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Wicken Fen represents a remnant of the once extensive peat fenlands of East Anglia, which survived large-scale drainage efforts intended to bring land into agricultural production due to its importance within the local economy and subsequently as a site of interest to scientists. Wicken Fen is managed so as to conserve a variety of habitats lost as a result of drainage and therefore does not represent a truly natural environment. Traditional management practices on Sedge Fen, the largest part of Wicken Fen, involve maintaining a 3 – 4 year harvesting cycle and controlling soil water levels. Previous hydrological studies of Wicken Fen have determined that soil water levels are strongly influenced by precipitation and evapotranspiration. The evaporative flux at Sedge Fen is commonly estimated by using meteorological data within empirical formulae such as the Penman Monteith equation owing to measurement difficulties. Furthermore, there has been little investigation of the evaporative loss from fens within the UK. This study aims to investigate the evaporative loss from Sedge Fen so as to better inform hydrological management and to describe evapotranspiration estimation techniques which may be employed at other fen sites. Eddy covariance measurements demonstrated that evapotranspiration from Sedge Fen was typically less than reference evapotranspiration estimates. Evapotranspiration estimates may be improved by consideration of surface parameters which can be described using meteorological data. Meteorological differences existed between Sedge Fen and the surrounding area, resulting in differing evapotranspiration estimates depending on where data was collected. Evapotranspiration measurements were used within a simple water budget model of Sedge Fen and demonstrated the lateral movement of soil water, a hydrological flux previously assumed to be of little consequence within the hydrological balance of Sedge Fen.

Soil parent material exerts a fundamental control on many environmental processes. Nevertheless, resulting from the separate mapping programmes of the geological and soil surveys, parent material is currently poorly mapped in the United Kingdom. This research develops and tests four methods of predicting soil parent material using three study areas in England. The qualities of desirable parent material maps were stated, and then used to create new map value metrics to assess the success of the four methodologies. Firstly, translations of surface and bedrock geology maps to parent material maps were tested, using international and national parent material classifications. Secondly, qualitative expert knowledge of parent material, captured from published literature, was formalised into inputs for a corrected probability model. Parent material likelihood was predicted using three map evidence layers: geology, slope and soil. Thirdly, extensive data mining was used to create fully quantitative inputs for the same probability model, and the results were compared. The final method provided a quantitative framework for the expert knowledge model inputs by the incorporation of sparse data sampling. The expert knowledge method created parent material maps of higher value than those created by the translation of geological maps. However, the inputs derived from qualitative expert knowledge were demonstrated to benefit from the addition of quantitative sample data. The resulting maps achieved overall accuracies between 60% and 90% and contained numerous detailed classes with explicit probabilities of prediction. Extensive parent materials were shown to be predicted well, and physically and chemically distinctive parent materials could be effectively predicted irrespective of their extent. Parent material class confusion arose between units where the evidence datasets were unable to provide the sufficient geographic or descriptive detail necessary for differentiation. In such cases, class amalgamation was used to overcome consistent misclassification. Recommendations are provided for the application of this research.

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This thesis presents an integrated subsurface, field analogue and scaled physical modelling approach to the investigation of the autocyclic and allocyclic controls on braided river morphology and preserved alluvial architecture at both the channel-belt and within channel-belt scales. The prediction of inter-well alluvial architecture in the continental Barren Red Beds of the Upper Carboniferous, Lower Ketch Member, Southern North Sea, UK, presents difficulties. Subsurface data from the Tyne Field is subdivided into coarse-grained sandbodies (60%) alternating with siltstone lithofacies (40%). A depositional model is proposed representing an aggrading alluvial plain traversed by a series of 100 to 1100 m wide channel-belts with palaeochannel depths of between 1.5 and 3.5 m, and supplied with a fine grain size distribution (D50 = 0.08 mm). A seasonal climatic regime probably promoted crevasse splay deposition and development of extensive floodplains. The Tyne model can nest within a regional depositional setting where: (1) the predominant sediment supply was from the north; and (2) proximal to distal trends exhibit a grain size diminution, and a lowering of net-to-gross and connectivity. This thesis provides the first complete comparative study between the Tyne Field and an onshore analogue, the Eocene Escanilla Formation, Southern Pyrenees, Spain. New evidence is presented to suggest a fluvio-lacustrine setting for the Escanilla Formation. A marked qualitative and quantitative similarity between the two sedimentary sequences gives confidence in the analogue and permits the use of geometrical datasets, including sandbody width/thickness ratios, frequency distributions, channel-belt orientation and connectivity to be used in the construction of geological reservoir models of the Lower Ketch Member. Empirical estimates of channel-belt width in the prediction of sandbody geometry overestimate -75 % of the channel-belt sandbody widths measured from the outcrop, -because estimates fail to account for: (1) different channel patterns, (2) any autocyclic and allocyclic controlling mechanisms, and (3) vertical and lateral channelbelt stacking. Grain size is a key control on alluvial architecture at both the within channel-belt and channel-belt scale. Physical modelling of the Ashburton River, Canterbury Plains, New Zealand has allowed the impact of grain size to be isolated from other controlling parameters. Three reach-scale, generic Froude-scaled modelling experiments, incorporating a fourfold change in grain size have been undertaken in a flume facility that permits aggradation. Comparisons between model and field studies suggest grain size is not the most influential control on channel geometry. The modern Ashburton River exhibits no change in channel geometry downstream. However, a halving then quartering of the grain size distribution in the Ashburton River model resulted in: (1)channel geometries first deepening then widening, (2) the proportion of overbank sheet flow increasing, and (3) the duration of channel occupancy remaining constant. Under the boundary conditions imposed in the experimental study, grain size limits are recognised for scaled physical models, which suggest that physical models cannot reproduce Lower Ketch Member grain size distribution ranges. The preserved alluvial architecture from the Ashburton model is classified and quantified into six architectural elements. Architectural elements from the Ashburton River model show that alluvial architecture is dominated by channel fill deposits. An increase in primary channel fill width and thickness, an increase in splay widths, a higher proportion of preserved splay deposits, and a decrease in the size and frequency of occurrence of fine-grained architectural elements may all be attributed to a quartering of the grain size distribution. A methodology is presented to link permeability to the architectural elements of the Ashburton model, in order to supply data from the preserved stratigraphy of physical models to serve as inputs for the construction of both static and dynamic (fluid flow) reservoir models. In addition, the potential of an aggrading physical model to examine the impact of sampling frequency and up-scale averaging in the construction of reservoir models is explored.