Late Cenozoic prograding wedges on the NW European continental margin : their formation and relationship to tectonics and climate

• Published in: Marine and Petroleum Geology
• Main Authors: Torbjorn Dahlgren, K.I., Vorren, Tore O., Stoker, Martyn S., Nielsen, Tove, Nygard, Atle, Sejrup, Petter
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Elsevier 2005
• Subjects: Barents Sea; Norway; Tilting; Fennoscandian; Spitsbergen
• Online Access: http://nora.nerc.ac.uk/id/eprint/18313/; http://www.sciencedirect.com/science/journal/02648172

During late Pliocene to Pleistocene times, prominent prograding wedges were deposited along the continental margin of NW Europe, resulting in seaward shelf break migration of up to 150 km. Much of the sediment accumulation occurred marginal to the former mid- to high-latitude ice sheets. The geographical distribution, and stratigraphical and chronological data may suggest that the instigation of the wedges was variously related to tectonic uplift as well as a response to the late Pliocene to Pleistocene climate deterioration and onset of major northern hemisphere glaciations. The onset of wedge growth on the NW UK and Irish margins was initiated at about 4 Ma in response to tectonic tilting of the margin in that region. However, glacially derived sediments here comprise a significant proportion of the wedges, especially since 0.44 Ma. For the Faroe margin, no detailed chronology is available; however, it may be inferred that onset of glacigenic wedge growth here did not post-date that observed on the NW UK and Irish margins. Offshore Norway, wedge growth has largely occurred since ca. 2.7 Ma in response to northern hemisphere glaciations, also recording a major change in sediments transport routes at 0.8–1.1 Ma (reflecting larger Fennoscandian Ice Sheets). Presently, it is uncertain whether the glacigenic wedge growth was preceded by a fluvial phase (in response to uplift) in this area. In the western Barents Sea, an early phase of wedge growth was (glacio) fluvial in character. Off western Spitsbergen, the development was similar to that of the Barents Sea although the glacigenic wedge-growth phase may have started somewhat earlier.