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Aspects Of Efficiency In A Small Engineering Company, Michael Miles Jan 1987

Aspects Of Efficiency In A Small Engineering Company, Michael Miles

School of Engineering, Computing and Mathematics Theses

This thesis sets out to identify and discuss five of the subjects that were found to have a significant bearing on the attempts of a small engineering company to improve efficiency. The subjects detailed are production control, layout, costing, decision making and cost reduction. The bulk of the observations were made during a two year period spent as a Teaching Company Associate with a company (T.J. Filters PLC.) first evaluating and then implementing the opportunities offered by factory relocation. A new manufacturing facility was designed and built with a reduction in floor space of 31%. In the first two years …

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Tidal Stream Energy, E. M. Evans Jan 1987

Tidal Stream Energy, E. M. Evans

School of Engineering, Computing and Mathematics Theses

An investigation into the feasibility of tidal stream energy extraction is presented. The first part of the work is concerned with the economics, technology and costing of free stream tide mills for the deployment off the Channel Islands of Jersey, Guernsey and Alderney. Future fossil fuel prices are represented by three uniform rates of increase corresponding to overall increases of 200%, 100% and 50% in a 25 year period. Fuel replacement arguments indicate potential levels of investment in tide mills, pe r rate d kW, of £2040, £1574 and £1340 for Jersey and Guernsey and £3269, £2521 and £2148 for …

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A Simple And Versatile Interface To Feed Analogue Data From The Output Of Analytical Instruments To A Bbc Microcomputer, L Ebdon, Jig Alonso, Sj Hill, A Hopkins Jan 1987

A Simple And Versatile Interface To Feed Analogue Data From The Output Of Analytical Instruments To A Bbc Microcomputer, L Ebdon, Jig Alonso, Sj Hill, A Hopkins

School of Geography, Earth and Environmental Sciences

An interface is described to convert analogue data from the recorder or other output of a typical analytical spectrometer, or other instrument, to an amplified form suitable for feeding to the ADC of a microcomputer (BBC B+). The interface is simple and easy to construct, avoids complicated software, and can be used for a variety of applications. Excellent linearity was observed in transformed data and the interface is particularly suited to handling transient signals. Examples of its use in atomic absorption spectrometry, solution spectrophotometry and high performance liquid chromatography are given.

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Spectrochemical Analysis Of Whole Powdered Coal, Huw Gareth Michael Parry Jan 1987

Spectrochemical Analysis Of Whole Powdered Coal, Huw Gareth Michael Parry

School of Geography, Earth and Environmental Sciences Theses

The analysis of coal without sample dissolution was investigated by introducing coal slurries, into a variety of atom cells including electrothermal atomisation atomic absorption spectroscopy (ETAAAS), inductively coupled plasmas and direct current plasmas for atomic emission spectroscopy (ICP-AES, DCP-AES) and inductively coupled mass spectroscopy (ICP-MS). All the analyses were calibrated using aqueous standards. Slurries were injected into an electrothermal atomiser. The effects of furnace programme, background correction and air ashing were investigated. As, Se, Cd and Sb were successfully determined in a variety of certified reference material coals. For As the coal was slurried in nickel nitrate, magnesium nitrate, nitric …

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Synthetic And Biodegradation Studies Of Some Sedimentary Isoprenoid Hydrocarbons, John Nicholas Robson Jan 1987

Synthetic And Biodegradation Studies Of Some Sedimentary Isoprenoid Hydrocarbons, John Nicholas Robson

School of Geography, Earth and Environmental Sciences Theses

Over the past twenty years there have been many published reports of a group of abundant C20, C25 and C30 highly branched acyclic alkanes and alkenes in surface sediments. Synthesis and spectral and chromatographic characterisation of 2,6,10-trimethyl-7-(3-methylbutyl) dodecane (C20), 2,6,10,14-tetramethyl-7-(3-methylpentyl) pentadecane (C25) and 2,6,10,14,18-pentamethyl-7-(3-methylpentyl) nonadecane (C30) in the present study showed that these were the parent skeleta of the unknown hydrocarbons. Only the C20 hydrocarbon has been synthesised previously. Intermediates in the synthetic routes were also fully characterised. The synthetic alkanes and alkenes were used to assign structures to hydrocarbons in several sediments from Europe and Africa and a comprehensive …

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Optimisation Of The Inductively-Coupled Plasma For The Analysis Of Solutions And Slurries, Philip Norman Jan 1987

Optimisation Of The Inductively-Coupled Plasma For The Analysis Of Solutions And Slurries, Philip Norman

School of Geography, Earth and Environmental Sciences Theses

The application of inductively-coupled plasma (ICP) spectrometry for the analysis of solutions and slurries is reviewed. The critical parameters which affect analytical performance are identified and methods for the optimisation of the ICP for such applications demonstrated. Particle size of the suspended sample is shown to be the most important factor in the analysis of slurry samples. It is demonstrated that only particles less than 8 um in diameter reach the plasma even when the maximal diameter injector tube (3 mm i.d.) is used. Accordingly various methods for the reduction of particle size have been investigated and milling shown to …

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Chemical And Physical Analysis Of Laminated Sediment Formed In Loe Pool, Cornwall, David Alan Pickering Jan 1987

Chemical And Physical Analysis Of Laminated Sediment Formed In Loe Pool, Cornwall, David Alan Pickering

School of Geography, Earth and Environmental Sciences Theses

Laminated and annually-laminated sediments are found in Loe Pool. The origins of such laminations are investigated and evidence for their conditions of formation are presented. In all sediment analysed the combustion residue was greater than 80%, and in the black and grey annually-laminated sediment the organic matter was less than 3%. This indicated that the sediment was dominated by a minerogenic input. The high lacustrine sediment concentrations of copper, zinc and other heavy metals together with evidence from analysis of magnetic variables which indicated high levels of haematite, confirmed that a major sediment source was effluent from mine waste. Analysis …

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The Late Cenomanian Anoxic Event; Implications For Foraminiferal Evolution, Paul Niell Leary Jan 1987

The Late Cenomanian Anoxic Event; Implications For Foraminiferal Evolution, Paul Niell Leary

School of Geography, Earth and Environmental Sciences Theses

This study investigates the effect of the late Cenomanian Oceanic Anoxic Event (OAE) on the planktonic and benthonic foraminifera. On the former, the OAE was the cause of major extinctions within the population, the return to pre-OAE oxygen levels permitting recolonization of the vacated niches. On the latter, the OAE caused extinctions but resulted in a low oxygen tolerant fauna which slowly evolved into the vacated niches on the post-OAE recovery of oxygen levels. The changes in the foraminiferal populations have been integrated with changes in other marine organisms through the late Cenomanian.

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The Characteristics Of Synthetic And Natural Hydrous Iron Oxides In Aqueous Environments, Vincent Man Jan 1987

The Characteristics Of Synthetic And Natural Hydrous Iron Oxides In Aqueous Environments, Vincent Man

School of Geography, Earth and Environmental Sciences Theses

The work in this thesis is concerned with the Green Rusts, which are bluegreen metastable Fe(II) - Fe(III) hydroxy compounds incorporating anions such as SO42-, Cl- or CO3-. These Green Rust compounds (or Fe-GR compounds to distinguish them from the aluminium Green Rusts (Al-GRs) which are isostructural Fe(II) - Al(III) hydroxy compounds) can be produced in a consistent fashion from Fe(II) solutions by the method of induced hydrolysis using Fe(III) gel at pH 7 and under anoxic conditions. A series of sulphate and chloride Fe-GR samples were synthesised, and characterised primarily by the analytical techniques of M8ssbauer spectroscopy, X-Ray diffractometry, …

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The Emergence Of Delia Radicum In Relation To Agricultural Practice, Graham Brindle Jan 1987

The Emergence Of Delia Radicum In Relation To Agricultural Practice, Graham Brindle

Other Faculty of Science and Engineering Theses

Cabbage root fly passes through three generations a year in the south of England. The first generation peaks in late April to early May having overwintered in diapause. Recently, populations have been discovered in which the emergence of first generation flies was protracted, lasting until mid-July. The project aimed to investigate the incidence of late emergence in Devon and to examine the ways in which late emergers differed from early emergers in their progress through diapause. A new emergence trap was developed and used in conjunction with yellow water traps to monitor the emergence of cabbage root fly populations at …

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Radar Simulator Training For Effective Maritime Search And Rescue, Anthony Redfern Jan 1987

Radar Simulator Training For Effective Maritime Search And Rescue, Anthony Redfern

Other Faculty of Science and Engineering Theses

The main effort in locating and rescuing survivors of a maritime incident is borne by merchant shipping. This research shows that search and rescue is a task that will face most seafarers, but as they generally lack the necessary levels of skill and knowledge required the task will often be poorly performed. A remedy to this unsatisfactory situation lies in proper training and guidance for ships' officers. This thesis evaluates, using illuminative techniques, the first simulator course devised to provide such training. The evaluation will be of particular use to others called upon to provide similar training. It also shows …

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Linguistics In Vessel Traffic Services : An Investigation Of The Communication Problems In Inshore Waters, Frederick Fowler Weeks Jan 1987

Linguistics In Vessel Traffic Services : An Investigation Of The Communication Problems In Inshore Waters, Frederick Fowler Weeks

Other Faculty of Arts, Humanities and Business Theses

The ever-increasing sophistication of petroleum derivatives and dangerous and noxious chemicals carried by sea has resulted in a corresponding increase in the precautions taken by coastal states. High in importance amongst these precautions has been the introduction of Vessel Traffic Services, constituting shore-based organizations fulfilling a variety of functions, often based on advanced radar techniques. The kernel of any such system is communication, chiefly between shore and ship, ship and shore, but including communication ship to ship. Without such communications information cannot be passed, and advice and instructions cannot be given. This thesis describes the theoretical and practical linguistic research …

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Heavier Goods Vehicles - A Behavioural Approach To Costing And Rate Setting, Sharon Hallett Jan 1987

Heavier Goods Vehicles - A Behavioural Approach To Costing And Rate Setting, Sharon Hallett

Other Faculty of Arts, Humanities and Business Theses

The debates which foreshadowed the introduction of the 38-tonne vehicle in May 1963 focused on two main issues: the environmental effects and the financial effects. Whilst it is recognised that there are many problems with evaluating the former, it is usually assumed that the latter are well documented and, therefore, easily enumerated. This thesis illustrates that this is not so. Costs are calculated using deficient published tables of operating costs and are based on the assumption that operators make wholly rational decisions based on a full knowledge of their total costs. The use of these assumptions can result in misleading …

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Systems Approach To Documentary Maritime Fraud, Peter Kapoor Jan 1987

Systems Approach To Documentary Maritime Fraud, Peter Kapoor

Other Faculty of Science and Engineering Theses

Wring the last decade documentary maritime fraud has caused considerable financial loss. The internationality of the crime and the difficulties experienced in the investigation and prosecution of offenders has caused serious concern both nationally and internationally. The aim of this research was to examine the system of international trade in terms of flow between institutions, and to develop a model of the system to identify areas of system failures in terms of actual or potential frauds. A database consisting of 101 fraud cases was compiled. Detailed examination of the cases identified features common to different classes of fraud. Systems approach …

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Sailors' Wives And Husband Absence, Joan Chandler Jan 1987

Sailors' Wives And Husband Absence, Joan Chandler

Other Faculty of Arts, Humanities and Business Theses

This thesis reports on a study of women married to Royal Navy personnel and resident in the West of England and Wales. The analyses are based on data derived from secondary sources, a questionnaire survey and in-depth interviews, the field-work having been conducted between January 1985 and April 1986. Past research has concentrated on the emotional reaction of wives to husband absence, its relationship to anxiety and depression. This thesis is, however, concerned with the social situation of wives intermittently without husbands. It is an exploration of the marital and domestic consequences of husband absence and the implications it has …

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The Characteristics. Behaviour And Heterogeneous Chemical Reactivity Of Estuarine Suspended Particles, Anthony John Bale Jan 1987

The Characteristics. Behaviour And Heterogeneous Chemical Reactivity Of Estuarine Suspended Particles, Anthony John Bale

School of Biological and Marine Sciences Theses

A systematic, seasonal study of the distribution, behaviour and characteristics of the suspended and sedimentary particulate material in the macro-tidal Tamar Estuary and its influence on solution chemistry has been undertaken. This work has attempted to characterise the variability in particle properties associated with the major cyclic influences of the semi-diurnal and spring-neap and the seasonal climatic signals and to relate these findings to the distribution and transport of trace metals in estuaries. Characterisation of the particles involved measurements of surface charge using electrophoretic techniques, particle size, settling rates and densities, bulk compositional analysis and visual examination by scanning electron …

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The Dynamics Of Buried Seed Banks Beneath Woodlands, With Particular Reference To Hypericum Pulchrum, C.D. Darby Jan 1987

The Dynamics Of Buried Seed Banks Beneath Woodlands, With Particular Reference To Hypericum Pulchrum, C.D. Darby

School of Biological and Marine Sciences Theses

This study has examined the rate at which the seeds of certain species disappear from woodland soils, and whether the composition of the seed banks beneath stands of known age can be used to reveal management history. Associated with this is an investigation of the spatial distribution of the stored propagules. A question arises as to whether species with long lived seeds can survive as buried seed long enough to take advantage of the opening of the canopy and soil disturbance resulting from the falling of old trees. Given the great life span of most trees, this is a strategy …

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The Immune Response In Carp, Cyprinus Carpio L. To Ichthyophthirius Multifiliis, Fouquet 1876, Gillian Houghton Jan 1987

The Immune Response In Carp, Cyprinus Carpio L. To Ichthyophthirius Multifiliis, Fouquet 1876, Gillian Houghton

School of Biological and Marine Sciences Theses

Protective immunity of carp to ichthyophthiriasis has been confirmed, and demonstrated for the first time in juvenile carp, 10-12 weeks old. Standard immunisation procedures were developed here using the theront in preference to cysts. Immunisation included exposure of fish on 3 separate occasions of 14 day intervals to doses of approximately 2,000 theronts per fish, 80/ cm³. Procedures were controlled so that infections were not allowed to continue beyond the primary stage pH (7.0-7.2 ) and temperature (20±2° C) were maintained throughout experimental periods. Four weeks after third immunising dose, fish were exposed to a potentially lethal challenge, approximately 8,000 …

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The Impact Of Taxation On The Capital Budgeting Decision Of Corporate Groups, Lynn Hodgkinson Jan 1987

The Impact Of Taxation On The Capital Budgeting Decision Of Corporate Groups, Lynn Hodgkinson

Plymouth Business School Theses

The United Kingdom Tax system is not neutral with respect to a Company’s investment and financing decisions, that is incentives and disincentives to invest in particular projects or use particular types of financing arise through the imposition of taxation. Such biases may increase or decrease the value of capital projects, and if a company is to be certain of making accurate investment decisions the incremental tax flows arising due to the project must be included in the evaluation. The tax flows arising through the acceptance of a project may differ depending on the company's or group's tax profile, and therefore …

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Ocean Colour Analysis Using Czcs Data, David Hawkesford Lawrence Jan 1987

Ocean Colour Analysis Using Czcs Data, David Hawkesford Lawrence

School of Engineering, Computing and Mathematics Theses

A low-cost image processor has been designed and built to provide a system suitable for investigating the quantitative mapping of phytoplankton patchiness using Nimbus-7 CZCS satellite images. The processor design was based upon a Motorola 68000 computer linked to a 768x512x8 bit imagestore. High resolution images were input from the CZCS CCT via a 40 Mbyte tape transport. The system had the novel capability for real time linear and non-linear operations upon images on a pixel-by-pixel basis and fast evaluation (<10 seconds) of retrieval algorithms involving narrow band images. Software was developed to manage the images in the following ways: high emphasis filtering, edge detection, contrast stretch routines, rectification, and pseudo colour routines for grey-level colouring prior to display of the processed image on a double resolution colour monitor. Initial testing of the instrument was via multiband aerial photographs input through a broadcast quality camera, although the major analysis was carried out on CZCS data. Software was developed to correct the measured radiances at the satellite for atmospheric effects, thus giving values of the water-leaving radiances. In the correlation studies the sea truth was obtained in the form of chlorophyll concentrations determined during UOR surveys of the English Channel. Both high and low chlorophyll concentration scenes were analysed. The algorithm testing involved ratioing the radiances from the various narrow bands and incorporating them in quantitative expressions which were linear, logarithmic and polynomial. Four different images were investigated and the results showed that the observed chlorophyll concentrations were best correlated with water-leaving radiances through a linear expression. The spectral Information was also analysed with a clustering-technique to identify patches of chlorophyll of varying concentrations. The work shows that digital image processing can be used in conjunction with retrieval algorithms to provide real time detection of phytoplankton fronts in coastal waters .

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Genetic Variation For Fruit Development Of Pisum Sativum L., With Special Reference To The Effects Of The Rugosus Locus, Christine Mary Smith Jan 1986

Genetic Variation For Fruit Development Of Pisum Sativum L., With Special Reference To The Effects Of The Rugosus Locus, Christine Mary Smith

School of Biological and Marine Sciences Theses

This study has compared various aspects of pea fruit development, using two green-podded lines near-isogenic except for the r locus and a yellow-podded mutant having the genotype gpgp. The gp gene is associated with reduced chlorophyll in the pod wall which then appears yellow. The r gene is associated with a wrinkled appearance of mature dried seed and cotyledonary starch grains which are small and fissured. An ultrastructural survey of tissues from pods, testas and cotyledons showed there to be no effect of the r locus on chloroplast structure. The structure of amyloplasts however, appeared to be affected by the …

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A Three-Dimensional Numerical Model Of The Sea Breeze For The Plymouth Region, Ian W. Clark Jan 1986

A Three-Dimensional Numerical Model Of The Sea Breeze For The Plymouth Region, Ian W. Clark

School of Biological and Marine Sciences Theses

A three-dimensional, hydrostatic, primitive equation model is developed to simulate the Plymouth sea breeze. The equations are integrated forward in time on a staggered mesh with a domain of 64km X 64km X 3km, using a combination of central and upstream differencing. The ground surface is assumed to be smooth and the heat input to the atmosphere transferred vertically without the explicit use of diffusion coefficients. This results in a less stringent stability condition on the timestep, thus reducing the computational cost of the simulations. Sensitivity tests for a two-dimensional version are presented, examining the influence of atmospheric stability, the …

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A Seasonal Study Of Amino Acids In Marine And Estuarine Waters, Roger Evens Jan 1986

A Seasonal Study Of Amino Acids In Marine And Estuarine Waters, Roger Evens

School of Biological and Marine Sciences Theses

The fluram method for the analysis of amino acids was modified for use in sea and estuarine waters. No evidence for environmental coprecipitation of amino acids was found and any possible removal process from the Tamar estuary was most likely to be by some different mechanism. An HPLC method for the analysis of amino acids in natural waters suitable for shipboard use was developed. The method was used to determine the seasonal variation of amino nitrogen in coastal and estuarine waters in order to test the hypothesis that phytoplankton could use such compounds as a source of nutrient nitrogen when …

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Reproductlve Allocation In Flowering Plants, Ann Margaret Wilson Jan 1986

Reproductlve Allocation In Flowering Plants, Ann Margaret Wilson

School of Biological and Marine Sciences Theses

The proportion of resources which an organism devotes to reproduction has been assumed to be of great evolutionary and ecological significance. However, in previous studies of reproductive allocation (RA) in plants, there has been no consensus of precisely what is being measured nor how it should be measured. An attempt was made to determine the 'best' method of measuring RA and then apply this to a range of species with differing ecological strategies. Under nutrient stress caused by a low N treatment Taraxacum officinale and Poa annua were found to maintain their RA despite up to 4 fold reductions in …

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An Investigation Into Belief Biases In Reasoning, Julie Linda Barston Jan 1986

An Investigation Into Belief Biases In Reasoning, Julie Linda Barston

School of Psychology Theses

This programme of research investigates the effect of belief bias in syllogistic reasoning. Belief bias is conventionally characterised as a non-logical tendency to accept or reject deductive inferences on the basis of belief rather than logical argument. However, some theorists have argued that the effect is weak compared with that of logic and that it arises from misinterpretation of the premises or failure to accept the logical task. Despite the adoption of control s recommended in the recent literature. Experiments 1 to 3 found consistently strong belief bias effects on the syllogistic evaluation task. However, there were equally strong effects …

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Agricultural Analysis By Plasma Emission Spectroscopy With Slurry Atomisation, Simon Timothy Sparkes Jan 1986

Agricultural Analysis By Plasma Emission Spectroscopy With Slurry Atomisation, Simon Timothy Sparkes

School of Geography, Earth and Environmental Sciences Theses

The three electrode direct current plasma (DCP), has been investigated for the analysis of samples introduced using aqueous solution nebulisation, hydride generation and slurry atomisation. For aqueous solutions, simplex optimisation with signal to background ratio as the criterion of merit, vertical viewing position was found to be most critical. A continuous-flow hydride generator was interfaced to the DCP via a modified sample introduction chimney. Optimisation indicated that total sample introduction gas flow rates were essentially similar to those for conventional nebulisation and that vertical viewing position was again critical. Generation conditions for lead hydride were also simplex optimised. Acid, sodium …

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Flow Of Power Law Fluids With Application To Oil Drilling, E. J. Carter Jan 1986

Flow Of Power Law Fluids With Application To Oil Drilling, E. J. Carter

School of Geography, Earth and Environmental Sciences Theses

The thesis is concerned with a theoretical study of the flow behaviour of inelastic power law fluids in two different types of flow situation. These are: 1. The creeping motion of a sphere moving through an expanse of liquid. 2. The combined steady and oscillatory flow of a liquid through a straight tube of circular cross section. The first part of the work is devoted to the prediction of the drag correction factor for a sphere falling slowly through a bounded inelastic power law fluid. The analysis is carried out for the case when the outer spherical boundary has a …

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Studies On The Ground Flora Under Selection Forestry In The Tavistock Woodlands Estate, Marlene Jenssen Harris Jan 1986

Studies On The Ground Flora Under Selection Forestry In The Tavistock Woodlands Estate, Marlene Jenssen Harris

School of Geography, Earth and Environmental Sciences Theses

This thesis investigates the effect of the Bradford-Hutt system of selection forestry management, known as B-Plan, on the ground flora of the Tavistock Woodlands in Devon and Cornwall, England. After a review of continental selection forestry systems, the Bradford-Hutt system and its economic, production and ecological advantages are described. The study was conducted in four phases. Firstly, the canopy types were described. Then the ground flora was examined and related to canopy type, past history and management. Secondly, a vegetational community gradient was identified and examined in relation to the environmental gradients, canopy closure and soil moisture and to effects …

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Metal Methylation In Estuarine Waters, Andrew Paul Walton Jan 1986

Metal Methylation In Estuarine Waters, Andrew Paul Walton

School of Geography, Earth and Environmental Sciences Theses

Metal methylation has been studied in estiiarine waters by directly coupled GC-AAS/llquid nitrogen trapped hydride generation systems and determined accurately. Surveys were carried out in the estuaries of the River Tamar, Camon and Beaulieu (S. England) over a seasonal cycle. Methylated forms of Fb were only observed in rain, drain and estuarine water samples collected in the Tamar. In estuarine waters (GH«)«Fb*'' (<2-10 ng Fb 1"^) was the predominant methylated Fb species. Monomethylarsenic and dimethylarsenic species were observed in the water column in a ll3 estuaries studied. In the Tamar, Beaulieu and Carnon concentrations of methylated As species were similar with concentrations ranging from <0.02-0.7 pg As 1"^. In Tamar porewaters concentrations of methylated As species ranged from< 0.02-0.7 As 1"-^. Methylated forms of Se {Se(CH^)^, 0.5ug Se l"""-) were detected on an occasion in the Carnon. Modelling studies on Pb methylation suggest that conversion of trimethyllead acetate to Ti-IL proceeds by a chemical sulphide-mediated pathway (maximum 2.8% conversion occurred for a biological sediment system). Methylation of inorganic Pb ( H ) salts was not reproducible (maximum conversion of 0,OZQ% for PbGl^) but when observed a biologically mediated methylation process was invoked. From laboratory modelling studies temporal variations in As speciation observed in the Tamar were attributed to seasonal contributions of methylated As species from 3 sources: (i) macro-algae; ( ii ) diatoms; ( iii ) porewaters. The predominance of dimethylarsenic species over monomethylarsenic species in summer reflects the importance of plankton sources. In winter a transition takes place where the predominance of methylated As species occur and concentrations of monomethylarsenic species exceeds that of dimethylarsenic species. This transition is attributed to the increased importance of the porewater source in winter. The significance of metal methylation in the cycling of Pb, As and Se in estuarine waters appears to follow the order Asj>Se>^Fb. The biomethylation of As being highly significant in the transportation of As in the environment.

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The Sedimentology Of Fluvio-Aeolian Interactions, With Geological Examples From The British Isles, Chris Dodd Jan 1986

The Sedimentology Of Fluvio-Aeolian Interactions, With Geological Examples From The British Isles, Chris Dodd

School of Geography, Earth and Environmental Sciences Theses

In this study, both modern and ancient fan/fluvio-aeolian associations are reviewed. Criteria for recognition of ancient aeolian from fluvial deposits are defined. Four case studies were undertaken. Three are Middle to Upper Devonian sequences: a) The Caherbla Group, Dingle Peninsula, Eire, b) The Pointagare Group on the same peninsula, c) The Portishead Group, Avon. A Lower Permian sequence at Dawlish, Devon was also studied. The dune types in all four areas were barchan to transverse. Compound dunes (draa) occurred in the Caherbla and Portishead Groups. Some simple and compound dunes on the Caherbla dunefield margin were also reversing due to …

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