Demarcation of the boundary between Middle Devonian Upper Stromness Flagstone and Rousay Flagstone formations in Westray, Orkney
| Autor: | David Leather |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Thursius
010506 paleontology biology Geology Biozone Structural basin 010502 geochemistry & geophysics biology.organism_classification 01 natural sciences Devonian Boundary (real estate) Paleontology visual_art visual_art.visual_art_medium Geological survey Flagstone Osteolepis 0105 earth and related environmental sciences |
| Zdroj: | Scottish Journal of Geology. 53:53-61 |
| ISSN: | 2041-4951 0036-9276 |
| DOI: | 10.1144/sjg2017-007 |
| Popis: | The only official maps to show a boundary between the Middle Devonian Stromness and Rousay Flagstones on Orkney are those published by the Geological Survey in 1932 and 1935. Since then, the difficulties of defining and locating this boundary have challenged many workers in the Orcadian Lake Basin. In 2015, the introduction of biozones by Uisdean Michie, based on fossil fish, and the recent discovery in Westray of the zone fossils Osteolepis panderi and Thursius pholidotus in a prominent fish bed across the island, has permitted the boundary for the base of the Rousay Formation to be determined in that part of Orkney. It is suggested that other characteristics of the fish bed of this rhythmic cycle of sediments, together with those in adjacent cycles, may be used as a marker for further correlation and mapping across the basin. |
| Databáze: | OpenAIRE |
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