Central Britain Research Articles

Large-scale climatic influences on precipitation and discharge for a British river basin

This article aims to identify the large-scale climate variables that yield significant statistical relationships with precipitation and discharge for a British river basin (Dyfi). Ranked correlation analysis was performed between gridded ERA-40 atmospheric data and Dyfi precipitation and discharge for individual months. Precipitation and discharge demonstrate significant negative correlation with mean sea level pressure (MSLP). Strongest MSLP correlation areas move from north of Britain in winter to central Britain in summer; this shift is associated with a displacement of geopotential (Z) and zonal wind (U). Movement of significant correlation regions (not captured by the North Atlantic Oscillation Index) highlights the dynamic nature of precipitation and river flow generating weather systems throughout the year. Existence of strong significant correlation shows potential for exploiting large-scale climate variables in forecasting precipitation and river flow in Britain. Copyright © 2010 John Wiley & Sons, Ltd.

Predicting range overlap in two closely related species of spiders

Abstract. Predicting when and where species are likely to experience inter‐specific interactions as a result of climate change may be as relevant to understanding their evolutionary futures as predicting responses to physical environmental variables. In this paper, models built using data for the distributions of two species of large house spider, Tegenaria saeva and T. gigantea (Agelenidae), from relatively long‐established parts of their ranges are used to predict species overlap in a region of more recent range expansion. Generalised linear models (GLMs) are used to identify the key environmental variables associated with the distributions of the spider species in an east–west band across central Britain. Using this model, the distributions of the two species both north and south of the central band are predicted and tested for how closely they matched observed distributions, and thus whether environmental factors are a sufficient explanation for current distribution patterns in England and Wales. Results demonstrate that predictions of both species distributions and overlap in the south region are almost as good as in the model‐building zone, but that predicted distributions in the north are no better than random. Here either climate is of no importance in determining species distributions or, perhaps more likely, the system is still in a state of flux and currently reflects the stochasticity of recent colonisation. Further long‐term monitoring of the populations may allow discrimination between alternative hypotheses that could explain the current mismatch between climate and species’ distributions.

BURNT KIMMERIDGIAN SHALE AT EARLY ROMAN SILCHESTER, SOUTH‐EAST ENGLAND, AND THE ROMAN POOLE–PURBECK COMPLEX‐AGGLOMERATED GEOMATERIALS INDUSTRY

Summary. A wide range of geomaterials were worked at industrial settlements scattered over an area of c.225 km2 in the Poole Harbour–Isle of Purbeck district of modern Dorset. These materials, more than one handled at some sites, included shale (‘coal’), burnt shales (yellow, red) and cementstones from the Kimmeridge Clay Formation (Upper Jurassic), Purbeck marble from the Purbeck Group (earliest Cretaceous), hard chalk from the Chalk Group (Upper Cretaceous), and potting clays and sands from the Bracklesham Group (Palaeogene), for South‐east Dorset Black‐burnished Pottery Category 1. There was also a salt industry, which could have used pottery for packaging. The industrial products are conterminously distributed in southern and central Britain and, in the case of pottery and shale items, reached as far as the northern frontiers. Raw material of red burnt shale was exported to Silchester (Calleva Atrebatum), where it was made into mosaic tesserae. Of proven Kimmeridgian age on the evidence of fossils, the mudstone used to make it had been collected and quarried on the coast of the Isle of Purbeck before being burnt. The decline in the demand for stone products, excepting shale, in the second century AD saw an expansion of the potting industry, which persisted into the fifth century. The term complex‐agglomerative is introduced to describe this diverse and dispersed enterprise at this highest hierarchical level, examples of which occur elsewhere in the Roman world.

Envionmental applications of airborne radiometric surveys

Airborne gamma-ray measurements, primarily developed for uranium exploration (e.g. Bristow 1983), have many applications in environmental monitoring and geological mapping (e.g. IAEA 1991; Jaques et al.1997; Wilford et al. 1997). For example, they have been used to map radioactive fallout from nuclear accidents (e.g. Mellander 1989) and contaminant plumes from power plants (e.g. Rangelov et al. 1993) as well as monitoring the impact of uranium mining. Airborne measurements can be used for quick and effective mapping of large areas. Although the gamma-ray measurements record variations in the radioactivity of a relatively shallow surface layer (c. 0.3 m), the results are useful for both regional and targeted surveys. The results are normally presented as total gamma activity and as equivalent ground concentrations of uranium, thorium, potassium and other radionuclides (e.g. 137Cs) or as ratios (including ternary K, U, Th plots). Methods have been developed to separate natural and man-made radioactivity. This paper presents some examples of environmental applications of airborne gamma-ray surveys from Germany and the UK. In both cases, the results of multisensor (radiometric, electromagnetic and magnetic) airborne surveys are validated by ground measurements and sampling. The AERA project (Assessment of environmental risks by airborne geophysical techniques validated by geophysical field measurements) was an EC-funded project in south-east Germany, coordinated by the Geological Survey of Finland (GTK) (Gaál et al. 2001). A 1100 km2 site in the Zwickau area of Saxony was selected because of its extensive mining and industrial activities over several centuries. Uranium, black coal and nickel mining and smelting, military activities, modern heavy industry, and industrial and domestic waste have caused considerable environmental impacts. The HiRES-1 survey of central Britain was carried out to assess a range of environmental and resource applications of airborne survey data. The 14000 km2 area surveyed encompasses a wide range of rock and soil types. The area includes many urban centres and has a long history of extractive and manufacturing industry. There are regions with relatively high indoor radon levels and areas contaminated by fallout from nuclear weapons testing, the Chernobyl accident and discharges from the Sellafield nuclear fuel reprocessing plant. Small targets within the HiRES-1 area were flown as part of a collaborative GTK-BGS (British Geological Survey) project to investigate specific sites in more detail. These included landfills, colliery spoil heaps and gravel workings used for power station fly ash disposal. Although a multisensor approach was adopted for these projects, this paper concentrates on the environmental applications of airborne gamma-ray data.

The Late‐glacial reoccupation of the British Isles and the Creswellian

AbstractThis paper presents a review of AMS radiocarbon dating evidence for human occupation of Britain during the Late‐glacial Interstadial. The dates are all on humanly modified materials, including artefacts, and on human bone. The CalPal program is used to test whether the earliest evidence of human presence shows any correlation with more widespread climatic events, and if the British chronology differs significantly from that of neighbouring regions of northwest Europe. In the second part of the paper a number of well‐dated sites with British Late Upper Palaeolithic ‘Creswellian’ technology are examined and compared with lithic assemblages from The Netherlands and Belgium. The main conclusions of this work are that expansion of human populations into the northern edge of the upland zone just before or at the beginning of GI‐1 was followed by repopulation of the British Isles possibly with very little time‐lag. The British Creswellian sites offer evidence of this earliest resettlement, which is mainly focused on the upland margins of western and central Britain. Copyright © 2003 John Wiley & Sons, Ltd.

Uniquely extensive seismite from the latest Triassic of the United Kingdom: Evidence for bolide impact?

Research Article| June 01, 2003 Uniquely extensive seismite from the latest Triassic of the United Kingdom: Evidence for bolide impact? Michael J. Simms Michael J. Simms 1Department of Geology, Ulster Museum, National Museums & Galleries of Northern Ireland, Botanic Gardens, Belfast BT9 5AB, Northern Irel Search for other works by this author on: GSW Google Scholar Geology (2003) 31 (6): 557–560. https://doi.org/10.1130/0091-7613(2003)031<0557:UESFTL>2.0.CO;2 Article history received: 28 Nov 2002 rev-recd: 07 Mar 2003 accepted: 10 Mar 2003 first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Michael J. Simms; Uniquely extensive seismite from the latest Triassic of the United Kingdom: Evidence for bolide impact?. Geology 2003;; 31 (6): 557–560. doi: https://doi.org/10.1130/0091-7613(2003)031<0557:UESFTL>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract A 2–4 m thick seismite, in places overlain by a previously unreported tsunamite, can be traced across >250,000 km2 of the outcrop and subcrop of the latest Triassic (Rhaetian) Cotham Member of the Penarth Group, United Kingdom, an extent unique for the British Phanerozoic. Its consistent thickness, intensity of deformation, and preferred orientations of slump-fold axes indicate a seismic event of M > 10 with an epicenter >600 km W or NW of central Britain. The magnitude of the event is incompatible with known terrestrial mechanisms (fault, volcano) but is consistent with a major bolide impact. A short, but unknown, interval separates the top of the Cotham Member seismite from major geochemical and biotic perturbations associated with the end-Triassic extinction, although a direct link between the seismite and these other events remains equivocal. The exceptional extent of “mega-seismites” such as this may prove a useful indicator of previously undocumented bolide impacts. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

From introduced species to invader: what determines variation in the success ofCodium fragile ssp.tomentosoides (Chlorophyta) in the North Atlantic Ocean?

The green algaCodium fragile ssp.tomentosoides (Chlorophyta) has been introduced accidentally and successfully from Japan to many shores of the northern and southern hemispheres, including those of the Northeast and Northwest Atlantic Ocean. On most European coasts,Codium occurs regularly but at low abundances in the intertidal zone and is absent from subtidal habitats. In contrast,Codium is extremely abundant in subtidal kelp beds in the Northwest Atlantic Ocean where it often reaches nuisance proportions. This differential success cannot be accounted for by either the properties of the invader or by physico-chemical differences between invaded coasts. A theoretical comparison between two regions on opposite sides of the Atlantic Ocean, i.e. Eastern Nova Scotia, Canada, and south central Britain, illustrates how the resident benthic community may determine the difference in relative abundance ofCodium in subtidal habitats between northeast America and Europe. In this review, low floral species diversity, biological disturbance and facilitation by a previous species invasion are suggested as potential factors for the establishment, success and abundance ofCodium in the Northwest Atlantic Ocean, but these require testing in field experiments.

Proto-Kimbe: A New Analysis

Using data gathered by Chowning, Valentine, and Goodenough in 1954, a reconstruction is undertaken of Proto-Kimbe, an Austronesian group of languages in North Central New Britain. It significantly revises the reconstruction by Johnston (1982). It confirms that Bali and Vitu, included by Johnston, must be excluded from the Kimbe group, though remaining closely related to it. This analysis shows that both the Kimbe languages and Bali and Vitu have had complicated histories, involving extensive borrowing from another Austronesian language by Bali and the merging of two dialect communities in the formation of what became Proto-Kimbe. This analysis also provides evidence that Proto-Malayo-Polynesian *p and *b had not merged in Proto-Oceanic as *p nor had *d and *D merged as Proto-Oceanic *r, as has been hitherto assumed, although such merger is widely attested in many Oceanic languages

Stable isotopic compositions of Recent freshwater cyanobacterial carbonates from the British Isles: local and regional environmental controls

ABSTRACTRecent (&lt;50 years old) freshwater cyanobacterial carbonates from diverse environments (streams, lakes, waterfalls) throughout Britain and Ireland were analysed for their stable carbon and oxygen isotope compositions. The mean δ18O value of −5–9‰ PDB for river and stream data represents calcite precipitation in equilibrium with the mean oxygen isotopic composition of precipitation in central Britain (−7–5‰SMOW) assuming a mean water temperature of 9°C. The mean δ18O of lake data, −4–5‰ PDB, is statistically different, reflecting the effects of residence time and/or variations in the oxygen isotopic composition of rainfall. Carbon isotopes have wide variations in both fluviatile and lake data sets (+ 3 to −12‰ PDB). These variations are principally controlled in the fluviatile samples by contribution of isotopically light ‘soil zone’ carbon relative to isotopically heavier carbon from limestone aquifer rock dissolution. Lake samples have the heaviest carbon isotope values, reflecting a trend toward isotopic equilibrium between atmospheric CO2 and aqueous HCO−3.We infer that isotopic compositions of ancient cyanobacterial carbonates should also record environmental information, although the effects of stabilization and diagenesis on primary δ18O values will need careful consideration. Primary carbon isotope compositions should be well preserved, although in marine samples values will be buffered by the isotopic composition of aqueous marine bicarbonate.

Seismic velocities beneath central and southern Britain from broad-band surface waves

Abstract Fundamental mode Rayleigh waves recorded across the UK broad-band network have been analysed to produce phase velocity curves in the period range of 12 to 85 s. An inter-station method has been used for two paths across southern England. The resulting mean phase velocity curve has been compared with a mean curve derived using three stations in central Britain. Lateral refraction characteristics of tripartite phase velocities have been analysed and shown to be less than 5° at periods of greater than 15 s. Forward modelling to S-wave velocity/depth profiles using a Hedgehog search procedure suggests that central Britain is underlain by a thicker crust than southern England, with a steady velocity increase down to the Moho. For southern England, low velocities are apparent either at the base of the crust or in the uppermost mantle. For both regions, sub-crustal lithosphere velocity is contrained to be between 4.6 and 4.7 km s −1 with a layer thickness of less than 140 km for southern England and between 80 and 160 km for central Britain. Both regions appear to exhibit low velocity zone (LVZ) development. However, for central Britain, more data are required to place better constraints on the magnitude of the LVZ channel. Velocities in the lower crust have been used to place constraints on Poisson's ratio which appears to decrease northwards from greater than 0.27, beneath southern England, to between 0.25 and 0.27 beneath central Britain. The distributions of P-wave velocities, S-wave velocities and Poisson's ratio have been interpreted of compositional variation and/or fluid content within the lower crust.

Structural trends in central Britain from images of gravity and aeromagnetic fields

Digital image processing techniques have been used to analyse the regional gravity and aeromagnetic datasets in central Britain. Colour and shaded-relief images have been generated which convey information on both anomaly amplitude (as colour) and anomaly gradient (as relief) and highlight structural trends, lineaments and textural contrasts not easily discernible on standard contour maps. We have identified some of the more important features and have tried to relate these to the evolution of the crust in each region. On a broad scale the images emphasize Caledonoid (ENE) trends to the north of the Solway line and both Tornquist (SE) and Caledonoid (NE to ENE) trends to the south. The pattern of magnetic anomalies over central England seems to define the extent of the shallow late Precambrian–early Palaeozoic basement of the Midlands Microcraton and delineates crustal elements and characteristic trends within it. Magnetic lineaments and the grain of gravity anomalies, trending in northeasterly and northwesterly directions on either side of the microcraton, seem to relate to structures which originated during the evolution of the Welsh and eastern English Caledonides respectively. Where Lower Palaeozoic and Precambrian rocks form the concealed ‘basement’, as in most of England, the gravity lineaments tend to reflect the influence of basement fractures on the subsequent pattern of sedimentation whereas many of the features on the magnetic images are more directly related to structures within the basement itself.

The effect of weather on the life cycle of the speckled wood butterfly Pararge aegeria

ABSTRACT. Pararge aegeria (L.) is a very unusual butterfly of Britain, having a long period of adult activity, from April to October, without discrete flight periods. In central Britain it overwinters in two stages: pupae and third instar larvae, both being the progeny of late summer adults. Other larval stages die at the onset of cold winter weather. The overwintering stages give rise to the first adult generation in spring, split into two parts. Different temperature regimes affect development rates in larvae and pupae differently. Late larval development is more rapid than that of pupae at low temperatures, thus in cool spring weather the overlap of the two parts of the first generation is greater than in warm spring weather. Adults emerge continuously throughout the summer because larval development rates are variable. When summer is warm there is a partial third generation but when cool only two. The timing of the end of the flight period is consistent with the hypothesis that both temperature and photoperiod are important in determining whether individuals enter diapause or develop directly. In warm summers larvae develop beyond a sensitive stage before critical daylength is reached and develop directly, but in cool summers individuals enter diapause because they are at the sensitive stage when critical daylength is reached. It is suggested that variable development rates can facilitate parasite escape in autumn and increase the probability of adult success when weather is unpredictable, and this strategy is maintained because these benefits are greater than the cost of winter mortality of larvae.

Frustrated Great Gamesmanship: Sir Garnet Wolseley's Plans for War against Russia, 1873–1880

Sir Garnet Wolseley, Viscount Wolseley of Tel el-Kebir and the very model of the modern major-general, is remembered for his reform of the army and for his successes in Ashanti and Egypt. Less is known of his views on how to fight a war against Russia and how to defend India from a Russian attack. His ideas on these subjects were first explained in any detail between 1873 an(^ 1880, as the result of the Great Eastern Crisis. This was the most serious and protracted crisis the British had to manage between the Crimean War and the First World War. It compelled them, in a way in which the Penjdeh Crisis, for example, did not, to work out their worldwide military and naval potential in a war against a major European military power. From 1873 onwards, Russia gained undisputed control over the routes to India across Central Asia and Britain gained equally undisputed control over the sea routes by way of the Mediterranean corridor. As a result, the Eastern Question, which had formerly to take account of the diplomacy, trade, and religions of Eastern Europe and Central Asia, was increasingly simplified by the British. It turned into a prolonged discussion of the best strategy for defending India and merged into the Great Game in Asia.

The distribution of bravoite and nickeliferous Marcasite in central Britain

The distribution of bravoite and nickeliferous Marcasite in central Britain

Fossil coleopteran assemblages as sensitive indicators of climatic changes during the Devensian (Last) cold stage

Goleoptera are abundant fossils in Quaternary deposits laid down under freshwater or terrestrial conditions. They display a remarkable degree of evolutionary stability and reasons are adduced for believing that this morphological constancy is associated with physiological constancy. Thus whole communities of species have been assembled in the past, drawn together by common ecological preferences, so that the species composition of fossil assemblages resembles that of modern faunas. Marked changes in the geographical distribution of Coleoptera during the last glacial-interglacial cycle conform to an orderly pattern of climatic fluctuations. The Coleoptera contribute most information about the Devensian climates during warmer interstadial periods because during the colder episodes conditions in Britain became more or less intolerable to insect life and the fossil content of the sediments approaches zero. The term interstadial is here used for an interlude of milder climate in an otherwise cold period which either does not attain temperatures equivalent to those of the present day or which attains temperatures as warm, or even warmer than those of today but which does not last long enough for floral and faunal equilibrium to become established. During the Ghelford Interstadial, at the limit of acceptable radiocarbon dating but possibly about 60000 years (a) ago, the climate in central Britain was rather cooler than now with a moderate degree of continentality. The Upton Warren Interstadial complex, between about 45000 and 25000 a ago, reached its thermal maximum at about 43000 a before present when temperatures were rather higher than those of the present day and the climate was moderately oceanic. This episode may have been as short in duration as 1000 a. After this the interstadial is characterized by a period of much lower temperatures, with a greatly increased degree of climatic continentality, lasting for about 15 000 a. Few insect faunas are known from the period of maximum ice expansion but the scant evidence supports an interpretation of a climate of arctic severity. During the closing phases of the Devensian cold period there is faunal evidence for only one major climatic oscillation - here called the Windermere Interstadial. The sharp rise in the thermal environment at its beginning took place rather before 13000 a ago but later than 14000 a ago. Thermal maximum was attained almost immediately with temperatures during the summer at or above their present day level. Moderate oceanicity of the climate at this time means that winter temperatures were not much lower than those of the present day. At least during the earliest parts of this interstadial a temperate insect fauna was associated with a flora almost entirely dominated by herbs. The decline of the Windermere Interstadial from its thermal maximum seems to have been more or less synchronous from southern to northern England and to have taken place at about 12 200 a ago. A cool temperate phase then ensued for over one thousand years with summers about 3 °G cooler than during the thermal maximum. This episode corresponds in time to the Allerod oscillation. The Loch Lomond Stadial between 11000 and 10000 a ago saw the return of arctic faunas to the British Isles even as far south as Cornwall. The presence of Asiatic species, though not abundant, suggests that the climate at this time may have been rather continental. The timing and intensity of the climatic changes during deglaciation show close parallelism to the changes in oceanic circulation in the eastern Atlantic now being interpreted from cores of ocean bottom sediments.

Birds of the Plesyumi Area, Central New Britain

previously investigated ornithologically. The Plesyumi area lies approximately 56 km SSE of Kimbe, in the eastern foothills of the Whiteman Mountains (fig. 1). It consists of the valley of the upper Metelin River and its tributary, the Lae River, which form part of the extensive Kapiura River system draining to the north coast. The entire area is covered with primary rain forest, except for small clearings at prospector camps established as a joint operation of the Amdex Mining Co. and Placer Prospecting (Australia) Pty. Ltd. The nearest native settlement is Paspas (Metelin) Village, located 24 km to the north.

Breeding Distribution of the Twite in Central Britain. Part 3 - Range and Distribution of the Twite

The Twite is the only avian Tibetan faunal element found in Europe and its present habitat in the oceanic climate zone of the British Isles and Scandinavia is very different from the ancestral montane environment. The author discusses how such a radical change in its ecology, and the present concentration in the Southern Pennines, might have arisen.

Breeding Distribution of the Twite in Central Britain

The range of the Twite in central Britain has contracted during the present century. Its headquarters today are the Southern Pennines, where it feeds in the upland pastures and nests in a variety of moorland habitats. This investigation reports on its present status and distribution, and describes in detail the bird's roosting, feeding and nesting habits, covering in general its ecological adaptation to this bleak and often inhospitable environment.

Structural profiles in the New Britain / New Ireland region

Abstract Seismic interpretations along lines of shots and stations in the New Britain/New Ireland region have revealed structural detail in this tectonically complex region. When correlated with marine and land gravity measurements, they indicate a comparatively uniform crust 18 km thick in the eastern Bismarck Sea, thickening to between 30 and 40 km approximately under New Britain and New Ireland. The interpretations indicate crustal thinning of the order of 8 km under the gravity high of central New Britain, and it is suggested that this is upwarping due to northsouth compressional forces. The gravity data indicate that a similar structure could apply to other islands in the Solomon chain. Shear forces seem to dominate the geological structure in the region of the Gazelle Peninsula and southern New Ireland, and the 30 km thick crust there contrasts sharply with an 18 km Bismarck Sea crust along the west coast of the Peninsula. The crustal thickness under New Ireland is the same as that under the islands...

Petrochemistry of volcanic rocks of the Harbour Main Group, Avalon Peninsula, Newfoundland

The predominantly volcanic Harbour Main Group of Proterozoic (Hadrynian) age forms a northerly-trending belt in the central part of the Avalon Peninsula, Newfoundland. The rocks include flows, pyroclastics, and several belts of well-preserved ignimbrites.Twenty-two recent chemical analyses of volcanic rocks, sixteen of them not previously published, show that the Harbour Main volcanic suite is distinctly sodic and weakly alkalic, ranging from basic rocks of the hawaiite–mugearite type to sodic rhyolites with relatively high alkali content; the alkali-lime index of the suite is 52.The Harbour Main rocks are shown to be chemically similar to the Late Precambrian Uriconian volcanic suite in Central Britain, with which it has been previously tentatively correlated on other grounds. It is suggested that the volcanic rocks of the Avalon Peninsula and the British Midlands were formed in different parts of a possibly continuous tectonic belt in a period of post-orogenic block-faulting of the Basin and Range type, prior to the opening of the present Atlantic Ocean.