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This project aims to test ideas, and propose new ideas where appropriate, about the topographic development ofsouthern Norway by studying the thermal and erosional history of the region. To this end apatite fission-track (AFT) analyses from 77 samples, as well as zircon fission-track and apatite (U-Th)/He analyses are reported. All apatite fission-track ages are mid Cretaceous to late Permian. It is demonstrated that southern Norway can be separated into crustal blocks with distinct AFT ages, bound by major Caledonian structures. Inverse modelling methods are used to extract cooling histories through the upper crust for all AFT data using individual and joint-modelling strategies. Cooling is interpreted in terms of denudation chronologies which are established for each crustal block. Rapid denudation (30-100 m Ma-l ) is inferred for the whole region in the late Permian and Triassic which is linked to a period of extension, faulting and relief development w~ich may have caused accelerated erosion. In most crustal blocks this is followed by a drop in denudation rate (to <10 m Ma-l ) in the Jurassic which lasts until the latest Cenozoic when rates are highest (although poorly constrained). Local deviations from these trends indicate periods of fault reactivation in the Mesozoic and Neogene. Theories that have been proposed as ex'planations ofthe present-day topography of southern Norway· . are assessed in light ofthe new data. Mantle based mechanisms oftopographic support are a poor explanation for observed AFT ages and the data is more compatible with long-term survival (since the end-Silurian) ofa Caledonian crustal root, buoyantly supporting the present-day topography. It is argued that this latter model is both simpler and consistent with all the available data and is therefore preferable. This interpretation has implications for understanding the topographic history of Palaeozoic orogens and high elevation passive margins worldwide.

'Science invites her admirers here, presenting one a knot of questions to solve respecting these rifted rocks, and those huge fragments of stone, that lie arranged in such orderly array ...' These words written of the Malham area in 1847 by A. McFarlane seem particularly appropriate to commence a work which attempts to look at a few of the questions regarding 'those rifted rocks'. The study of karst processes is yet in its youthful stages and it is hoped that the research presented in this thesis will advance to some degree knowledge of that part of England which 'presents us with creation in its boldest outlines' (McFarlane, 1847), in addition to furthering an understanding of the wider problems of the evolution of limestone terrains. In contrast to much speculative and theoretical reasoning that typifies some recent writings in limestone studies this work is based primarily, on systematic observations carried out on karst waters in the natural environment. There were six interrelated reasons for collecting this information: (i) To investigate in detail the role of antecedent hydro-meteorological factors, particularly effective precipitation and air temperatures,in initiating; (a) temporal variations in solutional losses at the sampling sites, (b) variations in the temperature of water recorded at these sites, and (c) the pattern of discharge fluctuations recorded at the selectedsites. (ii) In view of the recent separation of karst water into 'allogenic karst water' and 'karst spring water', or into percolation-fed springs and systems of the sink-resurgence type, it was considered important to discover how contrasts in the mode of recharge to the limestone could affect the recorded pattern of solute concentrations at the risings and the pattern of water-temperature variation recorded at the risings. (iii) Thirdly in view of the fact that recent work has pointed to the role of both lithological factors (Sweeting and Sweettng, 1969) and hydrological influences (Pitty, 1968,1971) in affecting mean solute concentrations in karst waters, regional variations in the mean solute concentrations and in the variability of solute concentrations are examined. (iv) Fourthly to discover those factors instrumental in causing regional variations in the mean temperature of water discharging at karst risings in the field area, and in causing regional variations in the level of fluctuation of water temperature at karst risings. (v) To investigate seasonal and regional differences in the time taken for circulating water to pass through the limestone systems (flowthrough times). (vi) Lastly to accumulate evidence concerning the nature of water disposition and ground-water flow in the limestones of the field area. This research was carried out in the Fountains Fell and High Mark upland areas of the central Pennines. These two areas provide a contrasting geological framework for this work, one area (Fountains Fell) being of limestone partially covered by Yoredale and Millstone Grit series, and the other (High Mark) consisting almost completely of Great Scar Limestone. Geological differences have given rise to the hydrological contrasts between the two areas with which some of this research is concerned. In addition this is an area of the Pennines in which comparatively little work has previously been carried out, earlier interests having been mainly centred on the Ingleborough area to the west, the locality of Malham and Malham Tarn, or in the southern Pennines. On account of the fundamental significance of geological, hydrological, biological and climatic factors to the operation of karst processes, a full description of these aspects of the field area is included in this work.

Existing flow measurement methods in natural gravel rivers are largely based on a series of point measurements detached from the dynamic nature of river flow. Traditional measurement methods are limited in many environments and locations due to an inability to access directly the channel; this situation is further complicated at high discharges where entry into the channel becomes impossible. The inadequacy of currently utilised flow measurement methods is highlighted in the study of riffle-pool sequences where limited data has produced gaps in the understanding of these fundamentally important bedform structures. Within the study of riffle-pool sequences the most prominent debates concern the precise means of sequence development and maintenance, the existence/operation of the velocity reversal hypothesis and the spatial compositions and periodicity of these quasi-regular bedform features. The expanding usage of remote sensor monitoring techniques, the incorporation of GPS receivers into drifters to provide improved positioning, and the adaptation of drifters for use in the surf zone and in estuaries and lakes have combined to highlight the potential of producing a GPS river flow tracer (GRiFTer). The development of a GRiFTer suitable for deployment in a natural gravel bed river system is described whilst the logistics of performing a field based GRiFTer investigation, data acquisition and analysis methods and the achievable accuracy of the approach are also considered. The development of a GPS River Flow Tracer provides an innovative approach to the acquisition of surface velocity measurements through the development of a series of GRiFTer based analysis tools and techniques. The suite of tools developed to date includes; the ability to measure a single primary flowline through a reach, a means of independently measuring the effective width of channel flow, the identification of low velocity zones (and the direction of flow within these areas), three different methods for the measurement of surface flow velocity (primary flowline, cross-sectional averaged and reach scale) and a means of defining riffles and pools from the relationship between depth and surface flow velocities. The study ultimately concludes with a conceptual model for the development and maintenance of riffle-pool sequences based on an adaptation of the flow convergence routing hypothesis.

This thesis reconstructs part of the deglacial and early post-glacial history of the River Tyne Valley, Northumberland. Data has been gathered through description and interpretation of sedimentary sequences and stratigraphies from quarry and cut-bank exposure, the development of a geochronology was attempted, based on optically stimulated luminescence (OSL), and broad-scale geomorphological mapping using traditional field mapping and appropriately scaled digital elevation models from NEXTMap Britain. The thesis contributes new detailed sedimentological and morphological data, and has re-evaluated existing data sets and interpretations. A number of sites have been investigated in very close detail, and the sedimentological analyses provide a much better understanding of their formational environment than morphological studies alone can do. The research in the Tyne Valley contributes to the growing body of work carried out by the extensive morphological mapping programs, with the detailed sedimentological and stratigraphic data vital for ground truthing remotely-sensed landform interpretations. The story of deglaciation in Britain is a complex one and the work here illustrates that we are far from understanding the behaviour of the ice during the last glacial period, and certainly there is not a one model fits all solution.

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