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The Strontian Granite in Argyllshire. is a composite pluton of late Caledonian age, emplaced into Moinian psammitic and pelitic rocks. It is composed of an outer tonalitic granodiorite (dated at 435 Ma.) passing into a porphyritic granodioritic, both xenolithic, and intruded by a younger alkali granite (ca. 400 Ma.).

In order to construct the most continuous balanced cross-section from undeformed foreland to higher thrust sheets in the southern Caledonides of Norway, selected areas of Cambro-Silurian rocks were mapped in the Oslo Graben. Undeformed rocks are only present in the southern part of the Oslo Graben and palinspastic reconstructions of the Oslo Graben restore the traditional thrust front in southern Mjosa 135km NNW of its current position. Therefore it is proposed that the thrust front now be recognised in the southern Oslo Graben. The traditional thrust front is interpreted here as the most southerly of a series of ramps in the Osen-Roa Thrust as it cuts. up section towards the SSE. After ramping through the Hedmark Group (Eocambrian) the Osen-Ro Thrust forms the bed-parallel detachment in the Alum Shales (Middle Cambrian) of the Oslo Graben. Therefore, it is proposed that the Osen-Roa Thrust Sheet continues into the Oslo Graben.

The field mapping of the Foyers Granitic Complex and its psammite envelope provided data to study the emplacement of the complex, and produce part of British Geological Survey Sheet 73E. The complex contains quartz diorite cut by quartz monzodiorite in the north, granodiorite in the south, and cross cutting adamellite stocks throughout the pluton. These units are the products of a differentiating magma body at depth. A north easterly trending suite of microdiorite dykes cross cuts the complex. The complex was emplaced into Grampian Group psammites, after the cessation of Caledonian orogenesis, and developed an extensive thermal aureole, with minor anatexis occuring in the inner aureole. Granitoid fabrics, enclaves, xenoliths and internal contacts imply emplacement whilst in a magmatic state. The adamellite was emplaced into a solid pluton. Boudinage and shearing in envelope psammites, and intense solid state fabrics in pre-Foyers granitoids, indicate the envelope shortened perpendicular to the complex margin. Major and minor D1, D2 and D3 regional structures are not rotated by granitoid emplacement. The orientations of the contact parallel psammite units are controlled by regional structures. Contact relationships between envelope and complex imply sloping was the major intrusion mechanism, with siliceous lithologies more readily sloped than others. Low density contrasts between granitoid and envelope necessitate sloping occured whilst the pluton was very fluid, extra bouyancy perhaps derived from connection with a magma source at depth. The Foyers Complex was emplaced as a series of stocks sloping into the crust. Regional structures controlled the morphology of the magma chamber because certain stratigraphic units either facilitated or hindered sloping. The positions of these units are controlled by regional structure. Ballooning of the magma chamber occured whilst the entire complex was fluid and deformed the envelope.

Clay-rich beds ('marl bands') in the Turonian of the Anglo-Paris Basin are primary features reflecting a sudden, sharp increases in non-carbonate deposition on the sea-floor. They differ from omission surfaces because they are not rhythmic, and usually only occur during eustatic falls in sea level. Subsequent to their deposition they have been modified by bioturbation and diagenesis. Marl bands containing a marl seem originated from a single, large influx of non-carbonate material. Flaser marls may have been formed from either a localised decrease in the amount of noncarbonate materiel deposited, or the deposition of several smaller pulses of non-carbonate material interspersed with white chalk sedimentation. Mineralogical investigation shows that they contain the same non-carbonate constituents as adjacent white chalks although the relative proportions of the two main clay minerals (smectite and illite) differ markedly in higher Turonian marls. The variation in clay mineral composition seems to reflect fluctuations in sea-level. Dinoflagellate cysts and the calcareous nannofauna do not appear to have been affected by marl band formation. In contrast, benthie foraminifera reflect the change in suface conditions with a marked decrease in the epifauna, and little change in the infauna. Stratigraphically, geochemical patterns reflect changes in the overall composition of the clay fraction, making it posslble to suggest in which of the two principal clay minerals each clay associated element occurs. Rare-earth element patterns show that the non-carbonate fraction of both white and marly chalk is of detrital origin. Oxygen stable isotope data implies that the formation of a marl is accompanied by a small (2-4°C) drop in ocean temperature. Analysis of a series of samples from widely spaced localities within the Basin shows that individual marls can be geochemically fingerprinted, and confirms the established lithostatigraphic correlations. Using this method, samples of prevlously uncorrelated marls from within and below the Chalk Rock and Spurious Chalk Rock can be allocated 'Basin' names. An attempt to correlate Northern Province marls with those in the Anglo-Paris Basin was unsuccessful. It is proposed that marls are formed as a result of erosion of clay-rich sediments from the borders of proximal emergent massifs at times of increased current activity induced by eustatic sea-level falls.

The distribution of dinoflagellate cysts in sediments of the mid Cretaceous from the western Anglo-Paris Basin are examined. Samples were collated from a range of facies types (i.e. basin margin-central basin), but particular emphasis was placed on those which represented deposition around the basin margins.

Western Colorado experiences a winter snowfall maximum and considerable snowmelt flooding in spring, followed by a summer characterised by short, high-intensity storms. An examination of local records and terrain characteristics suggests that not only are these two processes temporally distinct, but also that the environmental controls on runoff generation for each vary, so that each process affects different parts of the landscape. A gully system lying within a small (0.4 km squared) sub-catchment of the Alkali Creek basin was surveyed in 1962, 1975, and 1980. Because the watershed materials are erodible and sensitive to all watershed runoff events, it is hypothesised that the distinctive downstream erosion pattern described by the surveys may be explained in terms of the sediment transfer capabilities of the two asymmetrical hydrological process Intensity domains' routed into the channel phase. Frequency-weighted runoff models for melt and overland flow are consequently developed and tested against field discharge data. Linking these simulations to sediment rating curves allows event sediment yields for watershed sites to be estimated. The procedure shows snowmelt to be overwhelmingly effective in transporting sediment out of the basin, but that in the headwaters summer storm erosion is locally more important. A complex annual sequence of entrainment, lodging and flushing emerges which can be compared with other areas. Spatially differencing these yield data as an index of site scour and fill suggests that main channel erosion is considerable during snowmelt, and tributary junctions emerge as the most active watershed sites by a factor of at least 10. The peak power of simulated flows and the scour and fill indices work well in predicting contemporary form but less well against form change, nevertheless the methodology is generally supported by these results. Threshold behaviour is considered, and although it is argued that the sort of lodged sediments normally prone to trenching will not survive the snowmelt flushing on the main channel, there are possibilities for network Integration through fans on 'summer-sensitive' parts of the watershed. These possibilities and the large negative sediment yield budget indicate a state of chronic transience, an observation supported by evidence from an adjacent watershed.

A model of a changing tidal regime in an evolving shallow sea such as the ancient North Sea is developed and solved analytically as a generalization of Taylor's problem. Characteristic scales and coefficients are treated as functions of historical time. The z dependency, dissipative and non-linear terms are effectively separated from the governing equations by the use of a Latta expansion. A composite solution is found which takes account of each of these features. A Green's function technique is used to calculate the effects of friction. A sloping bed topography is simulated by a horizontally varying eddy viscosity.

Thin (1m), centrally inclined (cone) sheets of basic rock are a unique but common feature of the intrusive complexes within the Thulean Igneous Province. A field, structural, statistical and petrographic analysis of these sheets belonging to the Ardnamurchan Central Intrusive Complex has been made in order to determine their mode of emplacement.

The Glen Doll and Juan Jorge Complexes are two contrasting late Caledonian calc-alkaline plutons intruded into Middle Dalradian metasediments at the northern end of Glen Clova, in the Angus district of Tayside, Scotland. The Glen Doll Complex (12 km squared) constitutes a wide range of rock types from olivine gabbro, through diorite to adamellite. The bulk (> 80%) of the succession consists of heterogeneous hornblende- and pyroxene-bearing diorites. Partially assimilated rafted metasedimentary xenoliths, are common in the intermediate rock types. The basic rocks are cumulates which display wall-parallel layering. Mineralogical variation displays a transition from pyroxene-dominated anhydrous assemblages to amphibole-dominated assemblages. The diorites by contrast display floor-parallel layering and typically contain cumulate magnetite and ilmenite. Petrographic and mineralogical data suggests that fractionation played an important role in the evolution of the cumulate rocks.