Sequence Stratigraphy of Carbonate Shelves with an Example from the Mid-Cretaceous (Urgonian) of Southeast France
- Henry W. Posamentier3,
- Colin P. Summerhayes4,
- Bilal U. Haq5 and
- George P. Allen6
Published Online: 15 APR 2009
Copyright © 1993 The International Association of Sedimentologists
Sequence Stratigraphy and Facies Associations
How to Cite
Hunt, D. and Tucker, M. E. (1993) Sequence Stratigraphy of Carbonate Shelves with an Example from the Mid-Cretaceous (Urgonian) of Southeast France, in Sequence Stratigraphy and Facies Associations (eds H. W. Posamentier, C. P. Summerhayes, B. U. Haq and G. P. Allen), Blackwell Publishing Ltd., Oxford, UK. doi: 10.1002/9781444304015.ch17
Plano, Texas, USA
Washington, DC, USA
St Remy les Chevreuses, France
- Published Online: 15 APR 2009
- Published Print: 17 NOV 1993
Print ISBN: 9780632035489
Online ISBN: 9781444304015
- sequence stratigraphy of carbonate shelves - mid-Cretaceous (Urgonian) of southeast France;
- seismic expression of carbonate platforms;
- carbonate and siliciclastic depositional systems - sensitivity of carbonates to environmental change;
- external controls upon sediment-body geometry;
- systems tracts and dynamics of sedimentation;
- transgressive systems tract of carbonate shelves;
- highstand systems tract of carbonate shelves;
- Hauterivian architecture and sedimentation
Carbonate depositional systems differ fundamentally from their siliciclastic equivalents and these differences have been considered and incorporated to develop new concepts and models for carbonate shelves in open ocean settings. Stratal patterns developed by carbonate platforms can be similar to those reported from siliciclastic settings, but in the majority of cases they are different.
Two systems tracts are associated with falling and lowstands of relative sea level, respectively, and these are: the forced regressive wedge systems tract formed during falling relative sea level, bounded below by the ‘basal surface of forced regression’ and above by the sequence boundary representing the lowest point of sea-level fall, and the lowstand prograding wedge systems tract, developed as relative sea level begins to rise after sequence-boundary formation. This systems tract downlaps the basin-floor forced regression deposits in a basinward direction and onlaps forced regressive wedge sediments on the slope. For many carbonate platforms, lowstand sedimentation is greatly reduced and the position, size and geometry of deposits reflect the inherited foreslope architecture. Two end members of slope exist: low-angle mud-dominated slopes and high-angle grain-supported slopes. Characteristic deposits and stratal patterns are developed upon each type during the lowstand systems tract.
Carbonate transgressive systems tracts can also develop a number of different stratal patterns which reflect the complex interplay of relative sea-level rise, sedimentation rate and environmental change. Two different types of geometric stacking pattern are distinguished: type 1 geometries, developed when the rate of relative sea-level rise is greater than sedimentation, and type 2 geometries, formed when sedimentation rates of shelf margin facies are equal to or greater than rates of relative sea-level rise. The highstand systems tract is the time of maximum productivity of carbonate platforms and is normally associated with rapid basinward progradation. Two different highstand foreslope depositional patterns are distinguished: slope aprons leading to the formation of accretionary margins and toe-of-slope aprons developing along bypass margins.
The differences between carbonate and siliciclastic depositional systems suggest that simple application of previously published sequence-stratigraphic models for carbonate depositional systems to subsurface and surface data can lead to incorrect interpretation of systems tracts, sequences and ultimately relative sea-level curves. The models developed in this paper are used in a sequence-stratigraphic interpretation of the mid-Cretaceous Urgonian carbonate platform of the French Alps where many of the models and concepts developed can be illustrated.