and subvolcanic activity in the Skye Centre.
The sedimentology of the Lower Old Red Sandstone near New Aberdour, Grampian Region
Authors: Sweet I. P. 
Published: January 2010

Synopsis
The Lower Old Red Sandstone exposed on the coast near New Aberdour can be divided into a lower sandstone and conglomerate formation and an upper sandy mudstone formation which contains several sandstone lenses in its upper part. The lower formation can be further subdivided into four lithofacies assemblages (Facies 1A to 1D) consisting of, respectively, debris flow conglomerates, stream channel deposits, proximal alluvial fan deposits, and distal fan/sandflat deposits. Facies 2A of Formation 2 consists of a mud flat (playa) facies, containing evidence for pedogenesis (calcretization), and bioturbation, whereas Facies 2B, the sandstone lenses, reflect a return to higher energy, probably alluvial fan, deposition. The sediments were laid down in a small fault-bounded basin. The influence of tectonic activity and fan sedimentary processes are reflected in fining upwards ‘megasequences’ and ‘sequences’ respectively. Periods during which some fan segments and the adjacent playa received little sediment are reflected in the occurrence of numerous calcrete layers in the mudflat/playa facies.
Palaeomagnetism of the Sarclet Sandstone (Orcadian Basin): age perspectives
Authors: Storhaug K. , Storetvedt K. M. 
Published: January 2010

Synopsis
Palaeomagnetic results from the Sarclet Sandstone Formation, stratigraphically positioned near the base of the Old Red Sandstone (ORS) sequence of Caithness, suggest the presence of two different axes of magnetization, with Dec. 211, Inc. 33 and Dec. 191, Inc. 6 respectively. The most steeply inclined magnetization is in correspondence with results from Scottish Lower Old Red Sandstone volcanics indicating that the age of the Sarclet Sandstone dates from the topmost Silurian-lowermost Devonian. The abundant clasts of basalts in the underlying Sarclet Conglomerate give further substance to the notion that the Lower Old Red Sandstone volcanics, which have a wide distribution in central and southern regions of Scotland, also occurred in the Caithness/Moray Firth area. It is concluded therefore that the Orcadian Basin developed concurrently with the ORS basins of the Midland Valley and the Scottish Borders. It is inferred that the second magnetization (with shallow inclination) was imposed at around Middle Devonian, but owing to a relatively early silica cementation the Sarclet Sandstone was not susceptible to acquiring the “Permian” magnetization overprint that is strongly developed in the higher stratigraphic units of the Caithness Old Red Sandstone.