Distinction between the Storegga tsunami and the holocene marine transgression in coastal basin deposits of western Norway
✍ Scribed by Stein Bondevik; John Inge Svendsen; Jan Mangerud
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 481 KB
- Volume
- 13
- Category
- Article
- ISSN
- 0267-8179
No coin nor oath required. For personal study only.
✦ Synopsis
Many coastal lakes were inundated by both the Storegga tsunami (7000 14 C yr BP) and the mid-Holocene sea-level rise (the Tapes transgression) in western Norway. The tsunami eroded lake bottoms and deposited graded and/or massive beds of sand, rip-up clasts, and coarse plant material. By contrast, when the rising sea entered the lakes, it deposited only gyttja, silt and fine sand, without causing much erosion of the underlying lake sediments. Storegga tsunami deposits in some coastal lakes were interpreted previously as ordinary marine sediments from the Tapes transgression. Our reinterpretation of these deposits shows that the transgression maximum phase was reached after 6500 yr BP, more than 1000 yr later than previously inferred for the coast of Sunnmøre. The new data cannot be combined in a shoreline diagram without showing the 6000 yr BP and 7000 yr BP shorelines as slightly warped.