Tidal signatures in sand prone, tectonically generated Jurassic straits, Scotland ...
The Mid-Jurassic Bearreraig Formation is superbly well exposed on the Isles of Skye and Raasay in NW Scotland. In southern Skye the Bearreraig displays a spectacular, cyclical hierarchy of sand rich, tide-generated bedforms: 1. Upward thickening to thinning compound and compound-compound trough cros...
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| Format: | Thesis |
| Language: | English |
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The University of Texas at Austin
2006
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| Online Access: | https://dx.doi.org/10.26153/tsw/11633 https://repositories.lib.utexas.edu/handle/2152/84661 |
| Summary: | The Mid-Jurassic Bearreraig Formation is superbly well exposed on the Isles of Skye and Raasay in NW Scotland. In southern Skye the Bearreraig displays a spectacular, cyclical hierarchy of sand rich, tide-generated bedforms: 1. Upward thickening to thinning compound and compound-compound trough cross-sets (3D dunes) up to 2.5m thick 2. Compound trough cross-sets (3D dunes) up to 10m thick 3. Upward thinning, simple and compound planer cross-sets (2D dunes) up to 50cm thick Tectonically-generated sequences (up to 140m thick) consisting of these three dune types can be recognized within the formation. Sedimentation occurred in NNE-SSW-aligned, North Skye/Raasay and South Skye half-grabens, defined by Aalenian-Bajocian faulting associated with the initial opening of the North Atlantic. SSW oriented (S. Skye) and NNE oriented (N. Skye/Raasay) fault-parallel paleocurrent directions (indicative of basin separation) suggest that the faults were active and had enough topographic expression to enhance the tidal ... |
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