Sediments Of England Research Articles

The stratigraphy of the Cretaceous (Albian stage) Gault and Upper Greensand formations: Dorset to Buckinghamshire and the western Weald, UK

The present account is a review of the successions in the Albian Gault and Upper Greensand formations, their lithology and their ammonite biostratigraphy, proved at outcrop between Dorset and Buckinghamshire, in the western Weald and that recorded in boreholes in the intervening area. It is concluded that the Wessex and Weald regions formed a single sedimentary basin during the Albian Stage. The lithostratigraphy and biostratigraphy are described area by area and are combined with recent accounts of the Albian sediments of the adjacent regions to describe lateral and stratigraphical variations in the depositional environments and sources of sediment. We conclude that although the steady overall rise in sea level in the Albian had an important effect on the local depositional environments and in the distribution of Albian sediments in England and adjacent areas, the influence of intermittent tectonic phases on the development of transgressive erosion surfaces was such that individual pulses in global eustatic sea-level rise cannot be correlated with confidence with most of the transgressions in the Albian.

Development of a coastal dune sediment database for England and Wales: forensic applications

Abstract A database of coastal dune sediments in England and Wales has been developed with potential applications in forensic investigations. Coastal dunes are popular sites for criminal-related activities, including burial of drugs, weapons and murder victims. The coastal dunes and associated areas of windblown sand in England and Wales occupy an area of approximately 200 km 2 within 112 individual identified systems. Research has been undertaken to ascertain the spatial variation in sedimentological properties of the coastal dune sediments in England and Wales. Field sediment sampling has been undertaken at each dune system. More than 1500 sediment samples have been analysed by laser diffraction to determine particle size characteristics, and more than 500 have been analysed by inductively coupled plasma atomic emission spectrometry (ICP-AES) to determine chemical composition. Two examples illustrate how the database has been used in criminal investigation.

The hydroecological controls and conservation value of beetles on exposed riverine sediments in England and Wales

There are large numbers of records of uncommon beetles from exposed riverine sediments (ERS) (gravel, sand and silt shoals) in the UK. However, systematic surveys of their occurrence in relation to environmental controls are seldom undertaken. Data are presented here from a survey of 69 shingle ERS across England and Wales and used to establish which factors were important in constraining species assemblages. Over 480 species of Coleoptera were collected by a combination of pitfall trapping, hand searching and excavation techniques. A total of 81 species with conservation status of Vulnerable, Rare or Nationally Scarce were recorded during the work and this includes six species on the United Kingdom Biodiversity Action Plan (BAP) lists. A subset of 42 of these rare species can be classified as ERS specialists. The data were analysed using TWINSPAN, redundancy analysis (RDA), single factor ANOVA, general linear modelling (GLM) and correlation to examine the importance of selected environmental variables and their relationships with the species assemblages. The results indicate that: (i) ERS sites with large numbers of species that are either rare or exhibit strong fidelity to the sediments have a markedly western distribution in the UK and are found on unregulated rivers in Wales and a number of rivers in the south west of England, (ii) the type of substrate, habitat heterogeneity, the percentage of shade from trees, the percentage of fine sediments on the ERS, the amount of trampling and ERS size are important in determining invertebrate communities and (iii) ERS provide valuable and important habitats for rare beetles species in the UK. The importance of river regulation, engineering and trampling by stocking for ERS invertebrates is discussed.

The value of the organic cement matrix in the identification of the shells of fossil testate amoebae

Abstract. Shells of fossil testate amoebae isolated from lake sediments in England and Canada have organic cement matrices similar to those possessed by Recent specimens. The surface patterns of individual building units can be useful taxonomic features for confirming the identification of the many species of Difflugiidae found in these environments.

Studies of Carboniferous Fungi. II. The Structure and Organization of Mycocarpon, Sporocarpon, Dubiocarpon, and Coleocarpon (Ascomycotina)

The problematic organism, Sporocarpon, was among the first fossil fungi to be described. The genus was actually a heterogeneous assemblage of fungal forms, and was eventually divided into several taxa including Sporocarpon, Dubiocarpon, and Mycocarpon. In the present paper these organisms, as well as a similar, previously undescribed genus, Coleocarpon; are described from Lower, Middle, and Upper Pennsylvanian strata in North America, and from Upper Carboniferous sediments in England. Although initially considered to be radiolarian-like protozoa, these structures show far more similarity to ascomycetous cleistothecia. All forms are ornamented, spherical bodies with a complex wall which encloses scattered asci and ascospores. Taxa are distinguished primarily by differences in the organization of the cleistothecial wall. Structurally similar organisms are found today among the Eurotiales.

STUDIES OF CARBONIFEROUS FUNGI. II. THE STRUCTURE AND ORGANIZATION OF MYCOCARPON, SPOROCARPON, DUBIOCARPON, AND COLEOCARPON (ASCOMYCOTINA)

The problematic organism, Sporocarpon, was among the first fossil fungi to be described. The genus was actually a heterogeneous assemblage of fungal forms, and was eventually divided into several taxa including Sporocarpon, Dubiocarpon, and Mycocarpon. In the present paper these organisms, as well as a similar, previously undescribed genus, Coleocarpon; are described from Lower, Middle, and Upper Pennsylvanian strata in North America, and from Upper Carboniferous sediments in England. Although initially considered to be radiolarian‐like protozoa, these structures show far more similarity to ascomycetous cleistothecia. All forms are ornamented, spherical bodies with a complex wall which encloses scattered asci and ascospores. Taxa are distinguished primarily by differences in the organization of the cleistothecial wall. Structurally similar organisms are found today among the Eurotiales.

Revision of the stratigraphy of Permian and supposed Permian rocks of Southern Scotland

The formal stratigraphy of the Permian basins of southern Scotland is described for the first time. These rocks consist of piedmont breccias and lavas, overlain by wadi-fan and dune complexes, and alluvial fan and floodplain sediments. The sequences are inferred to be Stephanian to Lower Permian in age and correlatable with similar continental sediments in England and with the Lower Rotliegendes of Germany and the North Sea.

LXVI. The remanent magnetism of some sedimentary rocks in Britain

Abstract This paper describes a survey which was carried out to measure the natural remanent magnetism of Triassic sediments in England. Rocks from nine separate sites distributed over a wide area were found to have consistent polarizations, being magnetized in an approximately North East-South Westerly direction with dips significantly less than that of the present earth's field. Similar results were obtained for sediments of the Carboniferous and Old Red Sandstone periods taken from two other sites. Approximately half of the specimens showed reverse polarization. Tests were also made to measure the magnetic stability of the rocks. The possible implications of the results are discussed.

THE DEEPER STRUCTURE OF CENTRAL AND NORTHERN ENGLAND

( Read, January , 1949) Current views on the relations of the Anglo-Welsh and Scandinavian Caledonides are considered and it is regarded as unlikely that a connection exists between their southeastern fronts in Norway and the Welsh Borderland. From a consideration of surface-exposures and sub-surface records it is suggested that the Anglo-Welsh Caledonides form an arc—convex northwards—which surrounds the comparatively undisturbed area of the Midlands, in which the folding of the Lower Palaeozoic rocks is Variscide. This is supported by analysis of the foldings of the Upper Palaeozoic and later sediments of England, in which a strong posthumous Caledonide element is present. It is concluded that the eastward continuation of the Anglo-Welsh Caledonides lies in Central Europe, and not in Scandinavia. In his Presidential Address to Section C of the British Association in 1928, Bailey indicated the main tectonic elements in the structure of Europe in a lucid map (1928, fig. 1), which presents a fairly generally accepted view (e.g., Holmes, 1944, p. 385) of the general relationships and distribution of the Caledonide, Variscide, and Alpide mountain ranges (fig. 1). This map suggests two important problems :— ( a ) The Caledonide ranges are represented as striking northeastwards from the British Isles across the North Sea into Scandinavia. Their southwestern boundary traverses the Welsh Borderland, somewhere about the line of the Church Stretton Fault, and this is linked with the great southeastward overthrust of the southeastern border in Scandinavia, an overthrust claimed by Tornquist to be of order of 80 miles. ( b ) …