Clinoform deposition across a boundary between orogenic front and foredeep – an example from the Lower Cretaceous in Arctic Alaska
Article first published online: 31 JAN 2013
Published 2012. This arrticle is a U.S. Government work and is in the public domain in the USA.
Volume 25, Issue 3, pages 206–211, June 2013
How to Cite
Terra Nova, 25, 206–211, 2013
- Issue published online: 19 APR 2013
- Article first published online: 31 JAN 2013
- Accepted manuscript online: 28 DEC 2012 06:17AM EST
- Manuscript Accepted: 21 DEC 2012
- Manuscript Received: 22 JUN 2012
The Lower Cretaceous Fortress Mountain Formation occupies a spatial and temporal niche between syntectonic deposits at the Brooks Range orogenic front and post-tectonic strata in the Colville foreland basin. The formation includes basin-floor fan, marine-slope and fan-delta facies that define a clinoform depositional profile. Texture and composition of clasts in the formation suggest progressive burial of a tectonic wedge-front that included older turbidites and mélange. These new interpretations, based entirely on outcrop study, suggest that the Fortress Mountain Formation spans the boundary between orogenic wedge and foredeep, with proximal strata onlapping the tectonic wedge-front and distal strata downlapping the floor of the foreland basin. Our reconstruction suggests that clinoform amplitude reflects the structural relief generated by tectonic wedge development and load-induced flexural subsidence of the foreland basin.