bluuebunny/crossref_metadata_2025 huggingface dataset:
Lithostratigraphical subdivision of the Triassic Sherwood Sandstone Group in west Cumbria
Authors: Barnes R. P. , Ambrose K. , Holliday D. W. , Jones N. S.
Published: December 2009

The subdivisions of the Sherwood Sandstone Group, previously recognized on geophysical and lithological criteria in boreholes offshore in the East Irish Sea Basin, can be identified in the onshore exposures and boreholes of west Cumbria. The term St Bees Sandstone Formation is here restricted to the lower, fluvial, fine-grained sandstone, with claystone and siltstone partings, exposed around St Bees. This formation is sharply overlain by softer and coarser grained, aeolian and subordinate fluvial sandstone, which contains abundant, well-rounded aeolian sand grains, referred to the newly defined Calder Sandstone Formation. Higher sandstone has been separated from the Calder Sandstone Formation by its finer grain size and by geophysical log signatures. This is referred to the Ormskirk Sandstone and is dominantly aeolian in origin. Similar divisions of the Sherwood Sandstone Group can be recognized in the Carlisle Basin, and may also be present in other onshore areas, but await formal definition.
The pattern of faulting across the western sector of the Market Weighton Block, Vale of York
Authors: Hawkins T. R. W. , Aldrick R. J.
Published: December 2009

The results of recent water well drilling and numerous resistivity depth soundings have shown that the western sector of the Market Weighton Block is intensely faulted. The faulting includes narrow north-east-trending grabens, resulting from re-activation of faults that originated during Variscan movements in the Upper Carboniferous sequences of the concealed Selby and main Yorkshire coalfields. These faults are not directly related to the nearby Howardian-Flamborough Head or Peak Trough fault systems.
Emplacement and diagenesis of gypsum and anhydrite in the late Permian Raisby Formation, north-east England
Authors: Lee M. R.
Published: December 2009

Cavities, pores and crystal pseudomorphs which are lined or filled by calcite are ubiquitous in Raisby Formation dolostones at outcrop in north-east England. Their distribution in most exposures is random on a metre scale. On a smaller scale, cavities, pores and crystal pseudomorphs are most numerous in bioclastic and resedimented beds. Deep borehole cores of the Raisby Formation contain nodules and euhedral crystals of gypsum and anhydrite of very similar size and shape to the cavities and pseudomorphs. This indicates that calcium sulphates were once abundant in the Raisby Formation at outcrop, but almost all have been removed subsequently.

Calcium sulphate minerals were formed early in the diagenetic history of the Raisby Formation, predominantly by selective replacement of carbonate rocks. Gypsum was precipitated first, probably as a by-product of dolomitization, by brines refluxing basinwards through the Raisby Formation from the hypersaline Zechstein Sea during deposition of the Edlington Formation and the Hartlepool Anhydrite Formation. Later, replacive anhydrite formed following both pressure-solution and dehydration of the gypsum. During further burial, some anhydrite was replaced by barite, dolomite and sphalerite. Upon uplift of the Raisby Formation during the Tertiary, anhydrite rehydrated to porphyroblastic gypsum and this was then dissolved by meteoric groundwaters. The resultant pores were lined or filled by two generations of calcite and also, locally, by kaolinite. The earlier calcite generation is luminescent and was precipitated partly as a passive cement and partly by replacement of surviving gypsum and anhydrite, a reaction thought to have been mediated by sulphate-reducing bacteria. The later calcite generation is predominantly non-luminescent and was precipitated from near-surface meteoric groundwaters.
Palynology of the Dinantian Lower Border Group of the Solway Basin
Authors: Mahdi S. A. , Butterworth M. A.
Published: December 2009

Miospore assemblages from the upper part of the Lower Border Group in Tarras Water, near Langholm, Dumfries and Galloway, are assigned to the
Lycospora pusilla
(Pu) Zone and the
Knoxisporites triradiatus–K. stephanephorus
(TS) Zone. Comparisons with similar assemblages from strata dated on their foraminiferal and/or conodont content suggest that the Tarras Water assemblages are early Visean, ranging from Chadian to Holkerian in age. Re-examined samples from the Bewcastle and Cambeck beds in the Bewcastle Anticline of Northumberland are assigned to the upper part of the Pu Zone and to the TS Zone respectively, suggesting that they are of Arundian and Holkerian age. Lycospores are more abundant in assemblages from the more marine Bewcastle sequence than in assemblages from Langholm sequence farther west. Such marked lateral changes of facies result in an eastward and northward reduction in numbers of stratigraphically useful fossils, creating uncertainty over dating and correlation of the Lower Border Group in this area. The present work suggests that the recently published correlations between sections in the Langholm–Newcastleton and Bewcastle areas may need to be revised.

Several species that were not previously known from Britain or north-west Europe, but which may be of stratigraphical value, have been recorded. Two new species are described:
Neoraistrickia variabilis
sp. nov. and
Schopfites claytonii
sp. nov.
Field relationships, geochemistry, and tectonic context of the Tertiary dyke suites in Staffordshire and Shropshire, central England
Authors: Thompson D. B. , Winchester J. A.
Published: December 2009

Field and petrographic data relating to the historically important dyke rocks in Shropshire and Staffordshire are reviewed and trace element geochemistry is used to show that separate dyke suites can be differentiated chemically.

The dykes have usually suffered late-stage feldspathization, analcitization, mineralization and weathering, making it difficult to characterize them petrographically. The whole-rock geochemistry described in this paper shows that in Shropshire two tholeiitic suites occur, around Acton Reynald and between Clive and Grinshill, while in Staffordshire alkaline basaltic dykes in the northern Butterton–Swynnerton area are chemically different from those in the southern Yarnfield–Norton Bridge area. These latter suites were derived from different magmatic sources. Chemical comparisons with the nearest suitably aligned Tertiary dyke sets in Anglesey and north Lancashire reveal broad, but not precise, comparability with the Shropshire and Staffordshire dykes respectively. It is argued that dyke emplacements were probably vertical rather than lateral and largely took advantage of pre-existing fracture patterns.

The discovery of distinct geochemical suites permits reinterpretation of fission track dating relating to dyke emplacement in the late Cretaceous–early Palaeocene phase of the British Tertiary Volcanic Province. The timing of emplacement of the Shropshire dykes accords well with the existence of a north-east-south-west tensional palaeostress field across the British Tertiary Volcanic Province both before and while the effects (
c.
62 Ma) of the Icelandic mantle plume and dome were first apparent and an abortive Gallic sub-plate was developing. Younger K-Ar and fission track dates in Staffordshire (at 52 and 54 Ma respectively) may relate to resetting of the apatite clock by late-stage hydrothermal alteration. A younger, less reliable K-Ar date in Shropshire (50 Ma) may relate to Cu–Pb–Zn–Co–Ni–V mineralization. The north-north-west–south-south-east Staffordshire dykes may relate generally to emplacement in the same stress field, but their alignment may also have been influenced by inherited upper-crustal Malvernoid fractures in the underlying Midlands microcraton. Post-intrusive normal, oblique and wrench faulting, consistent with later Tertiary and Neogene stress fields, affected dykes in Shropshire, but similar effects in Staffordshire are less well documented.
Pelmatozoan (crinoid?) columnals from the Hirnantian (Ordovician, Ashgill) of Keisley, Cumbria, UK
Authors: Donovan S. K. , Wright A. D.
Published: December 2009

Few pelmatozoan faunas have been recorded from the Hirnantian. A Hirnantian columnal fauna from rottenstones above the Keisley Limestone in the Cross Fell Inlier at Keisley, Cumbria, includes a new species of disparid crinoid,
Ectenocrinus britannicus,
the youngest known member of this genus. Columnal morphotaxa include
Bystrowicrinus
(col.) spp.,
Bystrowicrinus?
(col.) sp.,
Cyclocyclicus?
(col.) sp.,
Cyclocharax
(col.) sp.,
Particrinus
(col.) sp. or
Comptocrinus
(col.) sp., and
Pentagonocyclicus
(col.) spp. This fauna shows some similarities with that of the Hirnantian Glyn Formation of Gwynedd, Wales, but is closer to certain Rawtheyan faunas, such as that of the Rawtheyan Rhiwlas Limestone, perhaps emphasizing the relict nature of Hirnantian pelmatozoan faunas.
Effects of a Westphalian channel on coal-seam geometry: a reappraisal of the ‘Dumb Fault’ of north Derbyshire
Authors: Guion P. D. , Jones N. S. , Fulton I. M. , Ashton A. J.
Published: December 2009

The ‘Dumb Fault’ is a belt of Westphalian A (Langsettian) disturbed strata, that has been re-examined in an opencast mine in Derbyshire. The Deep Hard Seam is absent beneath the ‘Dumb Fault’, and anomalously thick coals occur on either side of the belt. A swilley, consisting of an elongate depression infilled in its lower part with impure coal, is present in the overlying Deep Soft Seam, and anticlinal folds occur in underlying seams. The ‘Dumb Fault’ is not a fault, but a minor channel system, that was subject to episodes of bank collapse which removed and displaced peat masses, forming the anomalously thick coal. Abandonment of the channel left an unplugged reach, which was filled with plant debris forming the swilley. Burial compacted the thickened displaced peat masses, with the anticlines in the underlying seams developing to accommodate the compaction. The potential adverse effects on mining of the features described include loss of coal tonnage, problems of excavation, highwall failure, difficulties in digging clean coal and changes of seam gradient.
Spectral gamma-ray and palynological characterization of Kinderscoutian marine bands in the Namurian of the Pennine Basin
Authors: Davies S. J. , McLean D.
Published: December 2009

Detailed sedimentological, spectral gamma-ray and palynological sampling of three sections through the Kinderscoutian R
1c
Ammonoid Biozone in a north–south transect across the Pennine Basin allows the recognition of features which are diagnostic of maximum flooding surfaces in diverse depositional settings. Data from ammonoid-bearing marine horizons provide a set of criteria which are applicable to the recognition of maximum flooding surfaces in depositional situations in which marine macrofauna are not necessarily preserved. Spectral gamma-ray data for marine bands include high U (>6ppm), low Th/U (<3.8) and commonly low Th/K (<6). Palynological characteristics reflect basin-wide changes in vegetation related to sea-level fluctuations and are diagnostic regardless of depositional setting. Marine bands are characterized by a peak in ‘hinterland’ microflora associated with coniferalean ‘super-hinterland’ elements and a coincident decline in the lowland ‘forest mire’ and ‘coloniser’ microfloral abundances. These criteria are used to identify candidate correlatives of marine bands in sections representative of a deep basinal setting (Blake Brook, North Staffordshire) and an unstable, turbidite-dominated delta-slope setting (Blackden Brook, North Derbyshire).
High-resolution sequence stratigraphy in the early Marsdenian (Namurian, Carboniferous) of the central Pennines and adjacent areas
Authors: Wignall Paul B. , Maynard James R.
Published: December 2009

The early Marsdenian (Namurian Series) Readycon Dean Formation of the Pennines and adjacent areas records a complex series of rapid, high-magnitude base-level changes during a short interval of the Pennine Basin’s history. Detailed correlation, using a rapidly evolving ammonoid fauna, enables the details of this complexity to be traced across the basin. Two major base-level rises (flooding events) are seen, one at the base of the Readycon Dean Formation, that led to the establishment of extensive, deep-water, marine shales of the Reticuloceras gracile (R
2a
1) Marine Band and the other that established the R. bilingue (R
2b
2) Marine Band across the region. At the base of this second major transgression is a radioactive, organic-rich dark grey shale (the Denshaw Horizon) that provides a useful marker band. The conditions of intense, basinal anoxia responsible for this horizon have also been observed in a similar basal transgressive shale from the overlying Yeadonian succession. It would appear that stagnation during initial transgression was a recurrent theme in the Pennine Basin’s history. Both marine incursions were followed by the progradation of a single distributary channel sandstone body during highstand conditions: the Readycon Dean Flags and Scotland Flags respectively.

Two major sequence boundaries or unconformities also occur in the study interval. The lower sequence boundary shows the development of a 25 m deep palaeo-valley partially infilled with thin beds of sandstone and siltstone of the new Howels Head Flags Member. The valley may have been the feeder channel of the Alum Crag Grits (a thick, turbidite sandstone lobe) but the incision mechanism is enigmatic. The upper sequence boundary is marked by a period of strong erosion (at least 80 m of incision can be demonstrated locally) throughout the basin and, towards the basin margin, substantial portions of the Readycon Dean Formation have been removed. A marked shallowing of facies is associated with this second sequence boundary and it is everywhere overlain by fluviodeltaic facies of the Pule Hill Grit Formation.
Reworked palynomorphs as provenance indicators in the Yeadonian of the Pennine Basin
Authors: McLean D. , Chisholm J. I.
Published: December 2009

The Lower and Upper Haslingden Flags may be differentiated from other Yeadonian strata in the Pennine Basin by their bulk lithology (‘green-facies’) and the reworked palynomorphs that they contain. These characteristics allow correlative finer-grained sedimentary rocks to be recognized where arenaceous lithologies have died out, and put some constraints on the possible provenance of the Haslingden Flags. The source area must have included outcrops of unmetamorphosed (i.e. extra-Caledonide) Lower Palaeozoic rocks and marine Devonian strata, and/or marine Devonian sediments containing reworked Lower Palaeozoic palynomorphs. Previous palaeocurrent studies indicate a western provenance for the Haslingden Flags. The new palynological data suggest that some sediment may have come directly from Avalonian Ordovician terranes: suitable source areas extend from the Wales-Brabant High (St George’s Land) towards Newfoundland. However, the reworked palynomorph material may have been supplied to the Pennine Basin via multiple phases of reworking, involving marine Devonian rocks to the west of St George’s Land.
Some dinoflagellate cysts from the Kimmeridge Clay Formation in North Yorkshire and Dorset, UK
Authors: Bailey David , Milner Paul , Varney Tim
Published: December 2009

Four new dinoflagellate cyst species are described;
Circulodinium copei
sp. nov.,
Rhynchodiniopsis martonense
sp. nov. and
Trichodinium piaseckii
sp. nov. are from the Kimmeridge Clay Formation of North Yorkshire (Kimmeridgian,
Pectinatites pectinatus
Zone), and
Senoniasphaera clavelli
sp. nov. is from the Kimmeridge Clay Formation (Kimmeridgian,
Aulacostephanous autissiodorensis
Zone) in Dorset, England. These taxa have potential for use as stratigraphic markers and have also been recorded from equivalent sediments in the North Sea, Mid-Norway and Barents Sea areas.
Marine ostracods in the Lower Carboniferous fluviatile Fell Sandstone Group: evidence for base level change and marine flooding of the central graben, Northumberland Basin
Authors: Turner Brian R. , Dewey Chris , Fordham Charles E.
Published: December 2009

Seven species of ostracod have been identified from the coarser, more silty laminae within a thin shaly siltstone interval within the Lower Carboniferous Fell Sandstone Group in the eastern part of the Northumberland Basin, all of which indicate a quiet, nearshore, shallow water marine environment. This is the first documented occurrence of marine ostracods from the Fell Sandstone which has always been regarded as entirely of non-marine origin, with any marine influences confined to the westernmost part of the basin. The shaly siltstone was proved in the Alnwick Borehole drilled through the upper section of the Fell Sandstone in an otherwise sandstone-dominated succession. The presence of marine influenced conditions more than 60 km inland from the coeval shoreline reflects contemporaneous intrabasinal tectonics and the location of the Alnwick Borehole at the northeastern end of the central graben within the Northumberland Basin. Marginal fault activity, contemporaneous with Fell Sandstone deposition, caused gentle tilting of the graben floor, thus allowing marine conditions to penetrate farther inland than previously known.

The ostracod-bearing marine shaly siltstone, which lies above and below braided river sandstones, provides a key sequence stratigraphic surface across this part of the basin. The base of the unit is a transgressive surface with the shale itself equivalent to a maximum flooding to truncated shale prone early high stand. The immediately overlying erosion surface records low stand incision, facies tract dislocation and the development of a possible sequence boundary, with the overlying stacked, cross-bedded, coarse pebbly braided channel sandbodies referred to the lower and middle parts of a transgressive systems tract that spans the boundary between the Fell Sandstone and succeeding, more marine influenced Scremerston Coal Group. The lower, finer-grained, fluvial succession beneath the transgressive surface is tentatively assigned to part of an incompletely exposed transgressive systems tract.
The Moorby Microgranite: a deformed high level intrusion of Ordovician age in the concealed Caledonian basement of Lincolnshire
Authors: Pharaoh T. C. , Allsop J. M. , Holliday D. W. , Merriman R. J. , Kimbell G. S. , Rundle C. C. , Brewer T. S. , Noble S. R. , Evans C. J.
Published: December 2009

A granophyric microgranite has been proved in the sub-Carboniferous basement at Moorby, near Horncastle in south Lincolnshire. The microgranite is interpreted as a high level intrusion which has suffered strong alteration and deformation subsequent to emplacement, including the development of a spaced pressure-solution foliation and brecciation. The microgranite has yielded a U-Pb zircon age of 457 ± 20 Ma (late Ordovician) interpreted as the age of emplacement. A Rb-Sr whole-rock isochron age of 400 ± 9 Ma (early Devonian) is strongly discordant with the U-Pb age, and is interpreted to reflect thorough post-emplacement hydrothermal disturbance of the Sr isotope system, either associated with the development of the tectonic foliation during the Acadian phase of the Caledonian Orogeny or subsequent uplift. Geochemical data suggest that the affinities of the Moorby Microgranite lie with the arc-related Ordovician intrusions of the Lake District (e.g. the Ennerdale and Eskdale plutons) rather than with the early Devonian high heat production (HHP) granites such as Shap, Skiddaw and Weardale. While the physical properties of the Moorby Microgranite are comparable to those of the HHP granites, gravity modelling suggests that the microgranite is unlikely to be a major component of the inferred Caledonide Wash - north Norfolk Batholith.
The Palaeozoic corals, II: structure, variation and palaeoecology
Authors: Scrutton Colin T.
Published: December 2009

Palaeozoic coral faunas were dominated by two orders of Zoantharian corals, the Rugosa and the Tabulata. Almost all rugose and tabulate corals developed an epitheca or holotheca around the corallum and possessed small to minute attachment scars. A limited number had an encrusting life style and many others could facultatively encrust to some extent when settling by chance on a hard substrate. However, most were effectively free living on a soft substrate as mature coralla. A high percentage of rugose corals were solitary and of the colonial genera, few exhibited physical integration of modules within the colony. In contrast, most of the exclusively modular tabulate corals possessed some degree of integration. Colony formation in tabulate corals was, with doubtful exceptions, solely by non-parricidal increase, whereas both non-parricidal and parricidal increase, the latter in a minor role, occur in the Rugosa. The sources of variation in solitary and colonial Palaeozoic corals are reviewed and data on growth rates, measured on the basis of cyclomorphic variation expressed as density band couplets, are assessed. Growth-form variation in solitary corals and its relationship to stability on the substrate are explored. Growth strategies in colonial corals are described and their adaptive success under different environmental conditions is discussed. Colonial growth-forms were a function of the interaction between growth strategy and prevailing conditions during astogeny, although some species had genetically constrained, relatively invariate growth-forms. Factors controlling the distribution of Palaeozoic corals in the environment–substrate and turbidity, water energy, depth, light, temperature and variations in salinity and oxygenation - are reviewed. Palaeozoic coral diversity was much lower than that of Recent hermatypic scleractinian corals in comparable environments. Most Palaeozoic corals were adapted to soft substrates in warm, shelf seas, and made a limited contribution to reef frameworks. It is concluded that none of them developed a symbiosis with algae in contrast to zooxanthellate scleractinian corals.
Palaeomagnetic dating of the west Cumbrian hematite deposits and implications for their mode of formation
Authors: Rowe John , Turner Peter , Burley Stuart
Published: December 2009

Palaeomagnetic analysis of six orientated hematite samples from the Florence Mine, Egremont, west Cumbria is described. A total of 21 specimens were subjected to incremental thermal demagnetization and the components of magnetization isolated by principal components analysis. All the specimens displayed a single component of magnetization with no evidence of either multicomponent magnetizations or significant low-temperature secondary magnetic components. The mean direction of the characteristic remanence based on the isolated components has a declination of 203°, and an inclination of −13° (α
95
= 10°,
k
= 12) with the corresponding pole position at 38.6°S, 333.5°E (
D
p
= 5.2,
D
m
= 10.3).

A single primary component is responsible for the characteristic remanent magnetism (ChRM) directions. The initial susceptibilities and magnetic intensities are compatible with petrographic observations that the samples comprise virtually pure hematite. The ChRM originated as chemical remanent magnetism when the hematite precipitated at temperatures over 100°C. Comparison of the calculated pole position for the west Cumbrian hematite deposits with the apparent polar wander path for Britain south of the Iapetus Suture reveals that the ore deposits formed during the Late Carboniferous and Early Permian.

The west Cumbrian hematite deposits therefore are not precipitates of a brine expelled from the Triassic sediments of the East Irish Sea Basin. The hematite may have precipitated from a brine expelled from older sediments (Devonian?), a fluid associated with igneous activity resulting from Permian rifting in the Irish Sea area, or they may be associated with ingress of surface-derived fluids during the Permian.
The identification of syn-depositionally-active structures in the coal-bearing Upper Carboniferous of Great Britain
Authors: Rippon J. H.
Published: December 2009

The Upper Carboniferous coalfields of Great Britain occupy various tectonic settings. Excellent data sets allow detailed analysis of any relationship between structure and the depositional patterns. Syn-depositional movement can be identified on a basin scale, and also at the scale of individual faults. However, with the exception of the Scottish Midland Valley, definitive evidence for syn-depositional movement on specific structures is relatively rare, and especially so in the English Pennine Basin. In particular, there is a general scarcity of detailed structural control on coal-depositional patterns. The environments in which coals formed would have been much more sensitive to subtle ground movements than the higher energy environments of the major channel belts. The precursor peats were widespread and commonly diachronous, and probably spanned around half the available time and space during Westphalian deposition across the Pennine Basin. The rarity of localized structural controls on coal patterns is therefore firm evidence of rarity of specific syn-depositional faulting throughout the sedimentary volume. Using mining data mainly from the Pennine Basin and the Midland Valley, this account discusses examples of likely, and less likely syn-depositional features, and proposes structural and sedimentological critieria for systematic assessment.
Distinction between detrital and volcanogenic clay-rich beds in Turonian–Coniacian chalks of eastern England
Authors: Wray David S. , Wood Christopher J.
Published: December 2009

The acid insoluble <2 μm fraction of 36 clay-rich marls, each from a stratigraphically distinct bed, in the Turonian and Coniacian chalks of Lincolnshire and East Yorkshire has been analysed. All beds are dominated by smectite, with traces of illite and sporadic trace amounts of kaolinite. Major, trace and rare-earth element whole rock data show that the clay-rich beds fall into two groups. The majority have a relatively constant K
2
O/A1
2
O
3
ratio (mean 0.12), low Zr/Al
2
O
3
ratio (mean 0.002) and variable TiO
2
/Al
2
O
3
ratio (mean 0.07); shale normalized rare-earth element (REE) data displays a negative Ce anomaly and a variable, gradual depletion in heavy REE. By analogy with clays in the German Chalk, these beds are considered to be detrital. Six beds (Barton 1, Melton Ross, Deepdale Lower, North Ormsby, Ulceby and Little Weighton 2) are characterized by a variable K
2
O/A1
2
O
3
ratio (mean 0.05), relatively high Zr/Al
2
O
3
ratio (mean 0.007) and low TiO
2
/Al
2
O
3
ratios (mean 0.03). Shale normalized REE data typically displays a slight negative Ce anomaly and a variable, but commonly marked, negative Eu anomaly. By analogy with German examples, these beds are interpreted as bentonites derived from the
in situ
alteration of volcanic tephra. Geochemical data indicate that tephra had a rhyolitic to pantelleritic composition. The occurrence of mid Turonian to mid Coniacian bentonites in the Chalk of eastern England provides the first evidence that clay-rich beds in the English Chalk have more than one origin.
An overview and update of the site characterization studies at Sellafield
Authors: Bowden R. A. , Bumpus C. , Littleboy A. K.
Published: December 2009

Nirex is responsible for providing and managing facilities for the safe disposal of intermediate-level and certain low-level radioactive waste. In 1991 Nirex chose an area near Sellafield, west Cumbria as the focus for further investigations, following preliminary geological investigations undertaken there and at Dounreay in Scotland from 1989. The Nirex Science Programme aimed to assess the suitability, or otherwise, of the Sellafield site as the host for a repository. Such an assessment included the requirement to develop an understanding of the geological and hydrogeological characteristics of the area. The background to the selection of the Sellafield area for site characterization for a potential radioactive waste repository and the early results from Nirex’s site investigations at Sellafield were reported to the Yorkshire Geological Society in October 1994. We present an update of the site characterization activities undertaken at Sellafield since then together with an overview of the advances in geological and hydrogeological understanding of the site resulting from those investigations.
Fluid flow in faults: a study of fault hydrogeology in Triassic sandstone and Ordovician volcaniclastic rocks at Sellafield, north-west England
Authors: Gutmanis J. C. , Lanyon G. W. , Wynn T. J. , Watson C. R.
Published: December 2009

The structure and hydrogeological properties of subsurface faults in the Triassic Sherwood Sandstone Group and Ordovician Borrowdale Volcanic Group at Sellafield in west Cumbria were investigated in order to develop conceptual and numerical models for input to groundwater flow modelling at the possible site of an underground radioactive waste repository. Eighteen borehole intersections of faults were studied using core, borehole imagery and hydraulic test data (single and multi-well testing). The results were integrated with data and interpretations from seismic surveys and field studies in order to prepare conceptualizations of fault architecture and hydrogeology, suitable for taking forward into numerical modelling. Hydraulic test data indicate that fault zones in the Sherwood Sandstone Group are slightly more permeable than the host rock, and geological observations suggest that flow may be focused in the fault damage zones rather than in the faultrocks, which tend to act as flow baffles. Where present in sufficient numbers, granulation seams appear to be flow inhibitors. In the volcanic rock, hydraulic test data indicate that fault zones have little permeability contrast with the host rock. However, geological observations suggest that minor reactivation may have locally disrupted the baffling effect of faultrocks, thereby creating ‘leak points’. Overall, the study suggests that ground-water flow in faults at Sellafield is highly heterogeneous at the borehole scale, but at larger scales the hydraulic behaviour of faults is more homogeneous.
Geotechnical characteristics of the Borrowdale Volcanic Group
Authors: Davies N. , Chaplow R.
Published: December 2009

As part of its investigations in the Longlands Farm area near Sellafield, west Cumbria, Nirex has generated a database of geotechnical information on the Borrowdale Volcanic Group rocks. Information has been obtained to depths of over 1000 m. The database was originally created to provide input to post-closure performance assessment studies for a potential radioactive waste repository. However, the information gathered is of generic value in understanding both the geotechnical characteristics of these deep rock units and the techniques available for their characterization. Information on the lithological characteristics of the rock units, the spatial properties of discontinuities, rock material properties,
in situ
stresses and rock mass properties has been collected from investigations including surface mapping, borehole core logging, borehole testing and geophysical surveys. The information has been compiled into a series of data sheets summarizing the characteristics of the identified rock units as a basis for subsequent modelling. Variations in rock mass properties, expressed as rock mass ratings, have been mapped in three dimensions using information obtained from boreholes and from regional geophysical surveys. The paper describes the studies undertaken and presents a summary of the results obtained.
Hydrogeological and geotechnical rock property characterization from geophysics
Authors: Brerton N. R. , Evans C. J. , Kingdon A.
Published: December 2009

Boreholes drilled at Sellafield penetrated a variety of rock units. Core samples and wireline logs indicate that rock mass properties and
in situ
fluid properties vary from one unit to another, but that properties are relatively uniform for each unit within a particular borehole. Variability is superimposed upon the bulk rock mass properties, however, where faults or zones of fractured rock intersect a borehole. Furthermore, lateral variability within a particular unit may be expected between boreholes and throughout the rock volume.

The primary objectives of the work were: to establish a means of determining the spatial heterogeneity and distribution of rock mass and fluid properties using measurements made on core samples and derived from wireline logs; to determine the spatial heterogeneity and distribution of rock mass properties away from boreholes and in three-dimensions, by extrapolating the detailed understanding gained from boreholes into the seismic survey volume; and to develop a visualization model of rock mass properties in three-dimensions.

It has been demonstrated that acoustic impedance is the principal property in common between surface seismic and borehole measurements, and that it provides a link between the various scales of measurement. Dynamic rock quality and hydrogeological indices have been developed which allow qualitative comparisons to be made between the boreholes. Empirical relationships have also been established between acoustic impedance and rock quality, and between acoustic impedance and hydrogeological properties. These relationships enable continuous profile quantitative estimations of Rock Mass Rating and hydraulic conductivity to be made from wireline logs, and have allowed these properties to be extrapolated into the seismic acoustic impedance volume, thereby providing three-dimensional visualizations of the spatial heterogeneity of rock mass properties.
The ‘Balladoole Coral’ from the Lower Carboniferous of the British Isles, reinterpreted as the unusual cystoporate bryozoan
Meekoporella
Moore & Dudley, 1944
Authors: Wyse Jackson Patrick N. , Taylor Paul D. , Tilsley John W.
Published: December 2009

Michelinia balladoolensis,
originally described by John Smith, in 1911, from the Lower Carboniferous of the Isle of Man, is an unusual fossil with a distinctive morphology. Smith regarded it as a tabulate coral, but subsequent workers have tentatively assigned it to the conulariids or to the Bryozoa. Restudy of the type specimens, together with material from the Asbian of Armagh, and newly collected specimens from the Bee Low Limestones (Asbian) of Derbyshire, demonstrates that
Michelinia balladoolensis
is a cystoporate bryozoan referable to
Meekoporella.
Specimens of
Meekoporella balladoolensis
comprise small inverted pyramids, open-ended and typically five-sided; compound colonies are constructed of clusters of contiguous pyramids. Colonies were apparently arboreal, living attached to crinoid stems or other cylindrical substrata which supported them some distance above the sediment surface in reefal settings. A lectotype and paralectotype are designated for
M. balladoolensis. Meekoporella bancrofti
sp. nov. is described from the Hotwells Limestone (early Brigantian) of the Mendips, and differs from
M. balladoolensis
in having smaller autozooecial apertures and reflexed autozooecial chambers.
Lithological and faunal stratigraphy of the Aptian and Albian (Lower Cretaceous) of the type Speeton Clay, Speeton, north-east England
Authors: Mitchell Simon F. , Underwood Charlie J.
Published: December 2009

Study of the Aptian and Albian parts of the Speeton Clay Formation at Speeton, North Yorkshire, has produced a detailed stratigraphy and a large collection of stratigraphically constrained fossils, despite the general poor state of exposure. This has allowed the development of a readily applicable bed numbering scheme and detailed faunal (macrofossil, foraminifera and ostracod) range charts. The Barremian-Aptian boundary is marked by the appearance of abundant examples of the ammonite
Prodeshayesites
and a marked lithological change from black shale to sandy mudstone. Higher parts of the Aptian have yielded abundant faunas, including ammonites of the
fissicostatus, forbesi
and
deshayesi
zones; the base of the
forbesi
Zone marked by the incoming of Ewaldi Marl facies. Poorly fossiliferous silty shales of the Albian
tardefurcata
Zone are succeeded by a bed with glauconite and phosphate pebbles, interpreted as marking the base of the
mammillatum
Superzone. This is overlain by fossiliferous clays of the Lower Albian and part of the Middle Albian. Range charts for macrofossils and microfossils from the Upper Barremian to Middle Albian of Speeton are constructed and biozones indicated. Aptian and Lower Albian successions inland of Speeton are highly variable, probably due to intra mid-Cretaceous fault movements. The same general stratigraphy as at Speeton, however, may be seen across much of the southern North Sea.
An epibiont and the functional morphology of the column of a platycrinitid crinoid
Authors: Donovan Stephen K. , Lewis David N.
Published: December 2009

The columns of the Upper Palaeozoic, monobathrid platycrinitid crinoids are generally considered to be highly flexible due to the presence of well developed synarthrial articulations. However, in some species these are modified to symplectial or syzygial articulations of unusual geometry. That the latter are essentially inflexible is suggested by a unique specimen from the Brigantian of Coverdale, Yorkshire, intimately encrusted during life by the tabulate coral
Cladochonus.
Such rigid articulations are associated with the attachment structure, giving these crinoids a particularly xenomorphic column with respect to articulation, despite a conservative external appearance which may lead to erroneous deductions concerning function.
Palaeocurrent direction and velocity in the Great/Main Limestone on the Alston and Askrigg blocks of northern England
Authors: Fairbairn R. A.
Published: December 2009

Productids, corals and crinoid stems have been used to determine the palaeocurrent direction and velocity in the ‘Fossil Posts’ of the Great/Main Limestone of the Alston and Askrigg Blocks. In Yorkshire the predominant current direction was from the south. In Teesdale and Weardale the current was from the south-east, becoming more from the east in the head of Weardale. The current velocity, as determined by the presence of orientated corals,
Latiproductus, Gigantoproductus
or crinoids, falls within the narrow range of 15 to 30 cm/s.
Correlation between the nannofossil and macrofossil biostratigraphies and the lithostratigraphy of the Upper Cretaceous of NE England
Authors: Burnett Jackie A. , Whitham Felix
Published: December 2009

To supplement the recent documentation of the stratigraphy of the Ferriby, Welton, Burnham and Flamborough Chalk formations by Whitham, a study of the nannofloras of this region was undertaken, allowing correlation between the lithostratigraphical units, the macrofossil zones and the recently revised standard nannofossil zonation scheme for the Upper Cretaceous. Attention is draw to the sequence of integrated nannofossil and macrofossil events around the stage boundaries, and some preliminary comparisons of the nannofossil events are made with those of southern England and northern Germany. It is suggested that further biostratigraphical work needs to be carried out through the Cenomanian/Turonian boundary interval, in order to determine the precise relationship between the nannofossil events and the boundary event. The view that the nannofossil
Marthasterites furcatus
is a suitable marker for the Turonian/Coniacian boundary is reiterated as being erroneous. Documentation of the nannofloras of NE England have proved them to have been influenced by a northern high-latitude (boreal) palaeobiogeographical setting during the Late Cretaceous.
Reconnaissance hydrogeochemical evaluation of an abandoned Pb – Zn orefield, Nent Valley, Cumbria, UK
Authors: Nuttall C. A. , Younger P. L.
Published: December 2009

The Nent Valley is underlain by cyclic successions of Carboniferous rocks unconformably resting upon Lower Palaeozoic basement rocks intruded by Lower Devonian granites. Mineralization of this sequence created a large, once productive ore-field. Two centuries of intense lead and zinc ore extraction have created over 90 adits in the Nent Valley, five of which presently discharge metal-rich water to the River Nent with serious consequences for the flora and fauna. High aquatic zinc concentrations are toxic to fish and cause a depletion in invertebrate food supply, consequently decreasing fish populations. Mine waters are rich in several ecotoxic metals (lead, zinc and cadmium). By computer modelling the speciation of these elements and the phases in which they occur it is hoped that a mechanism for the removal of metals as mineral phases can be devised. The effect of passing mine waters through an aerobic system such as a constructed wetland was modelled and no change in species distribution or mineral phase saturation was observed. Modelling showed that a small pH rise would remove zinc from the mine waters as the carbonate (smithsonite). If active treatment were considered, the mine waters could be diverted and treated together by making full use of the Nent Force Level, a feature that was created during the mining era.
Lower Carboniferous sponges from the Craven Reef Belt of North Yorkshire
Authors: Rigby J. Keith , Mundy D. J. C.
Published: December 2009

Fossil sponges are significant elements in framework facies of Late Visean Cracoean reefs of northern England. In the Craven Reef Belt (North Yorkshire), lithistid demosponges, including
Scheiia castletonense
(Wolfenden 1959),
Haplistion carbonaria
(Wolfenden 1959) and
Haplistion mega
sp. nov., occur along with the less abundant, sphinctozoid demosponge
Sollasia ramosa
sp. nov. in this facies.
Scheiia castletonense
is an irregular globose to mound-shaped tricranocladinid hindiid sponge with irregular secondary branchlike growths in which the canal and skeletal structure are continuous with those of the globular part of the sponge. Both species of
Haplistion
are rhizomorinid lithistid sponges.
Haplistion mega
is a lobate sponge characterized by moderately coarse skeletal tracts that are relatively far apart, in contrast to the fine tracts and closer spacing in the more common globose to subspherical
Haplistion carbonaria
. The aporate ‘sphinctozoan’
Sollasia ramosa,
commonly appears in the available sections as isolated spherical chambers because of its relatively loose branching habit and the beadlike to moniliform series of spherical chambers in each branch.
An outline of the lithostratigraphy and depositional history of Quaternary deposits in the Sellafield district, west Cumbria
Authors: Merritt J. W. , Auton C. A.
Published: December 2009

A lithostratigraphical framework has been erected for Quaternary deposits of the Sellafield district in west Cumbria. It has enabled a sequence of glacial and deglacial events to be established that is one of the most detailed for the last glacial-inter-glacial cycle onshore in Britain and provides new constraints on models of the evolution of the Irish Sea basin during the last 120 000 years. The products of at least one major pre-Devensian (Oxygen Isotope Stage 6 or older) glaciation have been recorded in cored boreholes around Drigg and Nether Wasdale. Ice flowing from Wasdale terminated in proglacial lakes on two occasions during OIS 3 and 4 and an intervening cold-water marine incursion occurred that reached a height of at least 20 m below present sea level, probably during OIS 3. Glaciers emerged again from the Lake District during the build-up of the main Late Devensian ice sheet, which appears to have reached its maximum extent early in OIS 2, when the whole district was glaciated. Scottish ice flowing into the northern Irish Sea basin eventually deflected local ice southwards. The Irish Sea ice stream became dominant again during several readvances that followed a significant deglacial event. The first readvance (Gosforth Oscillation) over-rode most of the coastal plain. The last major one (Scottish Readvance) proglacially tectonized the glacigenic sequence along the coast, forming a push moraine at St Bees. Thick sequences of glaciolacustrine sediment accumulated within the major valleys of the district, both before and after the Gosforth Oscillation, when ice at the coast caused considerable ponding of meltwater inland.
Devensian Lateglacial and early Holocene floral and faunal records from NE Northumberland
Authors: Jones R. L. , Keen D. H. , Robinson J. E.
Published: December 2009

Radiocarbon-dated Late Devensian and early Holocene pollen, molluscan and ostracod assemblages, from the sediments of an infilled kettle-hole lake near Wooler in north-eastern Northumberland, are described and discussed in both a local and a wider context. During the Lateglacial interstadial, open birch woodland developed for a short time after herbaceous vegetation had first dominated the surrounding landscape. Scrub was present for the remainder of the interstadial. Mollusca and Ostracoda immigrated into the lake during the pre-woodland phase of the interstadial, then disappeared, perhaps due to a climatic deterioration. A depauperate fauna returned in the latter part of the interstadial, when a less hostile aquatic environment may have existed. In the succeeding Loch Lomond Stadial, a periglacial climate led to tundra-like vegetation and to the extirpation once again of the lacustrine fauna. In the early Holocene,Betula-thenCorylus-dominated woodland was preceded by scrub and heath. Mollusca and Ostracoda recolonized the water body at the start of the Holocene, with the former quickly developing a diverse fauna. Two episodes of increased lake level with an intervening fall are suggested by the faunal assemblages. The second rise in water level was accompanied by vegetation changes in its environs, which may have been linked to a wetter and cooler climate than that which preceded it, and which occurred between 8000 and 7000 BP.
Emplacement of the Great Whin Dolerite Complex and the Little Whin Sill in relation to the structure of northern England
Authors: Johnson G. A. L. , Dunham K. C.
Published: December 2009

By definition, sills are concordant, tabular sheet-like bodies of igneous rock with the Great Whin Sill of northern England often quoted as a primary example. Analysis of surface and subsurface records of the Great Whin shows that it is seldom concordant over wide areas and usually rises and falls in the stratigraphical succession in gentle transgressions and abrupt jumps to new levels. The term ‘sill’ is not used here for the Great Whin complex, but is used for the related Little Whin Sill of Weardale, Co. Durham. Studies of the petrology of the dolerite Whin complex have brought out significant differences between the Little Whin and the Great Whin. The Little Whin Sill is olivine-bearing and believed to be composed of an early differentiate of the Whin dolerite magma. The Great Whin, non-olivine-bearing and slightly density graded, is a later differentiate of the Whin magma. Two separate periods of Whin dolerite injection are confirmed by studies of vitrinite reflectance over the Alston Block where two periods of Whin contact metamorphism have been recognized. The two periods of Whin dolerite emplacement form part of the end-Carboniferous earth movements in northern England. They can be shown to have occurred between a period of compression from a W-SW direction and later gentle doming of the Alston Block near the Westphalian-Stephanian boundary, dated about 300-295 Ma.