Chromite in the mantle section of the Oman Ophiolite: Implications for the tectonic evolution of the Oman Ophiolite

Chromite in the Oman ophiolite is located in the mantle section of the ophiolite sequence and forms abundant small podiformdeposits throughout the length of the ophiolite (Rollinson, 2005).The Oman ophiolite has an exposed mantle section of ca 10 000 km2, and contains ca 200 chromitite bodies. Most are less than 10 000 tonnes and a only a few are >30 000 tonnes (Boudier and Al-Rajhi, 2014). We have examined these deposits in eight different areas of the ophiolite (Figure 1, Rollinson and Adetunji, 2013a), two of which we have studied in great detail – in WadiRajmi in the north of Oman (Rollinson, 2008) and atMaqsad in the south(Rollinson and Adetunji, 2013b).University of Derby URS

There were no large volumes of felsic continental crust in the early Earth

New model growth curves for the continental crust based upon Hf-isotopes in zircon suggest that large volumes of felsic continental crust were present in the Hadean and early Archaean. These models sit uncomfortably with estimates of the volume of ancient crust preserved today and imply that the large volumes of crust that were created early in Earth history are now lost. However, this paper argues that there is no evidence from modern mantle geochemistry that very large volumes of early continental crust have been recycled into the mantle. In contrast significant volumes of Archaean crust may have been reworked into younger crust, although there is no evidence that this process took place in the early Archaean and Hadean. Geological evidence from the detrital zircon record does not show evidence for large volumes of very early felsic crust, rather, geochemical proxies for Eo-Archaean and Hadean crust strongly suggest that the earliest crusts on Earth, some of which may have been subaerial, were mafic. A lack of very early felsic crust on Earth calls for a re-evaluation of current crustal growth curves and geodynamic models for the start of plate tectonics, the role of supercontinents in early continent formation and the role of the subcontinental lithosphere in continent preservation. The earliest felsic rocks on Earth may have taken the form of oceanic plagiogranites or ocean-island potassic granites as found in the modern.University of Derby URS

Archaean crustal evolution in West Africa: A new synthesis of the Archaean geology in Sierra Leone, Liberia, Guinea and Ivory Coast

A new synthesis of the geology and geochronology of the little-known Archaean rocks in Sierra Leone, Liberia, Guinea and Ivory Coast is presented in order to better understand the processes of Archaean crustal evolution in this region, and to attempt to interpret these data in the light of our current understanding of Archaean crustal evolution. In addition, this study seeks to identify those aspects of Archaean crustal evolution which are currently not known in this area and which need to become the subject of future studies, given the economic importance of this region in terms of the mineral deposits hosted in the Archaean rocks. These include greenstone-belt hosted iron ore, lode gold, chromite and columbite-tantalite and younger diamondiferous kimberlites intrusive into Archaean felsic gneisses. The new results show that this cratonic nucleus comprises of four main geological units: 1. The oldest crust is made up of 3.5-3.6 Ga TTG (tonalite-trondjemite-granodiorite) gneisses. These only outcrop in the east of the craton in Guinea but their presence is indicated elsewhere in the central part of the craton though xenocrystic zircon cores in younger rocks. 2. The major rock type found throughout the craton is 3.26-2.85 Ga TTG gneiss. In detail these magmas are thought to have formed in two episodes one between 3.05-3.26 Ga and the other between 2.85-2.96 Ga. The presence of inherited zircons in the younger suite indicate that this event represents the partial reworking of the older gneisses. 3.4 Ga eclogite xenoliths in kimberlite derived from the sub-continental lithospheric mantle are thought to be the restite after the partial melting of a basaltic protolith in the production of the TTG magmas. 3. Supracrustal rocks form linear belts infolded into the TTG gneisses and metamorphosed to amphibolite and granulite grade. They are of different sizes, contain a variety of lithological sequences and may be of several different ages. The larger supracrustal belts in Sierra Leone contain a thick basalt-komatiite sequence derived by the partial melting of two different mantle sources, unconformably overlain by a sedimentary formation. They are seen as an important resource for gold, iron-ore, chromite and columbite-tantalite. 4. A suite of late Archaean granitoids formed by the partial melting of the TTG gneisses in a craton wide deformation-metamorphic-partial melting event at 2800 +/- 20 Ma. This thermal event is thought to be responsible for the stabilisation of the craton. This new synthesis highlights major geological and geochronological similarities between the Archaean rocks of Sierra Leone, Liberia, Guinea and Ivory Coast and those in the Reguibat Shield in the northern part of the West African Craton suggesting that the two regions were once more closely related.UoD URS

Understanding the factors that influence the provision of 1:1 care in residential homes for older adults : an application of the theory of planned behaviour

Objectives To use the theory of planned behaviour to explore the factors affecting the decision of professional carers to provide 1:1 care in residential homes for older adults. Design A cross sectional survey design was used to assess 102 carers in 17 residential homes. A small sample returned a repeat assessment allowing a longitudinal examination of the relationship between intention and actual behaviour. Methods A questionnaire was written in accordance with the theory of planned behaviour guidelines and developed through interviews with carers. Standardised questionnaires were used to assess resident ability, perceived involvement in decision making and the extent to which the homes were resident or institution focused. Results On average, carers intended to spend 27 to 45 minutes per shift providing 1:1 care. Perceived behavioural control was the strongest predictor of intention (accounting for 34% of the variance). Low resident ability level correlated with low perceived behavioural control and predicted a lower intention to provide 1:1 care. Perceived involvement correlated with perceived behavioural control but was not predictive of intention. Past behaviour retained predictive ability once the theory of planned behaviour components were accounted for. Conclusions Residential carers perceive factors within the resident and the organisation as barriers to 1:1 care. Carers may be less likely to provide 1:1 care to residents with lower ability levels, although methodological limitations restrict the conclusions that can be drawn. Future research could usefully consider the potentially habitual nature of 1:1 care

Evaluation of a French version of A Preventative Curriculum for Anorexia Nervosa and Bulimia in French schools in southwestern Ontario.

This thesis was undertaken to determine the effectiveness of the French version of A Preventive Curriculum for Anorexia Nervosa and Bulimia (Un plan d\u27etudes pour la prevention de l\u27anorexie et la boulimie). The purpose of this study was to determine whether the curriculum produced a change in students\u27 knowledge, attitudes and behavior when a unit was taught over a five day period. Two units of the curriculum were taught, one to grade school students and one to high school students. Before the units were taught, the students were given a pretest for knowledge, attitudes and behavior. The units were taught and the students were then given a posttest which was exactly the same as the pretest. It was found that there was a significant increase in knowledge as a result of exposure to these units of the curriculum. There was no change in students\u27 attitudes and behavior. Teachers were asked to give their reactions to the curriculum. They noted that after exposure to the curriculum, students better understood the importance of healthy eating and were less hung up on dangerous dieting. Teachers found the curriculum to be a valuable resource. Source: Masters Abstracts International, Volume: 34-06, page: 2123. Thesis (M.H.K.)--University of Windsor (Canada), 1995

Understanding and mitigating seabird bycatch in the South African pelagic longline fishery

Seabirds are considered one of the most threatened groups of birds in the world. They face additional mortality both on their breeding islands from introduced predators and at sea by fishing fleets, as fisheries bycatch, as well as other human impacts. Seabird bycatch has negatively affected many seabird populations worldwide, with trawl, gillnet and longline fisheries considered the most destructive to seabird populations. Seabird bycatch from trawl and gillnet fisheries has been significantly reduced in recent years, but large numbers of seabirds are still killed annually by longline fisheries. Of the two types of longline fisheries (demersal and pelagic), pelagic longlining is considered the most harmful to seabirds as lines remain closer to the surface for longer periods than demersal longlining, and it is harder to weight lines to ensure rapid sinking beyond the depth they are accessible to birds. Seabirds are killed when they swallow baited hooks and consequently drown. Despite the large number of studies investigating seabird bycatch from pelagic longline fisheries, there remain gaps in our understanding of seabird bycatch from pelagic longline fisheries. This thesis addresses some of these knowledge gaps and makes recommendations as to how seabird bycatch from pelagic longliners can be reduced at both a local and global scale. Chapters 2 and 3 investigate the factors affecting seabird bycatch from pelagic longliners off South Africa, provide a summary of seabird bycatch from the fishery for the period 2006–2013 and quantify the structure of seabird assemblages associated with pelagic longline vessels off South Africa. This was achieved by analysing seabird bycatch data collected by fisheries observers as well as data from sea trials onboard pelagic longliners. Seabird bycatch by pelagic longliners off South Africa over the 8-year study period has been significantly reduced from the 8-year period (1998–2005), mainly driven by a significant reduction in seabird bycatch rates from foreign-flagged vessels, which are responsible for c. 80% of fishing effort off South Africa. Seabird bycatch rates from South African vessels still remain high, four times higher than the interim national target of < 0.05 birds per 1000 hooks. The species composition of seabird bycatch off South Africa is best explained by an understanding of the structure of the seabird assemblage associated with longline vessels. For most species, bycatch and attendance ratios were similar, but for some species such as shy-type and black-browed albatrosses there were large mismatches, likely caused by differences in foraging behaviour and foraging dominance hierarchies. In Chapters 4 and 5 the foraging ecology of the most commonly recorded bycatch species off South Africa, the white-chinned petrel (Procellaria aequinoctialis), is investigated. An understanding of the foraging ecology of commonly recorded bycatch species enhances our understanding of seabird bycatch and helps to improve the design of current and future mitigation measures. The year-round movements of white-chinned petrels from Marion Island were investigated with Global Location Sensors (GLS loggers) and GPS loggers. Adult white-chinned petrels undertake only limited east-west movements of, with all birds remaining between southern Africa and Antarctica. These results strengthen the theory that there is limited spatial overlap year-round between white-chinned petrel populations from South Georgia, the southern Indian Ocean islands and New Zealand sub-Antarctic islands, suggesting that these populations can be managed as separate stocks. The diving behaviour of white-chinned and grey petrels (P. cinerea), another common bycatch species in Southern Ocean longline fleets, were examined with the use of temperature-depth recorders (TDRs), deployed on birds from Marion Island and Gough Island. My study was the first to analyse TDR dive data from any Procellaria petrel, and recorded them reaching maximum dive depths of 16 and 22 m, respectively. Current best practise suggests that baited hooks be protected to a depth of 5 m by bird-scaring lines, but my results suggest this depth should be increased to at least 10 m. Although line weighting is a proven mitigation measure to reduce seabird bycatch from pelagic longliners, fishers have concerns that it will compromise fish catches, crew safety and operational efficiency. In Chapter 6 I analyse line weighting data from trials onboard three pelagic longline vessels, to address the concerns of fishermen. My results show that sliding leads can be incorporated into pelagic longline fisheries without compromising fish catch, crew safety or operational efficiency. I thus recommend that sliding leads be used on pelagic longline vessels fishing off South Africa. By incorporating studies investigating the factors affecting seabird bycatch, seabird foraging ecology and the efficacy of seabird bycatch mitigation measures, my thesis has broadened our understating of seabird bycatch from pelagic longliners and makes meaningful recommendations to further reduce bycatch, both locally and globally. Although seabird bycatch rates have declined off South Africa, through the use of a number different mitigation measures, they still remain higher than the South African national target and thus more work is needed to achieve this target. To reduce seabird bycatch from pelagic longliners to acceptable levels, studies from the world's various longline fleets needs to be considered and improved upon, with seabird conservationists and fishermen working together to achieve this goal

Alien Registration- Cameron, Margaret (Portland, Cumberland County)

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