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- Ahlberg, Anders, et al.
(författare)
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Enigmatic Late Cretaceous high palaeo-latitude lonestones in Chukotka, northeasternmost Asia
- 2002
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Ingår i: GFF. - : Informa UK Limited. - 2000-0863 .- 1103-5897. ; 124:4, s. 197-199
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Tidskriftsartikel (refereegranskat)abstract
- Well-rounded cobbles were encountered within a low-energy restricted marine organic-rich deposit of latest Cretaceous age in Chukotka, NE Asia. The clasts are hydrodynamically incompatible with the inferred quiet depositional environment of the host sediment. Driftwood capable of tree-rafting, glacial striations, gastrolith clast clustering, and disrupting clast impact impressions typical of volcanic ejecta were absent, as were signs of traction currents. If indeed ice-rafting is responsible, this supports recent climate models and palaeobotanical data which favour seasonal marine ice cover of high northern latitudes over a wide span of boundary conditions.
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