The palaeoecology of the lower Leintwardinian (Upper Silurian) of the Welsh borderlands and Wales

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Government and public information in the political system : a study of formation and systemic relationships, with particular reference to the Israeli political system, and appropriate comparison with the United Kingdom

Government information organisation and processes are studied in limited aspects, often as public relations. This thesis attempts to present a comprehensive view of them in contexts of theoretical concept and real-world government. A distinction is made between government and public information. Hypotheses are formulated to account for systemic differences, in terms of government constraints from a position of information superiority on the extent of countervailing power distributed to the public with information. Influences on inputs, conversion and outputs demonstrate the extent of mediation which information undergoes within government. Transfers to the public are subject to further mediation in direct and indirect communication channels. Media, in symbiotic relationship with government, dominate transfer of political information. Discussion is mainly in terms of competitive political systems; but the influence of political structure is noted. Government and public information are examined within the illustrative real-world example of Israel. Influences of history, structure, standards and government and public attitudes are noted. Systemic disarticulations in output and feedback are discussed and case details given of consequent information defects. Comparison with the United Kingdom emphasises disparities in government and public information which can exist between politically competitive systems. No decisive relationship to stability is apparent. Theoretical concepts of response and steering of the political system are discussed with the aid of a political communications model. The cycle of information input, output and feedback has apparent discontinuities in terms of constraints in reception, diffusion through media, and thus in feedback, at the public extreme, and of response and steering within government, suggesting limitations in the continuous relationship implied in theoretical models. An alternative framework of assessment is suggested as an indicator of stability. Influences for change are noted, in access and outreach development. Antithetical tension within the government / media symbiosis suggests possible alternative government / public communications

Are there "black holes" in carbonate deposystems?

The likelihood that extensive dissolution of aragonite (and high magnesian calcite) takes place during very early burial, even in relatively shallow tropical settings, has wide implications for interpreting and modelling ancient limestones. Some low energy environments may constitute net sinks (“black holes”) for carbonates. If this is the case attempts to model sediment budgets and develop depth-productivity profiles for carbonate systems require as yet unavailable quantitative data on the effects of these processes. We query whether the established trends of diminishing carbonate productivity with depth could, for some settings such as ramps, be in part an artifact of selective, offshore dissolution more than simply due to reduced benthic production. Many fossil assemblages from low energy settings may be limited to refractory (residual) skeletal elements, which limits our ability to make palaeoenvironmental determinations: some important carbonate grain producers such as the green algae may have been especially prone to early dissolution. The possibility exists that what is now mud-grade carbonate in low energy deposits may not represent original material deposited from suspension but could represent transformed aragonite from in situ production by the skeletal fauna. The selective removal of labile aragonitic (and high Mg calcite) components could produce sediments that appear to have had the composition of cool water types, and the reduced diagenetic potential of many Palaeozoic and cool water carbonates could be a consequence of the effects of early aragonite dissolution rather than due to differences in primary (depositional) composition

Are there "black holes" in carbonate deposystems?

The likelihood that extensive dissolution of aragonite (and high magnesian calcite) takes place during very early burial, even in relatively shallow tropical settings, has wide implications for interpreting and modelling ancient limestones. Some low energy environments may constitute net sinks ("black holes") for carbonates. If this is the case attempts to model sediment budgets and develop depth-productivity profiles for carbonate systems require as yet unavailable quantitative data on the effects of these processes. We query whether the established trends of diminishing carbonate productivity with depth could, for some settings such as ramps, be in part an artifact of selective, offshore dissolution more than simply due to reduced benthic production. Many fossil assemblages from low energy settings may be limited to refractory (residual) skeletal elements, which limits our ability to make palaeoenvironmental determinations: some important carbonate grain producers such as the green algae may have been especially prone to early dissolution. The possibility exists that what is now mud-grade carbonate in low energy deposits may not represent original material deposited from suspension but could represent transformed aragonite from in situ production by the skeletal fauna. The selective removal of labile aragonitic (and high Mg calcite) components could produce sediments that appear to have had the composition of cool water types, and the reduced diagenetic potential of many Palaeozoic and cool water carbonates could be a consequence of the effects of early aragonite dissolution rather than due to differences in primary (depositional) composition

How far did feedback between biodiversity and early diagenesis affect the nature of early Palaeozoic sea floors?

Latest Precambrian to Early Palaeozoic biosphere evolution triggered changes in early diagenesis and carbonate precipitation which fed back to biodiversity through colonization of hard substrates. Progressive increase in the depth and intensity of bioturbation and bio-irrigation lowered the zone of early carbonate cementation in the uppermost sediment column. This firstly led to a decline in the abundance of the flat-pebble conglomerates which had been a common feature of Cambrian and Early Ordovician successions, replaced by the peak and subsequent decline in the Palaeozoic abundance of submarine hardgrounds. The availability of very widespread lithified sea floors in shallow subtidal settings during the Ordovician promoted a rapid expansion in sclerobiont diversity and contributed to the Great Ordovician Biodiversification Event

The Mg/Ca–temperature relationship in brachiopod shells: calibrating a potential palaeoseasonality proxy

Brachiopods are long-lived, long-ranging, extant organisms, of which some groups precipitate a relatively diagenetically stable low magnesium calcite shell. Previous work has suggested that the incorporation of Mg into brachiopod calcite may be controlled by temperature (Brand et al., 2013). Here we build upon this work by using laser ablation sampling to define the intra-shell variations in two modern brachiopod species,Terebratulina retusa (Linnaeus, 1758) and Liothyrella neozelanica (Thomson, 1918). We studied three T. retusa shells collected live from the Firth of Lorne, Scotland, which witnessed annual temperature variations on the order of 7 °C, in addition to four L. neozelanica shells, which were dredged from a water depth transect (168–1488 m) off the north coast of New Zealand. The comparison of intra-shell Mg/Ca profiles with shell δ<sup>18</sup>O confirms a temperature control on brachiopod Mg/Ca and supports the use of brachiopod Mg/Ca as a palaeoseasonality indicator. Our preliminary temperature calibrations are Mg/Ca = 1.76 ± 0.27 e<sup>(0.16 ± 0.03)T</sup>, R<sup>2</sup> = 0.75, for T. retusa and Mg/Ca = 0.49 ± 1.27 e<sup>(0.2 ± 0.11)T</sup>, R<sup>2</sup> = 0.32, for L. neozelanica (errors are 95% confidence intervals)

Adopting Product Modularity in House Building to Support Mass Customisation

Product modularity is a concept that can contribute to the improvement of product quality and production efficiency in house-building. However, there is a lack of consensus in the literature on the concepts that define product modularity. Furthermore, little attention has been given to the differences between building construction and manufacturing, for which product modularity was originally developed. This research aims to address that gap by adapting the conceptualization of product modularity so that it can effectively be used in the house-building industry. The methodological approach adopted in this study was Design Science Research, and two empirical studies were carried out on construction companies based in Brazil and in the U.K. Those studies are used to illustrate the applicability and utility of the proposed concepts and tools. Research findings indicate that the adoption of product modularity concepts results in benefits to both traditional construction technologies and prefabricated building systems

Geometric and depositional responses of carbonate build-ups to Miocene sea level and regional tectonics offshore northwest Australia

The geometric and depositional responses of isolated carbonate build-ups to Miocene sea-level change and regional tectonics was investigated using a combination of 3D seismic and borehole data from the Browse Basin, North West Australia, and outcrop information from the Cariatiz Reef, southeast Spain. The interpreted seismic volume documents five (5) Miocene sequence boundaries and five (5) main seismic facies. Seismic attribute analyses proved a highly effective tool for interpreting carbonate facies but, when compared with outcrop information from southeast Spain, data are limited to large-scale features of scales beyond 16.4 m vertically and 18.75 m horizontally. Hence, this work clearly shows that estimations of reservoir potential are significantly underestimated if based on seismic data alone. As a corollary of the structural analysis in this work, growth patterns suggest Messinian structural partitioning across the Browse Basin, with deformation associated with plate collision focused in preferentially orientated faults - thus only influencing carbonate build-up evolution at a local scale