Rippon, J H (1997) Variations in tectonic style and setting in British coalfields. Doctoral thesis, Keele University.

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Abstract

British Carboniferous coalfield datasets are used for mapping, analysis, and modelling of depositional and structural patterns, through a significant stratigraphical range and across a variety of tectonic settings.
Westphalian depositional patterns are re-interpreted using channel axis orientations. Major flows were northeasterly into northeast Britain, westerly into the Pennine Basin, and southwesterly through South Wales. Most systems prograded into freshwater lakes. Tectonic depocentres had little effect on channel pathways, but significant effects on net depositional thicknesses, and sandstone and coal connectivity patterns. Varying depositional controls are evaluated, and a complex model is proposed, integrating these; simple sequence stratigraphical interpretations are inappropriate. Many sulphur variations in the coals reflect the channel inflows rather than marine invasions, which were only occasionally important, and were moderated by many local effects.
Structural and sedimentological criteria are proposed for the identification of syn-depositional faulting. Except in Scotland, few syn-depositional movements on specific faults are identifiable from the sedimentary record; some inherited structures continued to grow, as sub-basin bounding faults. These, and large post-depositional structures, generated mosaics of crustal compartments within which fault patterns and jointing orientations demonstrate varied block responses to tectonic events. Coal jointing orientations are considered to record Variscan near, far, and distant field stress, progressively north from South Wales, across central/northem England, and into Scotland.
Recent data on Carboniferous igneous activity are described and interpreted in the Scottish Midland Valley. The Westphalian igneous provinces of the southern Pennine Basin and Oxfordshire are discussed and recommended for further research.
Two case studies illustrate ways in which detailed coalfield data may be used for regional tectonic analysis, namely the evolution of the Kincardine Basin and Ochil Fault in Scotland, and the identification of a specific Variscan thrusting style in Kent.

Item Type: Thesis (Doctoral)
Subjects: Q Science > QE Geology
Divisions: Faculty of Natural Sciences > School of Geography, Geology and the Environment
Depositing User: Lisa Bailey
Date Deposited: 20 Feb 2019 10:17
Last Modified: 20 Feb 2019 10:17
URI: http://eprints.keele.ac.uk/id/eprint/5902

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