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The response of salt marshes to sea level rise is dependent upon the availability of an adequate sediment supply and the subsequent rate of accretion of sediment on the salt marsh surface. On the north Sefton coast, the geomorphology and sedimentology of the area has resulted in the continued expansion of salt marsh within the outer reaches of the Ribble Estuary, enhanced by human activities over the last 200 years. The area has undergone significant human alteration in that time.

Cosmogenic nuclide concentrations in alluvial sediment are now routinely used to estimate time and space-averaged catchment-wide denudation rates, but have the potential to offer considerably more. This is because each grain leaving a catchment has a potentially unique history of erosion, transport and storage, and so the frequency distribution of cosmogenic nuclide concentrations in large numbers of grains can provide an integrated signature of the catchment's geomorphic history. This thesis evaluates the extent to which aspects of source area geomorphology and geomorphological processes can be inferred from frequency distributions of single grain detrital cosmogenic nuclide concentrations through the use of a combination of cosmogenic Be-10 and Ne-21 analyses and numerical modelling. The Gaub River study catchment is a tributary of the ~15,500 square km Kuiseb, one of the major ephemeral river systems draining western Namibia. The geomorphology of the upper Gaub is that of a high elevation passive margin and is characterised by an extensive low relief upland region and a highly dissected, high-relief zone marking the Great Escarpment. Denudation rates in the steeper escarpment sub-catchments of the upper Gaub, based on analysis of Be-10 concentrations in 6 amalgamated sediment samples, range from 12.5±0.8 to 14.1±0.9 m/Myr. These rates are twice those obtained for 5 upland plateau sub-catchments: 3.4±0.2 to 8.0±0.5 m/Myr. The Be-10 analyses show that there is a very strong linear relationship between measured denudation rate and mean slope of a sediment sample's source catchment. The analysis of Be-10 in a sample from the outlet of the Gaub and in the 11 sub-catchment samples confirms that, despite the strong geomorphic asymmetry that characterises this catchment, sediment leaving the upper Gaub is well mixed.

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In deep-water clastic successions biostratigraphy is routinely used to provide a framework for correlation through biozonation schemes and to infer general depositional setting.  There is, however, an absence of rigorous, quantitative, data to support palaeoenvironmental interpretations at the detailed scale of recognizing the different architectural elements of deep-water depositional systems, especially those that have similar sedimentological and wireline log signatures when seen in isolated vertical subsurface sections.  This study therefore investigates the foraminiferal micropalaeontology of the Kirkgecit Formation of the Elazig Basin of eastern Turkey in order to test the applicability of biostratigraphy to detailed palaeoenvironmental determination.  The project endeavours to test spatial variability in biofacies and evaluate this in terms of determining subsurface geometry.  An underlying theme of the investigation is to relate palaeontological to sedimentological data and to develop novel interpretations and prediction of the elements in the evolution of deep-water clastic systems. The study has focused on the quantitative foraminiferal assemblages (biofacies) of fine-grained sediment associated with the sedimentologically-defined sand-rich turbidite architectural elements.  It has been possible to interpret and define 15 architectural elements in terms of their inherent foraminiferal biofacies.  Additionally it has been possible to subdivide sedimentologically very similar architectural elements into new elements of finer resolution.  Broader biofacies variation has been linked to variations in palaeobathymetry. In terms of biofacies, attention has focused on the morphogroups represented by the formaminifera, rather than classical taxonomy.  This has avoided the uncertainties inherent in classical taxonomy such as variation with species concepts and synonymy.  Instead attention has focused on morphological variation associated with differing environmental parameters, especially water energy/motion substrate and oxygenation.  Eleven morphogroups have been defined, each further divisible into four subgroups based on ornament.

Interest has been stimulated by discovery of hydrocarbons in turbiditic sandstones interpreted as submarine slope deposits. The aim of this study is to test models of slope development, and to document the variety of gravity flow processes and products within deep-water lower-slope regions. This has involved a comprehensive sedimentological study of the geometry, facies distribution and spatial and temporal variation of internal architectural elements within deep-water clastic successions from three study areas. The Maras Foreland Basin (Miocene) contains an exhumed deep-water slope succession. Two laterally equivalent intervals highlight the complex lateral facies transitions that occur in lower-slope regions. The Macduff Slate Formation (Cambrian/Ordovician) was deposited in a deep-water passive margin environment and contains associated glacial deposits. Following deposition the sediments experienced several phases of regional metamorphism and associated deformation. A detailed structural and sedimentological study of several laterally equivalent intervals determined that the sediments were deposited in a sinuous, aggradational channel system with associated levee-overbank elements. Six age-equivalent cored reservoir intervals, offshore Côte d’Ivoire, West Africa (Cretaceous) were deposited on a submarine slope during late syn-rift extension. A comprehensive sedimentological study complimented by petrophysical and seismic data determined that deposition occurred within a series of stepped mini-basins or tilted fault blocks. There is evidence that the basins did not fill uniformly and that fault activity during sedimentation controlled sediment distribution patterns across faults, intervening transfer zones and within fault blocks. The three study areas differ in age, basin type, grain-size range and the interpreted length and geometry of the shelf-to-slope profile, but contain comparable facies associations linked to depositional architectural elements predicted by models of lower-slope successions.

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