The Mercia Mudstone Group in the UK extends from the south coast to the Midlands where it bifurcates and continues through the North of England. The Mott MacDonald SYSTRA Design Joint Venture is working on behalf of Balfour Beatty VINCI, High Speed 2 (HS2) Limited's main works civils contractor for the West Midlands. BBV is constructing 90km of civils infrastructure to support the high speed railway between Long Itchington, in Warwickshire, the centre of Birmingham and on to Staffordshire. This crosses the Worcester/Knowle basins of the Mercia Mudstone Group. The Mercia Mudstone Group is known to possess a stratigraphy of varying lithologies within each geological formation. The HS2 project has gathered unprecedented quantities of geotechnical data on the Mercia Mudstone Group. By comparing this data with published literature, it has been highlighted how some geotechnical properties for engineering design vary by formation. A review of the SPT N-undrained shear strength correlation has also been undertaken, which has shown the potential for high variability in the f 1 factor. From this comparison with literature, the geotechnical parameters interpreted from the HS2 ground investigation appear to be representative of the Mercia Mudstone Group in other parts of the UK.
A recently rediscovered manuscript of William Turner's 1793 essay on 'Terra Ponderosa' provides a remarkable contemporary account addressing confusion over the type locality for the newly described mineral witherite, the key question being whether or not witherite was known from Alston Moor at the time. Turner's essay corroborates a recent reaffirmation that the type material came from Anglezarke, near Chorley in Lancashire, rather than Alston Moor. Turner's manuscript provides a description of unpublished experiments conducted in 1782 by William Irvine, Professor of Chemistry at Glasgow University, on 'native aerated Terra Ponderosa' from Leadhills, later misattributed in chemistry texts as having been found by Withering. It also indicates that John Smeaton, formerly a co-receiver of the Greenwich Hospital (holder of the mineral rights) for the Alston Moor mines, had supplied the type material studied by Withering, his earlier association with Alston Moor possibly contributing to the initial misattribution of the type locality.
A lateral variation in the heterolithic platform facies is present on the southern flank of the Askrigg Block where it transitions to mudrock-dominated basinal facies of the Craven Basin during the Brigantian substage. Revised geological mapping and new micropalaeontological assessment are used to correlate Transition Zone strata with the mixed carbonate and deltaic (Yoredale) cyclic facies of the Alston Formation of the Askrigg Block. This shows the Hawes Limestone to be entirely early Brigantian in age, with a consistent thickness across the study area. The overlying Gayle and Hardraw Scar cycles show marked variations consistent with displacement on the North Craven Fault, whereas the subsequent Simonstone and Middle Limestone cycles are absent within the Transition Zone. The Transition Zone includes younger Brigantian strata than found on the southern Askrigg Block. The Transition Zone is demonstrated to be: (1) affected by early Brigantian regional extension leading to transtensional oblique-slip displacement on the North Craven Fault and northward tilting of the Askrigg Block; (2) development of an erosive palaeo-slope in the Transition Zone during the early to late Brigantian extending across the North Craven Fault in response to transpressional structural inversion, uplift and erosion; (3) onlap of the late Brigantian Alston Formation and subsequently Bowland Shale Formation onto the incised Alston Formation during post-rift regional subsidence; and (4) ultimate northward tilting of the Askrigg Block during the early Pendleian in response to transpressional oblique-slip on the North Craven Fault, prior to deposition of the Millstone Grit Group.
At York Castle, in March 1837, Joseph Thackwray, the owner of Harrogate's Crown Hotel, appeared before the Spring Assizes charged with digging a well in the immediate vicinity of a public supply of spa waters (The Old Sulfur Well) that formed a vital part of the local economy, reducing its yield. Both plaintiffs and the defendant fielded an array of distinguished witnesses, which included William Smith and John Phillips, whose statements centred around the question of whether Harrogate's mineral springs arose from a common source or if each spring arose independently. Their statements provide a snapshot of contemporary views on the geology and origin of the waters but have been largely ignored by subsequent workers. Following an opening address by the plaintiff's counsel, discussions with the judge resulted in a compromise without any of the witnesses being called to give evidence. Thackwray was found not guilty and an agreement was reached to share the water from his new well. Why the plaintiffs accepted the compromise is unclear as any gains they made were largely illusory whereas abstraction from Thackwray's wells remained unrestricted. Subsequent research has supported a common source for the springs although this is far from the 'common subterraneous cavern or reservoir' postulated by the plaintiff's counsel.
Radio-carbon dating of southern Shap Fells post-glacial deposits constrains periods of mid-Holocene subepoch hillslope erosion and the development of blanket peat. An organic-flecked blue solifluction clay was deposited between 5327 and 5272 cal BP, at the end of a cool climatic interval. Organic-rich silt sapropel was preserved within rock hollows at altitudes between 456 and 462 m asl from 5762 to 5651 cal BP, with blanket peat on level terrain at similar altitudes developing around 3350 to 3165 cal BP, i.e. within the Bronze Age. Despite a warmer and wetter climate at this time, at lower altitudes peat development was inhibited on steep unstable slopes. Instead, slope-washed grey silt was deposited on the blue clay initially between 2435 and 2309 cal BP, after which slope instability led to inter-bedding of silt and peat. Variable dates for peat initiation likely reflect local differences in nutrient and slope stability status, rather than climatic controls alone. Pollen records show a decline in woody heath as herbaceous grassland developed. Charcoal may indicate burning of shrub and tree cover during the Bronze Age to extend open high-level pasture for graziers. Partial woodland recovery was localized and may relate to a contraction in regional agricultural activity during the Iron Age.
Upper Triassic to lowermost Jurassic strata in eastern and northeastern England are poorly exposed with the result that environmental changes during the associated end-Triassic mass extinction (ETME) interval have not been fully evaluated in the region. Here, we report on two records: an offshore, mudrock-dominated section at Bantycock Quarry in Nottinghamshire, and a sandstone-rich succession from the Dove's Nest borehole from the Cleveland Basin, North Yorkshire. The latter provides an expanded record and has a complete organic carbon isotope stratigraphy comparable to that seen elsewhere in the British Isles. The Westbury Formation at Dove's Nest is unusually dominated by bioturbated sandstones, whilst more typical offshore, dark-grey mudstones are seen at Bantycock Quarry. A sequence boundary marks the transition to pale-grey mudstones of the Cotham Member, and the loss of marine fauna in the basal centimetres records the level of the first phase of the ETME. These losses coincide with the development of freshwater conditions. The return of marine conditions higher in the Cotham Member is marked by flooding and a major negative carbon isotope excursion. Contrary to previous reports, the Langport Member is well developed in the Cleveland Basin where it is manifest as a dark-grey mudstone with thin storm-generated sandstones. At Bantycock Quarry, erosion has removed most of the Langport Member, although thin limestone conglomerate lenses at the base of the Blue Lias have likely derived their clasts from erosion of the White Lias (a unit characteristic of more southerly outcrops in England). The major sequence boundary at the base of the Blue Lias at Bantycock is attributed to local tectonic uplift, because there is no evidence for base-level fall in the more northern Cleveland Basin. The second phase of the ETME occurs at the top of the Langport Member, and as with the first phase this is associated with a negative carbon isotope excursion. This level is overlain by anoxic facies indicating oxygen deficiency played a role in the second extinction phase.
Pollen analysis and radiocarbon dating of a sedimentary sequence from mid-Teesdale, in the north Pennines of northern England, are reported. Organic sedimentation began before the start of the Lateglacial Interstadial above a clastic unit that had accumulated since local ice retreat. The lithology does not contain a mid-profile clastic unit typical of sedimentation during the Lateglacial Loch Lomond Stadial which, supported by an anomalously old date in the age-depth sequence, indicates a depositional hiatus, probably caused by permanent freezing of the water body during that severely cold phase. Other radiocarbon dates form a smooth age-depth curve for a pollen record extending from the Lateglacial Interstadial's start until soon after the mid-Holocene Elm Decline. The vegetation history is analogous to that at other sites in upper Teesdale and at higher altitude sites in the Pennines generally, although Holocene woodland was less open than at the highest altitude sites. Radiocarbon ages for pollen zone boundaries are similar to those at high altitude sites, but significantly later than the dates for these boundaries at regional lowland sites. There are no indications of pre-Elm ( Ulmus ) Decline, Late Mesolithic-age woodland disturbance. Low-scale woodland opening occurs at and after the Elm Decline in the early Neolithic period.
An erratic chert pebble discovered on an exposure of the Lowestoft Till (Anglian Stage, Pleistocene) of North Lopham, Norfolk, UK, contains graptolites preserved three-dimensionally in silica in a mode not known in the UK. The graptolites are Monograptus parapriodon , Monograptus priodon , Monoclimacis linnarssoni and an undetermined retiolitid that indicate an Oktavites spiralis Biozone (mid-late Telychian, Late Llandovery, Silurian) age. The graptolites are associated with organic-walled microfossils, some containing internal bodies. The combination of lithology, preservation and low thermal maturity seem to exclude a British origin. The closest comparison is with Silurian chert pebbles in Miocene and Pleistocene gravels in central Germany, thought to be derived from bedrock in the Frankenwald region of Thuringia. A conjectured natural transport vector for this pebble involves drainage along the proto-Rhine system flowing into early/mid Pleistocene North Sea deltaic/marine deposits, with subsequent glacial transport to Norfolk. The possibility of an anthropogenic vector is also considered, but dismissed.
Detailed stratigraphic sections recorded by the mining industry in Great Britain were first published during the eighteenth century. In the northern Pennines, Forster presented the first representative long composite stratigraphic section in 1809. It encompassed the entire known Carboniferous (as it was later named) succession, with the portion representing the lead mining district summarizing 'a sequence worked out during many centuries of lead mining'. Three other shorter sections, also compiled from mining industry data and dating to between 1785 and 1800, had been published previously, with limited circulation. While the lateral continuity of the geology results in a broad similarity across all of the early sections, same-scale comparison combined with contemporary accounts constrains locations of the source data. A recent assertion that an unpublished composite section presented by Walton in 1793 to the Literary and Philosophical Society of Newcastle upon Tyne was the first 'stratigraphical section of the lead mining districts' with 'Hutchinson, Millar and then Forster later using his work without acknowledgement' is shown to be incorrect. The interest of Sir Joseph Banks in the emergence of stratigraphic geology in this period suggests that he may have been the enigmatic 'A Constant Reader' who corresponded on the topic of these early sections in the Philosophical Magazine. Forster's 1809 publication was the first concise synthesis of the Pennines Carboniferous, making 'the miners' succession' more widely accessible and providing a basis for later work.
Five Lower Albian (Lower Cretaceous) areoligeracean dinoflagellate cyst species are present in the Carstone Formation at Middlegate Quarry, North Lincolnshire, UK: Canninginopsis monile, Circulodinium deflandrei, Cyclonephelium compactum, Cyclonephelium intonsum and Cyclonephelium longispinatum. The taxonomy of Circulodinium deflandrei is reviewed with respect to 20 measured Carstone specimens. The taxonomy of Cyclonephelium longispinatum is reviewed with respect to 70 measured Carstone specimens and a study of 40 measured specimens from its type material in Site 361, Deep Sea Drilling Project Leg 40, offshore southwestern Africa. Circulodinium deflandrei and Cyclonephelium longispinatum have recently been considered by other workers to be junior synonyms, respectively, of Circulodinium hirtellum and Tenua anaphrissa. However, following detailed study of their morphologies, the synonymies are formally rejected here. An emended diagnosis is given for C. longispinatum. A re-assessment of the stratigraphical ranges of taxa co-occurring with the type material of C. longispinatum is consistent with a Late Albian to Early Turonian age range in Site 361.
Ankylosaurs are a characteristic group of dinosaurs recognized by their extensive coverings of dermal bony armour, known as osteoderms, across their bodies. The Oxford Clay Formation (Callovian–Oxfordian, Middle Jurassic) in the UK is important for understanding early ankylosaur evolution as it contains some of the earliest known ankylosaur material, including a cranial osteoderm from the basal-most ankylosaur Sarcolestes (and probable postcranial osteoderms). Here, we describe an isolated osteoderm from the Oxford Clay of Peterborough that exhibits a different morphology to other osteoderms from this formation. The specimen, although incomplete along its transverse axis, measures 52.7 mm by 41 mm. The osteoderm is subrectangular with a concave ventral surface and a low, rounded keel on its dorsal surface that protrudes beyond the posterior margin of the specimen base. This morphology is superficially more similar to the thoracic osteoderms of more derived Cretaceous ankylosaurs from North America (e.g. Borealopelta ), than to Sarcolestes and other Jurassic ankylosaurs (e.g. Dracopelta , Mymoorapelta , Tianchisaurus ), but could represent a currently unknown Sarcolestes morphology. Although its isolated nature prevents reliable identification of the taxon and the body part to which it belonged, the osteoderm nevertheless indicates a larger morphological diversity in the body armour of the earliest ankylosaurs than currently appreciated.
George Tate, draper, postmaster and insurance agent, was not only a renowned civic figure during the mid-nineteenth century in his home town of Alnwick but was also, despite limited schooling, a widely celebrated and influential writer on the geology, biology, archaeology and history of Northumberland and adjacent parts of Scotland. His principal geological interests were wide ranging but in the main were devoted to the stratigraphy and palaeontology of the lower part of the Carboniferous System in his local area. Some of the lithostratigraphical terminology he proposed remained in use into the 1950s and, despite changes in nomenclature, elements of his classification can still be recognized in the modern lithostratigraphy. He put forward much evidence for the intrusive origin of the Whin Sill when it was still regarded by many of his contemporaries as a lava flow. Tate was among the first to describe and discuss the evidence in Northumberland and SE Scotland for the then novel idea that Britain had been subjected to the influence of ice in the recent geological past. His brother and two of his sons attended Edinburgh University and had distinguished professional careers. His nephew, Ralph, inherited much of his uncle's wide interests and became a highly celebrated figure in the development of geology in Australia.
Foraminiferal diversity and taxa richness from beds transitional between the Asbian and Brigantian substages (Middle Mississippian) show patterns of secular change which allow detailed inter-regional correlations to be established. Foraminifera from the Askrigg Block, Stainmore Trough, Alston Block, South Cumbria Shelf and Solway Basin show similar secular changes (foraminiferal trends, FTs), allowing correlation to be made with the basal Brigantian Stratotype at Janny Wood. Despite the absence of consistent microfossil first occurrence markers for the recognition of the base of the Brigantian, this horizon can be confidently recognized by means of foraminiferal trends. The FTs allow the precise location of the base of the correlated Brigantian in sections where this boundary was questioned or controversial in previous studies, as well as to amend the position of the foraminiferal zones and subzones during the late Asbian and basal Brigantian. This type of analysis when used in combination with foraminiferal zonations, emergent surfaces and lithological cyclicity, together, provide a robust means for high-resolution correlation. This methodology, provides the least uncertainty in sections that have been most densely sampled, whereas for less intensely sampled sections there is more correlation uncertainty.
Among the important geological attributes of the small Cumbraes Basin in the southwestern off-shore Midland Valley of Scotland, the 4 km-long, fragmented but well-exposed section through the Devonian–Carboniferous boundary sequence in southern Great Cumbrae island ranks highly. In a continuous short stretch of the south and west coasts, large portions of this sequence are superbly preserved in tide-washed strandline surfaces and in old post-glacial sea cliff. This enhanced exposure leaves no doubt that the outcrops belong to two, immediately successive, members of the Kinnesswood Formation – the lower the Doughend Sandstone, the upper the Foul Port Mudstone – and that they provide some of the best available exposures on which to base description and interpretation. The facies of the fluviatile Doughend Sandstone shares many characteristics with the underlying Kelly Burn Sandstone of the Upper Old Red Sandstone, whereas that of the Foul Port Mudstone is distinct and unusual, attributed to local tectonics, influenced by movements on older and more major fractures such as the Highland Boundary Fault, with sediment accumulation taking place in a playa-lake complex of considerable extent.
The early Marsdenian substage (Millstone Grit Group) of the Pennines comprises repeated deltaic cycles separated by ammonoid-bearing marine bands. This cyclicity, controlled by the combined forces of glacio-eustasy and modulations in sediment supply, provides an important outcrop area for the application of sequence stratigraphic principles. A new correlation framework is presented where two orders of sequence are identified: (1) a low-order sequence, within which marine bands (R 2a 1, R 2b 1, R 2b 2 and R 2b 3) represent a maximum flooding surface, and (2) high-order sequences nested within the low-order sequences. By integrating and correlating key exposures, historic well boreholes and field mapping, lateral changes in facies and facies association are observed, and palaeogeographic trends mapped. This allows the variation in sequence and systems tract stacking patterns to be interpreted. Three orders of Milankovitch cyclicity are inferred to control the sequence stacking patterns; long-duration ( c. 400 ka) eccentricity oscillation controlling maximum flooding events represented by the R 2a 1 and R 2b 2 marine bands, sub-100 ka obliquity oscillations (controlling the R 2b 1, R 2b 2 and R 2b 3 marine bands and intervening low-order sequence boundaries), and precessional frequencies ( c. 25 ka) which may control the periodicity of the high-order sequences. Supplementary material: Locality details, including lithostratigraphic units observed, gross and sand thicknesses within sequences, and palaeocurrent data measured are available at https://doi.org/10.6084/m9.figshare.c.6408203
A new specimen of a rare large theropod dinosaur print of Middle Jurassic age is described from the Long Nab Member of the Scalby Formation, Cleveland Basin, Yorkshire. This is only the sixth specimen of this type recorded from the Cleveland Basin since they were first discovered in 1934. The present specimen is included in the same, but slightly modified morphotype Bxviii as some of the previous ones, since it shows additional features including an elongated metapodium. The specimen is assigned to the ichnogenus Megalosauripus, and was possibly made by a Megalosaurus-like theropod. The elongated metapodium may be the result of resting or crouching behaviour.
Re-examination of the Langness Conglomerate Formation (LCF) on the coast near Dreswick Harbour, Isle of Man, has established that it is over 65 m thick, twice previous estimates. It formed as a small stream-dominated fan deposit during syndepositional faulting which controlled thickness and facies variations. The sub-Carboniferous surface shows considerable relief, perhaps as much as 10 m and is intricately brecciated and channelled just beneath the base of the conglomerate indicating a pluvial climate even prior to deposition of the LCF. Palaeocurrent data shows that sediment was derived from the NNW. Low in the LCF the sediment is all local in origin, but more exotic material is present higher up. The succession matures texturally (sorting and rounding improve) and mineralogically (lithic sand decreases) upwards and the succession fines upwards. The finer, upper part onlaps northwards across the older Manx Group extending for over 4 km inland thinning to 8 metres. This is consistent with the view that the Isle of Man formed a regional high during the Lower Carboniferous. The LCF resulted from the initial fault movements that led to inundation of the Isle of Man High in the late Chadian to early Arundian.
This paper re-introduces a forgotten subject, cannel coal, formed within very low gradient mire drainage systems. A minute part of the British Carboniferous rock volume, cannel was prized in the early Industrial Revolution for oil and gas, notably hydrogen. In this paper it is revisited to reveal under-reported palaeogeography, using modern mining and drilling data to give regional depositional insights. The focus is on the English East Midlands, in the SE of the Pennine Basin. Early literature on other areas emphasized deposition in small lakes, assuming little connectivity. In the East Midlands, large lake deposits are connected by cannel-filled channels, from the basin's southern margins up to 100 km north into Yorkshire. Interplays with fluvio-clastic systems are spread over a subtle but simple palaeoslope, north and NE to the Gainsborough Trough sub-basin, with negligible structural disturbance during deposition of the Pennine Coal Measures Group. A gentle basement tilt is indicated. Mire drainage tangential to the central basin invites discussion on wider issues, including marine flooding into the basin. Mire longevity is discussed, this also being relevant to research on contaminant contents through coal-forming times.
Here, we describe the upper Pliensbachian to middle Toarcian stratigraphy of the Dove's Nest borehole, which was drilled near Whitby, North Yorkshire, in 2013. The core represents a single, continuous vertical section through unweathered, immature Lower Jurassic sedimentary rocks. The thickness of the Lias Group formations in the Dove's Nest core is approximately the same as that exposed along the North Yorkshire coast between Hawsker Bottoms and Whitby. The studied succession consists of epeiric-neritic sediments and comprises cross-laminated very fine sandstones, (oolitic) ironstones, and argillaceous mudstones. Dark argillaceous mudstone is the dominant lithology. These sediments were deposited in the Cleveland Basin, a more subsident area of an epeiric sea, the Laurasian Sea. We present a set of geochemical data that includes organic carbon isotope ratios ( δ 13 C org ) and total organic carbon (TOC). The δ 13 C org record contains a negative excursion across the Pliensbachian–Toarcian boundary and another in the lower Toarcian that corresponds to the Toarcian Oceanic Anoxic Event (T-OAE). Below the T-OAE negative excursion, δ 13 C org values are less 13 C-depleted than above it. We find no evidence of a long-term δ 13 C org positive excursion. TOC values below the T-OAE negative excursion are lower than above it. Sedimentary evidence suggests that, during much of the Pliensbachian–Toarcian interval, the seafloor of the Cleveland Basin was above storm wave-base and that storm-driven bottom currents were responsible for much sediment erosion, transport, and redeposition during the interval of oceanic anoxia. The abrupt shifts observed in the δ 13 C org record (lower Toarcian) are likely to reflect the impact of erosion by storms on the morphology of the δ 13 C record of the T-OAE. Supplementary material: stratigraphic and geochemical data [organic carbon isotope ratios ( δ 13 C org ) and total organic carbon (TOC)] are available at https://doi.org/10.6084/m9.figshare.c.6154436
