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The Maltese Islands are situated at the south-western end of the Malta-Ragusa Rise, an area characterised by high gravity anomaly values and a ridge-like bathymetrical profile. The Islands lie 50-80km. south of Sicily and 282km. away from the north African coastline. The sedimentary sequence is entirely composed of shallow water carbonates, dominantly marine, and with biohermal developments in the upper and lower exposed formations. The intermediate formations accumulated in somewhat deeper water and are characterised by planktonic foraminifera. Subdivision of the Upper and Lower Coralline Limestone Formations into 7 new members and 11 new beds was found necessary, in order to appreciate fully the local environments represented in these shallow water units. The Globigerina Limestone and Blue Clay Formations are now considered as fairly shallow water deposits, the analysis of the associated phosphorite conglomerate beds of the former indicating that dominant transport of clasts was from the west, in an area of primary phosphorite and glauconite development. The Greensand Formation is re-defined on the basis of sedimentology, and the upper part of previous classifications is now included in the Upper Coralline Limestone Formation. For each of the Formations a total of 15 biofacies are proposed on the basis of faunal variation. The probable depth ranges of each are used to refine conclusions drain from the sedimentological interpretations, in order that the palaeoenviromnents may be reconstructed. The study of a newly defined brachiopod marker horizon within the Upper Corailine Limestone has resulted in the prediction of the ecology of the four species involved, primarily with the aid of bryozoan growth-form studies. A new fossil fish horizon in western Malta is also discussed. A number of tectonic structures previously referred to as "sinks" are re-defined, and a prolonged episode of Cainozoic cavern development, associated with subaerial and submarine subsidence is postulated on the basis of structural and sedimentological interpretations.

Earth surface movements are a primary external control on river system dynamics and evolution. It has often been observed that when responding to Earth surface motion driven by surface expression of folds, major rivers incise across young, active folds near their structural culminations and divert around others. This study shows that for the major rivers Karun and Dez in the Mesopotamian-Persian Gulf foreland basin, these different river responses are due to the need for narrow channel-belts to be maintained where a river incises across a fold, and the time it takes (at least several decades) for such narrow channel-belts to develop. In general, where a major river initially encounters a fold as an emerging fold “core”, the river flows across the uplifting fold for sufficient time for the development of a narrow channel-belt, thus producing an incising river course across the fold (a single “water gap”) in the vicinity of the fold “core” and the subsequent structural culmination. However, where a major river initially encounters a fold as a larger, emerged fold, the river does not flow across the uplifting fold for sufficient time, due to channel migration in response to lateral fold growth, thus producing a river course diverting around the fold “nose”. Hence, river reaches across the fold axis for river incision are characterised by narrow channel-belts, low channel sinuosities, high specific stream powers, and river crossing locations relatively near to the fold “core” (generally nearer than 16 km). By contrast, river reaches across the fold axis projection for river diversion are characterised by average channel-belt widths and channel sinuosities with fairly wide ranging values, fairly low specific stream powers, and river crossing locations relatively far from the fold “core” (further than 22 km). A narrow average channel-belt width of less than c. 2.7 km is a threshold for the rivers Karun and Dez (mean annual discharges c. 575 m³s¯¹ and 230 m³s¯¹) encountering folds in lowland south-west Iran (rates of uplift c. 0.1 - 2.3 mm yr¯¹), and this probably has a precedence over other geomorphological changes for producing river incision across a fold in response to uplift. In general, slightly smaller rivers are more frequently diverted around the fold “nose”, and small rivers and creeks, which are more easily “defeated” by fold growth, frequently develop a series of narrow “wind gaps” across a fold. The influences of human impacts on major rivers can be distinguished from those of Earth surface movements by suites of river characteristics. There may be significant interactions where these two external factors coincide, most notably where fold uplift and major anthropogenic river channel straightening produce the persistence of long, near-straight river courses (channel sinuosity < 1.1 over a river course > 10 km long).

This thesis investigates concepts of marginality and the response of human populations to changing environmental conditions in prehistoric Orkney. Archaeological remains from the Orcadian Bronze Age are less visible than those from the Neolithic and Iron Age, leading to suggestions that the Neolithic-Bronze Age transition represents a cultural and/or economic 'decline'. This 'decline' has often been attributed to environmental deterioration, although there is little published evidence for post-Neolithic environmental conditions in the islands and that which does exist comes from areas that are considered agriculturally marginal today. Palaeoecological records from three small wetland basins situated within landscapes with differing degrees of marginality are presented here. Radiocarbon chronologies for these sequences show that events previously assumed to be synchronous across Orkney, such as woodland decline, are in fact highly variable. High-resolution analysis has been carried out between c. 3000 cal. BC and c. 600 cal. AD (late Neolithic to Iron Age), and records compared with the distribution of archaeological sites in order to reconstruct changes in land-use, farming practices and settlement patterns across this time period. The new records have been synthesised with existing palaeoecological and archaeological data in order to review the evidence for the hypothesised 'Bronze Age decline' in Orkney. These data indicate that during the Bronze Age a pastoral specialism developed in the more marginal parts of Orkney while elsewhere arable cultivation intensified. This seems to have occurred in response to the fragmentation of society and population which is argued to have begun during the late Neolithic. There are indications of a slight climatic deterioration and of the spread of heathland at some sites in the late Bronze Age, and it seems that farming practices were adapted in order to cope with changing environmental conditions. Although there are distinct cultural differences between the Neolithic and Bronze Age, there is now no reason to suggest that Orkney underwent a 'decline' shaped by environmental deterioration during the latter period. The changes seen in the archaeological record at this time are likely to result from a combination of environmental, social and cultural factors.

This study is an integrated biostratigraphical and palaeoenvironmental analysis of foraminiferal and radiolarian distribution from all the major Middle and Upper Jurassic marine deposits of Scotland. These sampled sites are divided between two basins with Staffin Bay and Bearreraig Bay within the Inner Hebrides Basin, North West Scotland; and Brora, Balintore, Helmsdale and Eathie Haven representing the Inner Moray Firth Basin, North East Scotland.A detailed taxonomic section is presented, which provides the means of comparison of microfaunal events between sites. A combined total of 212 species are described, of which 183 are foraminifera and 29 radiolaria; this includes a total of 23 species not previously recorded, comprising 16 foraminiferal and 7 radiolarian taxa.A Callovian to Lower Kimmeridgian biozonal scheme, the first detailed attempted for the onshore UK, is constructed primarily using the Staffin Bay succession as the type section. It is based upon an integration of distinct foraminiferal and radiolarian taxa and events. This microbiostratigraphy is implicitly tied to the Boreal type ammonite scheme and comprises a total of 9 biozones and 12 sub-biozones. The new biozones are then correlated and compared with the other Scottish sites as well as other world-wide schemes.A sequential palaeoenvironmental analysis is outlined, firstly by pinpointing microfaunal assemblages that are based upon a combination of the distribution of the major suborders, the species diversity and faunal abundances, as well as integrating the facies types and probable prevalent substrate conditions. These assemblages are then used to define palaeoenvironmental models for each recorded succession, and are related to prevailing substrate and sea water conditions and distance from the 'palaeoshoreline'. As the assemblages are shown to reflect particular conditions this allows a generalised basin development model to be assessed, related to sea-level changes (transgressions and regressions). All the sites are subsequently correlated palaeoenvironmentally.The relevance of facies dependant distribution is also examined, particularly for benthic foraminiferids. The main conclusion reached is that facies dependence restricts the occurrences of taxa. However, this is not a constant feature as some specific taxa show the ability to colonise several facies types. It is this factor that permits a biostratigraphy to be constructed. Overall, assemblages appear to be related directly to a particular facies, which permits palaeoenvironmental changes to be assessed.Finally the extensive Middle and Upper Jurassic literature is examined and a generalised world wide biogeography constructed. Four provinces are defined based on characteristic foraminiferal and radiolarian assemblages.