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The Monmouth and Brightseat Formations contain a rich and diverse dinoflagellate assemblage. Thirty-five genera and sixty-six species, of which two genera and eight species are new, are described in this study. The stratigraphic distribution of the taxa is summarized in Figure 4. The content of the assemblage changes suddenly at the Cretaceous-Tertiary boundary with thirteen species making the~r first appearance at or just above the boundary. Nineteen species cross the boundary and thirty-five species are restricted to the Cretaceous. The rather sudden change in the nature of the dinoflagellate assemblage at the boundary is interpreted by the author to indicate a paraconformable relationship between the Cretaceous and Paleocene sediments. The term paraconformity is used since there is little field evidence (a few pebbles, some lignite, and evidence of boring) indicating any extensive period of erosion at the boundary. / Master of Science

The salient points of the thesis are summarised as follows. 1. The first chapter is essentially a review of chemical and mineralogical transformations accompanying the weathering of some primary rock forming minerals, and includes a discussion of feldspars, trioctahedral and dioctahedral mica, quartz, chalcedony, opal, metamorphic, accessory, and opaque minerals, and ferromagnesian minerals. Included therein is a hypothesis for the mechanism of formation and layered structure of hydrobiotite. 2. A brief review of the geology, geomorphology, <and age of weathering in north east Scotland is presented in chapter 2. 3. The geology, field work and laboratory investigations of the weathe~ing in a meta-sediment, a quartz-mica-schist, and the Tertiary gravels at two sites, are presented in chapters 4, 5, 6 and 7 respectively. Some features found are considered to be relic, and formed under previous conditions. The weathering products include 2:1 type and kaolin minerals. 4. Secondary silica in a minute form was found to be common and is referred to as "aphanitic silica". The main optical properties and occurrence have been noted. 5. Secondary deposits of Ti02 (leucoxene) are also common, and because of the great opacity of Ti02, may be very ;caospicuous in thin sections even though actual concentrations are very low. Some of the leucoxene is shown to contain rutile and anatase. The source of much Ti02 may be biotite, and very rarely Ti02 may apparently completely pseudomorph biotite. 6. A comparison of the kaolin minerals (poorly ordered kaolinite, well-crystallised kaolin'ijte,and halloysite) from some sites has been made by a variety of techniques including thin sections, X-ray diffraction, DTA, infrared spectroscopy, chemical intercalation, and electron microscopy. Some problems in the study of these clays are considered, particularly with respect to monomineralic and polymineralic mixtures. It is concluded that there are fundamental differences between the structures of kaolinne and halloysite, other than the occurrence of interlayer water in the natural state of halloysiteamphiboles and pyroxenes (generally), tremo1ite-actino1ite, and accessory minerals in the weathered materials is discussed and summarised. 8. The age of weathering and the contribution of weathering products to contempotary soils is assessed from a consideration of the evidence found and that available. It is concluded that in north east Scotland contemporary weathering has very little effect upon weathered rocks beneath soils

Sediments serve as the ultimate sink for many hydrophobic organic compounds and thus present a residual environmental risk many years after sources of contamination are eliminated. Monitored natural attenuation and ex situ treatment processes are often ineffective for treatment; as such in situ remediation technologies (i.e., capping) are under review. A conventional in situ remediation technology for refractory sediment contaminants is placement of a clean layer of material as a cap. A series of design models was developed to predict the performance of caps composed of the traditional material, sand. A passive sampling method using polydimethylsiloxane (PDMS) fibers for evaluating the performance of caps was developed and tested in the laboratory. The results of the laboratory analysis showed the ability to measure pore water concentration profiles in caps, the consistency of profiles with design model predictions, and correlation of PDMS-derived concentrations with contaminant uptake in test organisms. Potentially more effective caps composed of permeable adsorptive materials (to retard contaminant migration) and impermeable materials (to divert groundwater flow) were placed along with a conventional sand cap in the Anacostia River in Washington DC in 2004. Field tests of this site showed the ability to measure in situ pore water concentration profiles in caps using a field-deployable version of the PDMS passive sampling device and demonstrated the necessity of pore water-based approaches for analyzing caps. A model for assessing the uptake rates of HOCs within PDMS fibers was developed and shown to predict the kinetics of HOC sorption into fibers. The model is based on external-mass transport processes, which through a series of analyses were shown to be more significant than internal diffusion in PDMS fibers. Using the PDMS approach, field bioaccumulation tests at the Anacostia site as well as at San Diego Bay and Hunters Point Naval Shipyard showed stronger correlation of PDMS-based pore water concentrations than solid-phase concentrations with observations of bioaccumulation in the field. The overall conclusions suggest that pore water concentrations can often be a better indicator of risk than bulk solid concentrations. / text

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