Inner shelf to shoreface hummocky sandstone bodies with evidence for geostrophic flow in the Lower Cretaceous, West Greenland

Helle H. Midtgaard

Research output: Contribution to journalArticleResearchpeer-review


Hummocky sandstone bodies were deposited on the margin of an Early Cretaceous rift basin in an overall progradational inner-shelf to lower-shoreface unit. Excellent outcrops of this unit permitted a detailed study of sedimentary structures and paleocurrents in relation to sandstone geometries. The sandstone bodies are lensoid and 0.5-4 m thick with lateral extensions from a few meters to more than 30 m. Laterally they pinch into thin sandstone sheets that continue for at least 130 m along the entire outcrop or swell within a distance of 20-30 m to form another sandstone lens. The lower boundaries are sharp with local erosional relief up to 1 m. Hummocky cross-stratification, wave-ripple cross-lamination, and low-angle cross-stratification are closely interbedded within the sandstone. Laminated mudstone beds (10-60 cm thick) separate the sandstone bodies and are generally continuous over the entire length of the outcrop. Sedimentary structures in the sandstone bodies were produced by high-energy wave-generated oscillatory currents and unidirectional geostrophic currents. Vertical stratification successions from individual storm events reflect deposition during both increasing storm-current velocity succeeded by waning-storm deposits and, more typically, waning-storm facies successions. Deposition of the unusual vertical successions was probably controlled by an episodically high sediment supply. The local presence of the hummocky sandstone bodies on a regional scale was controlled by a paleogeographic setting where the bathymetric contours locally caused geostrophic currents to decelerate.
Original languageEnglish
Pages (from-to)343-353
Number of pages11
JournalJournal of Sedimentary Research
Issue number2
Publication statusPublished - 1 Mar 1996
Externally publishedYes


  • sedimentology
  • shoreface
  • sandstone
  • geostrophic flow
  • Lower Cretaceous
  • West Greenland

Programme Area

  • Programme Area 3: Energy Resources


Dive into the research topics of 'Inner shelf to shoreface hummocky sandstone bodies with evidence for geostrophic flow in the Lower Cretaceous, West Greenland'. Together they form a unique fingerprint.

Cite this