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This thesis investigates the assertion by many early and more recent New Zealand glacial workers, that the high catchment rainfall and low seasonality in New Zealand create unique glacial sedimentary and geomorphic processes. Specifically the thesis examines the nature of glacial sedimentology and geomorphology in South Island, New Zealand focussing on the Rakaia Valley, as most of the early studies that suggested a distinct New Zealand process environment were based on South Island, East Coast glacial valleys. The thesis provides insights into glacial processes operating at glacial termini of late Quaternary glaciers in this region. The primary findings are as follows: Glacial terminus landforms (moraines) and sediments are described in two eastern (Rakaia and Ashburton Lakes) and one western (Waiho) valley of South Island. There are three main types of landforms 1) outwash head, 2) push moraines and 3) ice-contact fans. Outwash heads and push moraines have been identified before in New Zealand, but ice-contact fans have not. The spatial relationships between the three landforms can be complex especially where there is a fluctuating glacier terminus. Outwash heads are the dominant landform, with ice-contact fans deposited at a stationary terminus with channelised meltwater and push moraines preserved during retreat accompanied with outwash head incision. Both ice-contact fans and push moraines are prone to reworking into the outwash head. Supraglacial material comprises a small cap on the moraines and is usually insignificant in this system. The nature of past glacier termini can be gained from detailed study of these three landform relationships and their sediment record. The dominance of glacifluvial processes at the glacier terminus is a reflection of the low seasonality, abundant catchment rainfall, coupled with a large sediment supply. Preservation and deposition of the push moraines and ice-contact fans are controlled by glacifluvial processes on an outwash head, which in turn are controlled by the mass balance of the glacier. Sedimentology, stratigraphy and facies architecture were examined in the lower Rakaia Valley and elsewhere. The main environments recorded by these sediments are largely proglacial lacustrine and fluvial including 1) outwash gravels, with deposition of a sequence of glacier-fed, Gilbert-type deltas deposited over buried ice at Bayfield Cliff, 2) lacustrine silts and sands, 3) sub-aqueous ice-contact fans, 4) sub-aqueous mass flow deposits, and 5) supraglacial melt out material. These glacilacustrine facies are widespread during both retreats and advances. Sub-aqueous deltas are the primary ice terminus form, in this mid-valley lacustrine setting, which record termini advance and retreats. Syn- and postdepositional deformation of lacustine facies are also common as a result of pushing and overriding from the fluctuating glacier termini. Buried ice is also widespread and many of these deposits display evidence of disruption of sedimentation by its meltout. This implies that stagnant tongues of ice were often buried by outwash and lacustrine sediments. From the sediments and geomorphology described in this thesis, two main glacier terminus settings in New Zealand valleys are apparent A) when the glacier terminus is on or abutting its outwash fan-head, or B) when the glacier terminus is within its trough. Both the geomorphic and edimentological findings allow a better understanding of New Zealand glacial chronologies. Firstly, the sedimentology permits the identification of many more advances and retreats than are recorded in surface sediments. At Rakaia Valley, facies record six significant advances and retreats and many more small oscillations over the last 200 000 years. The geomorphic understanding and high resolution mapping has identified many more ice termini in the valleys than were previously recognised and allow the insights into ice margin behaviour through time. This includes the changing location of outwash heads and glacial troughs, with a migration up-valley since the OIS 6 advance/s, in the Rakaia Valley. The glacier overran its outwash head to reach its LGM position, and subsequently retreated slowly over about 10,000 years, back to its outwash head. It then changed to a calving margin and continued retreating but with no terminal moraines preserved, only lateral features. The research in this thesis has contributed to greater understanding of the New Zealand glacial system. Although low seasonality and large volumes of meltwater do play a role, and equally important control in New Zealand valleys is that of tectonics in terms of delivering huge sediment supply. This sediment supply enables large outwash head and fans to accumulate, which allow large stable lakes to form during glacier recession. The data and interpretations from this thesis will underpin the development of a New Zealand glacial land system, of which other valleys such as the Himalayas have. This land system development is important for understanding the temperate, high sediment yield glacial environment end member.

The structural framework of the northern Gulf of Mexico coastal zone is characterized by numerous growth fault systems. Neotectonic processes in coastal marshes in this region have been shown to be important drivers of relative sea-level rise as well as having significant influence on marsh accretion processes. One active growth fault has been identified at East Matagorda Peninsula, Texas. To characterize the Holocene behavior of this fault and the consequent sedimentary responses, a suite of fallout radionuclides (7Be, 137Cs, 210Pb) and radiocarbon, supplemented by sediment physical property data have been used to determine sediment mixing depths, rates of accumulation, and geochronology. Correlation of time-equivalent stratigraphic boundaries reveals a maximum total Holocene offset of ~1 meter. Determination of slip rates from these values reveals a linear trend of displacement as a function of distance along the fault trace with maximum slip occurring to the southwest and minimum slip to the northeast. Sediment accumulation rates from the downthrown station nearest to the fault trace display a dramatic increase over the last 30 years. Sediment bulk density and grain size data suggest an interaction between fault-driven geomorphic change and sedimentation where a migrating land-water interface has influenced the type of sediment accumulation here.

The Upper Triassic, Penarth Group has been examined, throughout Britain, both at outcrop and in boreholes. It is divided, lithostratigraphically into a lower, Westbury Formation and an upper, Lilstock Formation. Within these units a number of regionally-and locally-applicable members are distinguished. The Penarth Group is a predominantly marine, sedimentary sequence transitionally situated between arid or semi-arid lacustrine and fluviatile sediments (Mercia Mudstone Group and New Red Sandstone) and more fully marine strata (Lias). Early stages of the "Rhaetic" marine incursion, principally represented by the Westbury Member, document the establishment of semi-isolated, brackish basins which were superseded by a less restricted marine environment. This transgressional advance is linked to nutrient supply and thence to phytoplankton productivity in order to explain organic carbon profiles through the Westbury Member, Offshore and nearshore zones of this sea are recognised, the latter including sediments assigned to barrier-inlet, lagoon and tidal=flat environments. Clay mineral studies reveal an enrichment of smectite in offshore areas which is ascribed to differential sedimentation processes. Transgression was interrupted by a regressional phase marked by the lagoonal sediments of the Gotham Member. A shift in the zone of smectite deposition can be related to this regression. The inferred shelf-lagoon carbonates of the Langport Member reflect a renewal of transgression. A local influx of sediment-laden fresh- water is believed to have been responsible for the local change to the Watchet Member Facies. Deeper-water intermittently oxygen-deficient, marine environments are envisaged for the Pre-planorbis Beds. These spread across the Langport Member shelf-lagoon, as a result of continuing transgression, culminating in the widespread establishment of deeper-water conditions in the Lower Jurassic. An increase in kaolinite relative to smectite in these younger strata, reflects increasingly humid climatic conditions. A regional correlation of the lithostratigraphica.1 subdivisions is attempted leading to a series of palaeogeographical reconstructions.

Palaeoecological and sedimentological analysis has been applied in the study of Lower Carboniferous Waulsortian 'reefs' exposed in the Manifold Valley, North Staffordshire and in the Meuse Vallley in southern Belgium. Because Waulsortian 'reefs' have similar faunal, lithological and palaeogeographical characteristics in all of their occurrences it is argued that conclusions drawn from the Manifold and Meuse Valleys are applicable to the facies as a whole. Evidence is presented to show that lithological facies previously recognised within the Belgian Waulsortian can also be recognised elsewhere, and that changing sedimentation rates can explain many of their characteristic differences. Faunal and seimentological evidence indicates that the rate of sedimentation increased as the mounds developed. It is argued that the mound sediment was produced in situ and faunal data suggests that the surface of the mounds was firm. Early submarine lithification is thought to have been an important process in producing firm substrates and in maintaining steep depositional slopes. Fabrics and lithological components suggestive of early lithification have been recognised. A general model for Waulsortian development, based on conclusions drawn in this thesis, is presented.

This thesis investigates the application of complex adaptive systems approaches (e.g. Artificial Neural Networks and Evolutionary Computation) to the study of coastal hydrodynamic and morphodynamic behaviour. Traditionally, nearshore morphological coastal system studies have developed an understanding of those physical processes occurring on both short temporal, and small spatial scales with a large degree of success. The associated approaches and concepts used to study the coastal system at these scales have primarily been linear in nature. However, when these approaches to studying the coastal system are extended to investigating larger temporal and spatial scales, which are commensurate with the aims of coastal management, results have had less success. The lack of success in developing an understanding of large scale coastal behaviour is to a large extent attributable to the complex behaviour associated with the coastal system. This complexity arises as a result of both the stochastic and chaotic nature of the coastal system. This allows small scale system understanding to be acquired but prevents the larger scale behaviour to be predicted effectively. This thesis presents four hydro-morphodynamic case studies to demonstrate the utility of complex adaptive system approaches for studying coastal systems. The first two demonstrate the application of Artificial Neural Networks, whilst the latter two illustrate the application of Evolutionary Computation. Case Study #1 considers the nature of the discrepancy between the observed location of wave breaking patterns over submerged sandbars and the actual sandbar locations. Artificial Neural Networks were able to quantitatively correct the observed locations to produce reliable estimates of the actual sand bar locations. Case Study #2 considers the development of an approach for the discrimination of shoreline location in video images for the production of intertidal maps of the nearshore region. In this case the system modelled by the Artificial Neural Network is the nature of the discrimination model carried out by the eye in delineating a shoreline feature between regions of sand and water. The Artificial Neural Network approach was shown to robustly recognise a range of shoreline features at a variety of beaches and hydrodynamic settings. Case Study #3 was the only purely hydrodynamic study considered in the thesis. It investigated the use of Evolutionary Computation to provide means of developing a parametric description of directional wave spectra in both reflective and nonreflective conditions. It is shown to provide a unifying approach which produces results which surpassed those achieved by traditional analysis approaches even though this may not strictly have been considered as a fiddly complex system. Case Study #4 is the most ambitious application and addresses the need for data reduction as a precursor when trying to study large scale morphodynamic data sets. It utilises Evolutionary Computation approaches to extract the significant morphodynamic variability evidenced in both directly and remotely sampled nearshore morphologies. Significant data reduction is achieved whilst reWning up to 90% of the original variability in the data sets. These case studies clearly demonstrate the ability of complex adaptive systems to be successfully applied to coastal system studies. This success has been shown to equal and sometimess surpass the results that may be obtained by traditional approaches. The strong performance of Complex Adaptive System approaches is closely linked to the level of complexity or non-linearity of the system being studied. Based on a qualitative evaluation, Evolutionary Computation was shown to demonstrate an advantage over Artificial Neural Networks in terms of the level of new insights which may be obtained. However, utility also needs to consider general ease of applicability and ease of implementation of the study approach. In this sense, Artificial Neural Networks demonstrate more utility for the study of coastal systems. The qualitative assessment approach used to evaluate the case studies in this thesis, may be used as a guide for choosing the appropriateness of either Artificial Neural Networks or Evolutionary Computation for future coastal system studies.