bluuebunny/crossref_metadata_2025_split huggingface dataset:
The thrust and normal faults of the Ullapool–Strath Kanaird region and their implications for NW Highland tectonics
Authors: Coward M. P. 
Published: January 2010

Synopsis
In the Ullapool to Strath Kanaird region of the NW Highlands the thrusts of the Moine thrust zone generally show a foreland propagating sequence but there are important anomalies. The Moine thrust itself appears to be a late structure, slicing across the earlier thrust stacks. There are several ages of normal fault movement. An early set formed synchronous with thrusting and involved extension in a WNW–ESE direction, parallel to general thrust transport, but also extension NE–SW, perpendicular to thrusting. These variations in movement indicate non-plane strain conditions, with important implications for section restoration. The early normal faults are either cut by or decouple on the Sole thrust to the Moine thrust system. There are late normal faults however, which are well-developed in the Ullapool area, and these are probably Mesozoic in age.
Hydrogeological provinces and groundwater flow systems in Scotland
Authors: Robins N. S. 
Published: January 2010

Synopsis
There are two principal hydrogeological provinces in Scotland: the Caithness and Moray Firth province, and the Midland Valley province (Central Lowlands). Regional groundwater flow patterns are developed in these provinces with deep-seated, but slow, transport of groundwater. Shallower local systems are also present. Annual recharge of up to 500 mm occurs to the more permeable aquifers at outcrop but is much reduced to less permeable aquifers and areas covered by till. Baseflow is related to the hydraulic conductivity of the aquifer and is highest in parts of Morayshire and Fife.
A review of radiocarbon dates on peat and wood from Holocene coastal sedimentary sequences in Scotland
Authors: Haggart B. A. 
Published: January 2010

Synopsis
158 radiocarbon dates from Holocene coastal sedimentary sequences are assessed in terms of their tendency of relative sea-level movement. Three subdivisions of greater, intermediate and lesser uplift history are made in order to assess the degree of synchroneity or diachroneity present in the data. The most successful demonstration of diachroneity is for the initiation of the mid-Holocene fall in relative sea-level. This may correspond approximately with the formation of the Main Postglacial Shoreline throughout Scotland. However on the national scale this shoreline may be a composite feature. A notable departure from the expected pattern of diachroneity is recorded for south-west Scotland.
An ancient manganese-iron deposit of freshwater origin, Islay, Argyllshire
Authors: Nicholson Keith 
Published: January 2010

Synopsis
Veins composed of manganese and iron oxides occur within the Dalradian Jura Quartzite (Argyll Group) on the SW coast of Islay. The manganese oxides, which are composed principally of hollandite with minor pyrolusite and rare groutite, frequently display a colloform texture centred upon silicate grains. In a single section an oolitic texture was displayed by hollandite in a hematite groundmass. Hematite and goethite, in variable amounts, constitute the iron oxides, and usually enclose fragments of the host quartzite. The manganese and iron oxides frequently occur as separate, discrete patches within the vein material. The geochemistry of the oxides shows that, of the target and pathfinder elements, only Ba attains elevated levels (up to 4.9%). The absence of enrichments in the diagnostic hydrothermal assemblage (As–Ba–Cu–Mo–Pb–Sb–Sr–V–Zn) and in the marine assemblage (Na–K–Ca–Mg–Sr; Co–Cu–Ni) imply that this is a freshwater deposit. This conclusion was confirmed by discriminatory scatter plots of Na vs Mg and (Co + Ni) vs (As + Cu + Mo + Pb +V + Zn) which indicate a fresh-water, non-hydrothermal origin for the veins. The oxides were deposited from groundwater which penetrated the Jura Quartzite via a local fault system probably in Permo-Triassic time. The veins have no economic potential as manganese ore and the prospect of related base or precious metal mineralisation is remote.
Palaeomagnetic dating of pseudotachylyte formation in the Lewisian complex
Authors: Piper J. D. A. , Poppleton T. J. 
Published: January 2010

Synopsis
Magnetic remanence is employed to date episodes of pseudotachylyte formation within the Lewisian terrane. In the Southern Zone on the mainland directions of magnetisation correlate with late stages of post-Laxfordian uplift and imply that these examples were either contemporaneous with the LM3 metamorphism or with early Torridonian rifting. In the Outer Hebrides the pseudotachylytes yield both mid-Proterozoic and Caledonian directions of magnetisation. The Proterozoic examples were formed late in the post-Laxfordian uplift cycle while the Palaeozoic examples are linked to formation of the Outer Hebrides thrust zone and presumably to the Caledonian thrusting on the mainland. The latter examples imply that differential uplift of the order of several kilometres has taken place between the Outer Hebrides and the Mainland since Caledonian times; their presence here explains why Torridonian and Lower Palaezoic cover rocks are not preserved in the former area.
The age of the South Connemara Group, Ireland, and its relationship to the Southern Uplands Zone of Scotland and Ireland
Authors: Williams D. Michael , Armstrong Howard A. , Harper David A. T. 
Published: January 2010

Synopsis
The South Connemara Group lies to the south of the Dalradian rocks of Connemara. It consists of approximately 3 km of interbedded pillow lavas, cherts, sandstones and conglomerates with significant amphibolite intrusives. Hitherto its age has been unknown although it has been contact metamorphosed by the Devonian Galway Granite. New palaeontological evidence suggests an early Ordovician age for the sequence. The petrofacies of the clastic units within the group, its structural style, age and tectonic position suggest similarities with parts of the Southern Uplands of Scotland and its equivalents in Ireland. The South Connemara Group bears greatest similarities to Tract 2 of the Southern Uplands. The age of the group supports the apparent SW to NE diachronism of clastic sedimentation in this part of the Caledonides. The proposed correlation imposes a constraint on the position of the Southern Upland Fault in Ireland.
Sedimentology and early diagenesis of the Lower Jurassic, Applecross, Wester Ross
Authors: Searl Alison 
Published: January 2010

Synopsis
The Jurassic strata at Applecross comprise 60 m of mixed siliciclastics and carbonates deposited in a variety of shallow marine environments including shallow carbonate shelf with patch reefs, oolitic shoal, restricted lagoon, beach and siliciclastic mudflats. Vadose cement fabrics, blackened carbonate allochems, evaporite pseudomorphs and plant remains indicate several phases of sediment emergence during deposition. Changes in the source of siliciclastic sediment during deposition are also evident. The complex nature of the sequence is related to interplay of a regional marine transgression across the Hebridean area and localised uplift immediately north of Applecross. Differential offshore subsidence continually modified the topography of the depositional basin altering the hydraulic regime in the Applecross area.
Stevensite, a smectite-group mineral from Corstorphine Hill, Edinburgh
Authors: Davidson P. J. 
Published: January 2010

Synopsis
Specimens of pectolite, from Corstorphine Hill, Edinburgh, were found to be coated by the smectite-group mineral stevensite. This is the first recorded occurrence of stevensite in Scotland, although the specimen was registered (as pectolite) in 1898. X-ray diffraction and spectrometry, infra-red and electron probe micro-analytical techniques were used to identify the material, which occurs as a brown gel-like phase, and is both intermixed with, and coating, the pectolite.
Manganese minerals in Scotland
Authors: Nicholson Keith 
Published: January 2010

Synopsis
Mining for manganese in Scotland first commenced in 1841. Trials were made at several sites, but no venture lasted longer than 5 years. Thirty-one manganese minerals are known to occur at 80 sites in Scotland, with over 70 localities recorded for manganese oxides alone. Birnessite, found at five sites, is the most common manganese mineral in Scotland. Most of the silicates and phosphates occur in Lewisian-Moine metamorphic rocks, while the majority of oxides are supergene in origin, varying in age from Early Ordovician to Pleistocene. Examples of birnessite and rhodochrosite formed by both hydrothermal and super-gene processes are known, and as such these are the only minerals to occur with more than one origin. The following manganese minerals have been recorded in Scotland: oxides: birnessite, braunite, chalcophanite, coronadite, cryptomelane, groutite, hollandite, jacobsite, lithiophorite, manganite, pyrolusite, pyrophanite, quenselite, ramsdellite, romanechite, todorokite, woodruffite; carbonate: rhodochrosite; phosphates: arrojadite, graftonite, jahnsite, rockbridgeite, triplite; silicates: axinite (undifferentiated), bustamite, ferrobustamite, johannsenite, knebelite, pyroxmangite, rhodonite, spessartine. Birnessite was first discovered in Scotland, and 13 of the above 31 minerals have their first British occurrence recorded in Scotland.
Fold and thrust structures in the Kintradwell ‘Boulder Beds’, Moray Firth
Authors: Roberts Alan 
Published: January 2010

Synopsis

The Kimmeridgian shales, sands and ‘boulder-beds’ exposed at Kintradwell Point in Sutherland display a complex series of ‘soft-sediment’ deformation features, which can be assigned to four categories, on the basis of both geometry and temporal relationship.

Small, closely-spaced, syn-depositional normal faults, throwing down to the S/SE.

Slump folds with intensely curvilinear hinges, produced by differential movement within a wet-sediment pile slumping to the south, obliquely away from the Helmsdale Fault.

‘Thrust’ faults together with related low-angle slides and extensional faults. These gravity-driven structures moved perpendicular to and away from the Helmsdale Fault. They represent a section through the leading edge of a large, detached gravity-slide.

Isolated, down-to-the-SE, brittle normal faults, tens of metres in length. These offset slump-fold and slide structures.

Structures belonging to category 4 may be the product of tectonic strain related to the opening of the Moray Firth Basin. The remainder are all thought to be local, gravity-driven structures, generated on a late Jurassic palaeoslope dipping away from the Helmsdale Fault.
Many geometric analogues for the Kintradwell structures are found not only in slump sheets documented elsewhere but also in the internal parts of contractional orogenic belts. Familiarity with the analysis of such ordered structures from within orogenic belts such as the Caledonides of the Scottish Highlands, facilitates an understanding of the section at Kintradwell.
Sequences similar to that at Kintradwell have been discovered during offshore hydrocarbon exploration in the North Sea. The observations presented in this paper have implications for the analysis of cores from such sequences.
Geochemistry and sedimentology of Grampian Group metasedimentary rocks, Upper Strathspey
Authors: Okonkwo C. T. 
Published: January 2010

Synopsis
The sedimentological attributes of the metasedimentary rocks of Upper Strathspey are inferred from their major and trace element geochemistry. The rocks of the Glenshirra Succession have high oxidation ratios and are of a lithic nature which suggests shallow water, probably alluvial, environments. The Corrieyairack Succession has turbiditic greywackes of a more basinal environment.

Within the Glenshirra Succession, the Allt Luaidhe Semi-psammite has semi-pelites with relatively higher Ba/Rb, CaO/Y and Sr/Y ratios which indicate its higher contents of detrital feldspars and suggest that its sediments were less “mature” than those of the other formations. Sorting of the sedimentary particles produced a compositional fractionation with the semi-pelitic fractions being enriched in TiO
2
, A1
2
O
3
, total Fe, MgO, K
2
O, P
2
O
5
, Cr, Y, Rb, Ba and Ni whereas the psammitic fractions are enriched in SiO
2
and Zr.

High concentrations of the large ion lithophile elements e.g. K, Ba, Rb and Sr, were found suggesting source rocks in middle or upper continental crustal layers, intruded by evolved granite. The
c.
1100 Ma Grenville crust is believed to be a major source of the sedimentary detritus.
A reappraisal of the supposed Ardersier Readvance, inner Moray Firth
Authors: Firth Callum R. 
Published: January 2010

Synopsis
Previous authors have proposed that the deglaciation of the Late Devensian ice sheet in the inner Moray Firth area was interrupted by the “Ardersier Readvance”. The morphological and lithological evidence indicates that the Ardersier features were not produced by a major readvance of ice but more probably represent glaciomarine deposits formed while ice occupied the Inverness Firth. Similarly the Late Devensian shoreline sequence of the area does not support the readvance hypothesis; instead it suggests that the sediments were deposited as relative sea level fell and the ice mass retreated westward.
Palynological evidence for the extent of the Loch Lomond Readvance in the Awe valley and adjacent areas, SE Highlands
Authors: Tipping R. M. 
Published: January 2010

Synopsis
Palynological evidence for the age of ice-dammed lacustrine deposits at an infilled lake basin at the SW end of Loch Awe shows the lake and the kame deposits forming the dam to be of Loch Lomond Stadial age. The absence of Devensian Lateglacial sediments at six sites within the Awe valley, and the virtual synchroneity in the earliest Flandrian of their basal biostratigraphic records also indicates ice cover in the valley during the Loch Lomond Stadial. This evidence is at variance with recent reconstructions of the extent of this ice advance in this part of Scotland. Similar lines of evidence from other localities in adjacent valleys suggest that the Loch Lomond Readvance in this region was of markedly greater magnitude than currently envisaged.
Late Devensian organic deposits beneath till in the Teith Valley, Perthshire
Authors: Merritt J. W. , Coope G. R. , Taylor B. J. , Walker M. J. C. 
Published: January 2010

Synopsis
Organic silts (Torrie Silts), dated by radiocarbon, arthropod fauna and pollen flora to the Lateglacial (Windermere) Interstadial and the early part of the Loch Lomond Stadial, have been discovered beneath till near Callander in the upper Teith Valley. The till overlying the Torrie Silts was deposited by a valley glacier which terminated in the vicinity during the Loch Lomond Stadial. A new radiocarbon date of 12,750 ± 70 BP has been obtained from plant detritus close to the base of the organic sequence. The profile at Torrie, which constitutes one of the longest polleniferous sequences through Lateglacial Interstadial and Loch Lomond Stadial deposits in Scotland, indicates a considerable time lag between the onset of the Stadial and the arrival of the valley glacier.
The deglaciation of Glen Croulin, Knoydart
Authors: Bennett Matthew 
Published: January 2010

Synopsis
The remarkable glacial geology of Glen Croulin has resulted from the interaction of regional ice flowing down Loch Hourn with local ice in Glen Croulin. The regional ice in Loch Hourn dammed up the valley mouth, while local ice occupied the upper part of the glen. This interaction probably dates from the Loch Lomond Stadial. The complex assemblage of landforms in Glen Croulin is interpreted here as a suite of ice marginal moraines and terraces, implying that the deglaciation occurred by active retreat as opposed to stagnation. A detailed picture of the pattern of this decay can be established and leads to the conclusion that the local ice in Glen Croulin reached its maximum extent and had begun to retreat prior to the maximum of the regional Loch Hourn ice.
The biostratigraphy and chronostratigraphy of BGS Borehole 78/4, North Minch
Authors: Graham D. K. , Harland R. , Gregory D. M. , Long D. , Morton A. C. 
Published: January 2010

Synopsis
The British Geological Survey’s offshore borehole 78/4 has provided one of the most complete late Devensian to Flandrian Quaternary successions observed in Scottish waters. Molluscs from this sequence have provided radiocarbon dates ranging from 12,785 to 8,240 years BP. These dates are discussed in the context of the palaeoenvironmental history of the succession as indicated by its floras and faunas. Concentrations of volcanic glass shards indicate an ash fall, apparently equivalent to the Vedde Ash of western Norway.
Geochemistry, provenance and climate of the Upper Proterozoic Stoer Group in Scotland
Authors: Stewart A. D. 
Published: January 2010

Synopsis
Stoer Group red beds, filling the lower part of a Proterozoic rift in NW Scotland, rest unconformably on Archaean gneisses strongly depleted in Th, Rb and K. The lowest sediments, despite their evident derivation from the gneisses, are relatively enriched in these elements (and also in Mg), indicating an additional, undepleted source. An analysis of vitric tuff from a member within the Group also shows high Rb, K and Mg, suggesting that much of the sequence was deposited under an intermittent rain of fine volcanic ash, now present as clay and chlorite in the finer grained fraction of the sediments. This helps to explain the low crustal residence age (τ ≃ 2.2 Ga) deduced from Nd isotope studies of shales in the Group.
Massive red siltstones and sandstones which appear at several levels in the Group owe their structureless nature to the seasonal wetting and drying of smectite. By analogy with vertisols the annual dry season was likely to have been 4–8 months, the rainfall 300–1200 mm and the palaeolatitude 10–30°, matching that deduced from the palaeomagnetism. Low rainfall is also suggested by the insignificant Ca depletion shown by certain tuff-free sandstones relative to the parental gneiss.
The geochemistry of alluvial sandstones higher in the Stoer Group (Bay of Stoer and Meall Dearg Formations) indicates a mixed source of 75% amphibolite facies gneisses and 25% siliceous sediments. The alluvial sandstones show even less depletion in soluble components than the basal sediments, suggesting high relief on the rift flanks whence they came.
Magnetostratigraphy of the Tertiary igneous rocks of Arran
Authors: Hodgson B. D. , Dagley P. , Mussett A. E. 
Published: January 2010

Synopsis
The Tertiary igneous succession of Arran is poorly known, partly because of a paucity of informative field relationships, so palaeomagnetic polarities and Ar–Ar dates have been measured to provide additional constraints.
New palaeomagnetic results for over 200 sites have been combined with published data. The Northern Granite has normal polarity (N), while the later Central Ring Complex has reversed polarity (R). All sampled quartz-porphyries are N and all felsites (apart from some intermediate direction (I) sites) are R, the only known correlations between polarity and petrography in the British Tertiary Igneous Province. The remaining petrographic types may be found with either polarity. All dykes sampled on the NW coast are N, as are 70% of those on the NE coast, but elsewhere R polarity predominates.
Radiometric dates show that the activity occurred approximately 61 to 58 Ma ago. It spanned at least the magnetic polarity sequence R–N–R, and although additional polarity intervals cannot be ruled out, a tentative succession consistent with R–N–R and with as few as possible recurrences of petrographic types has been constructed. The mean direction of magnetisation of the sites is not consistent with that of an axial, centred dipole for the present latitude: several explanations are offered.
Disruption of Dalradian stratigraphy along the Portsoy Lineament from new geological and magnetic surveys
Authors: Fettes D. J. , Leslie A. G. , Stephenson D. , Kimbell S. F. 
Published: January 2010

Synopsis
Intrusions, metavolcanic rocks and metasediments which crop out along a zone defining the Portsoy Lineament in the Cabrach area have a well-defined magnetic signature. Multidisciplinary surveys have revealed the regional scale of dislocations within the zone evidenced by the juxtaposition of contrasting Appin and Argyll Group successions. To the west of the lineament a metasedimentary sequence extending from the Blair Atholl to the Easdale Subgroup is correlated with established Dalradian successions to the south. Within and to the east of the lineament, distinctive metasedimentary and metavolcanic sequences have Argyll Group characteristics but cannot be correlated with the western succession. Further east these rocks pass into Southern Highland Group lithologies without the intervening calcareous beds which characterise this part of the Dalradian elsewhere. Major mafic and ultramafic intrusions are confined to the area within and to the east of the lineament and are commonly bounded by shear zones. The major dislocations in this area support the concept of a decoupled NE Grampian regional block and the fundamental role of the Portsoy Lineament in controlling basin development and subsequent tectonic, metamorphic and igneous events.
A local deep-water sediment failure on the NW slope of the UK
Authors: Strachan P. , Evans D. 
Published: January 2010

Synopsis
An example is described, from seismic evidence, of a local deep-water sediment failure on the slope to the west of the Isle of Lewis, an area which otherwise appears to be generally stable. The feature is about 4 km long in the downslope direction and lies above an escarpment at an approximate water depth of 1100 m. The loss of layering on the reflection profile, and the existence of infilled depressions, suggests that excess pore water pressures have been generated and subsequently dissipated. It is conjectured that the failure has been triggered by an earthquake, or possibly by internal wave action. The sediment body is thought to have failed by liquefaction acting retrogressively upslope.
The Síofra Gabbro, West Connacht, Ireland
Authors: Mohr Paul 
Published: January 2010

Synopsis
The Síofra Gabbro, considered to be of Paleocene age, is exposed on the now uplifted late-Tertiary erosion surface of the West Connacht plateau. It is a vertical cylindrical body emplaced into near-vertical Ordovician slates that carry a mild thermal aurcole. The intrusion is composed of labradorite-augite-olivine-leucogabbro containing cognate mafic xenocrysts. Although ‘Mg’ values close to 60 indicate a similar degree of magmatic evolution to that of the coeval alkaline dolerite dyke systems of West Connacht, the gabbro is distinctively subalkaline. It is also relatively enriched in alumina and depleted in both compatible and incompatible trace elements. The Síofra magma appears to have rested and fractionated at the top of a zoned belljar chamber in the upper crust.