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Submarine channel-levee systems are spectacular. geomorphological features extending down the continental slope and into the deep ocean basins. The evolution of channel-levee systems in relation to the flows which create them is particularly poorly understood, due to the inherent problems associated with direct monitoring. Additionally' previous lithofacies architecture models of submarine channel-levees, derived from seismic data, isolated core data and limited field studies currently have a limited resolution. Field observations of a submarine channel-levee complex within the Rosario Formation, Baja California, provide high resolution data of lithofacies and levee . depositional thickness decay along transects perpendicular to the channel axis. Within the levee, both sandstone thickness and the overall proportion of sandstone decrease away from the channel axis, in a channel-normal sense, according to a power-law.. Spatial variation in sedimentary structures away from the channel axis is also predictable and provides an important link to the depositional flow regime. The vertical succession within the levee indicates that the levee crest migrated outwards from the channel in response to increasing flow magnitudes and/or decreasing levee relief. Additionally, the spatial variation of ichnofacies within the levee is quantified and indicates a 'bioturbation front' which is indicative ofproximity to the channel. Intra-channel facies of the canyon confined portion of the· system include conglomerate scour fills and laterally amalgamated channel fills segregated vertically by overbank facies. Scours formed across previously 'quiet' areas, then coalesced into. what became the principal transport pathway. Scour fills can be traced laterally into thick sandstones which in tum pass laterally into a confined levee. Thin conglomerate bodies have a common facies association of matrix rich margins and a central wellsorted traction dominated deposit, these are interpreted as levees formed by frictionalfreezing at the margins of the flow. Axial parts of the channel fill are dominated by lateral accretion deposits indicating that these channels had a high degree of lateral mobility; this is also indicated by the rapid vertical alternation between thinly interbedded turbidites and thicker conglomerate packages. Laboratory modelling demonstrates that channel outer-bend sedimentation occurs from weakly confined flows, conversely more confined flows deposit at the inner bend; this may partly explain the spatio-temporal longevity of planform geometry commonly observed in submarine channels. The degree to which flows deposit overbank also relates to the degree of confinement, levee growth therefore reflects the degree of confinement. As levees increased in height their thickness along channel-normal profiles was increasingly well described by an exponential decay function. Additionally, sediment waves formed on the flanks of the levees, these commonly had intricate planform geometries which were found to relate to vortices which formed along channel margi~s due to the shear stress generated by faster moving and denser channelised flow. These vortices enlarge downstream and away from the channel as they decelerate across the overbank; in natural systems, vortex formation may explain the palaeocurrent swing which has been observed in both modem and ancient levee sandstones.

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This thesis considers and evaluates mathematical models and methods of data analysis used in the quantitative study of hillslope profile form. Models of hillslope profiles are brought together in a critical and comprehensive review. Modelling approaches are classified using five dichotomies (static/dynamic, deterministic/ stochastic, phenomenological/representational, analytical/ simulation, discrete/continuous). Profile data to serve as examples were collected using a pantometer in a 100 km(^2) square centred on Bilsdale in the North York Moors. Geomorphological interpretations put forward for this area include theses of profound lithological influence, polycyclic denudation history, proglacial lake overflow channels and profound cryonival influence. Profile dimensions, profile shapes, angle and curvature frequency distributions and bedrock geology can be related via a fourfold grouping of profiles. The use of quantile-based summary measures and of a method of spatial averaging and differencing are advocated and illustrated. Autocorrelation analysis of hillslope angle series appears to be of limited geomorphological interest, as autocorrelation functions tell a story of overall profile shape, which can be measured more directly in other ways. Problems of non stationarity and estimator choice deserve greater emphasis. Methods of profile analysis previously proposed by Ahnert, Ongley, Pitty and Young are all unsatisfactory. A method based on additive error partition and nonlinear smoothing is proposed as an interim alternative, and results related to bedrock geology. An approach to model fitting is outlined which treats specification, estimation and checking in sequence. A power function due to Kirkby is used as an example and fitted to field data for components. The exercise works well if regarded as a minimum descriptive approach but much greater difficulties arise if process interpretation is attempted.

A hydrological study was undertaken to investigate precipitation, evapotranspiration and runoff in the Browney basin, north-east England. The areal and seasonal distribution of precipitation during the period 1968-1972 were analysed and frequency analysis were carried out on the amount of rainfall and the number of raindays per month during the period 1939-1973 at Durham Observatory. There was a high correlation between yearly precipitation and altitude. October and September were the driest months of the year while February was the wettest month. The relatively high intensity rainfall in the late summer months gave evidence for the occurrence of convectional rain during this time of the year. A wide range in the amount of rainfall and in the number of rain-days for any given month at Durham Observatory was observed. To measure evapotranspiration two sets of evapotranspirometers were installed at two locations just outside the extreme eastern and western margins of the catchment. Other methods for measurement for estimation of evapotranspiration in the catchment were also used. These were the Penman and Thornthwaite formulae, the catchment water balance method and simple hydraulic lysimeters. The results of measured evapotranspiration at the two locations indicated greater evapotranspiration at the higher elevation. The use of simple hydraulic lysimeters for the measurement of actual evapotranspiration was discarded because of significant differences in the results of the replicates. A comparison of the catchment water balance evapotranspiration with the results from the other methods revealed that there was some moisture deficit in the catchment especially during the late summer months. Studies of runoff data from the catchment showed significant variations in the yearly, seasonal and short term patterns. These differences were explained by the differences in the amount and distribution of precipitation, evapotranspiration and antecedent soil moisture conditions. The overall hydrology of the catchment was studied by the simulation of the flow records during the period 1969-1973, using the Stanford Watershed Model IV. The results obtained revealed high correlations between the monthly recorded and simulated flows. The mean monthly recorded flow during the five year period exceeded the simulated flow by 2 percent. The actual evapotranspiration and groundwater components of the hydrologic cycle where also studies using the results of the simulation method.