Present address: The University Centre in Svalbard, PO Box 156, N-9171 Longyearbyen, Norway.
Architecture of vertically stacked fluvial deposits, Atane Formation, Cretaceous, Nuussuaq, central West Greenland
Article first published online: 12 MAY 2010
© 2010 The Authors. Journal compilation © 2010 International Association of Sedimentologists
Volume 57, Issue 5, pages 1280–1314, August 2010
How to Cite
JENSEN, M. A. and PEDERSEN, G. K. (2010), Architecture of vertically stacked fluvial deposits, Atane Formation, Cretaceous, Nuussuaq, central West Greenland. Sedimentology, 57: 1280–1314. doi: 10.1111/j.1365-3091.2010.01146.x
- Issue published online: 9 JUL 2010
- Article first published online: 12 MAY 2010
- Manuscript received 29 July 2008; revision accepted 5 January 2010
- Fluvial architecture;
- incised valley;
- Nuussuaq Basin;
Excellent exposures of thick, multistorey, fluvial deposits from the deltaic Atane Formation on south-east Nuussuaq, central West Greenland, show the architecture of up to 100 m thick continuously aggrading fluvial depositional complexes. The succession comprises vertically stacked channel belt sandstones separated by thin floodplain deposits, with little to no incision between storeys. Architectural elements and palaeocurrent patterns of channel deposits indicate deposition in large, relatively stable, low-sinuosity rivers, probably located within an incised valley. Gradual transitions from channel to floodplain deposits accompanied by a gradual change from floodplain to spillover sand suggest avulsion on the floodplain as a possible mechanism for the vertically alternating channel and floodplain deposits. Despite its relative proximity to contemporaneous sea-level (ca 35 km upstream from the palaeo-shoreline) the depositional complex is entirely non-marine. The aggrading nature of the deposits suggests a continuously rising base level coupled with a high and steady sediment supply. Vertical alternations between floodplain and channel deposits may be forced by subtle interruptions in this balance or autocyclic mechanisms on the floodplain. This study provides an example of aggrading lowstand/non-marine transgressive systems tract deposits.