DYNAMIC STRATIGRAPHY WORKGROUP

River deltas building the shelves

 

People:

Cornel Olariu, Ron Steel

 

Research Question:

What is dynamic of deltas while building the shelf and the shelf margin prism during successive transgression-regression cycles?

 

This project is using data from modern and ancient delta to continental shelf systems to better understand the role of deltas in sediment dispersal on the shelf, and off the shelf-edge to continental slope and deep water. 

 

Summary of work:

Using the modern global bathymetry data we were able to observe and quantify the variability of morphology of the shelf edge in front of large presently active deltas (see reference below).

Related to delta progradation on the shelf, we observed a different pattern between fluvial, wave and tidal dominated deltas while these prograde on the shelf. Specific pattern progradation of each delta type is controlled by the dominant sedimentary process, and have implication on shelf building and on the entire shelf margin accretion.

 

 

 

 

 

 

 

 

Publications and presentations:

Publications

 

Olariu C., and Steel, R.J., 2009, Influence of Point-Source Sediment-Supply on Modern Shelf-Slope Morphology: Implications for Interpretation of Ancient Shelf Margins, Basin Research, v. 21, p. 484-501.

 

Conference/meeting presentations

 

Olariu, C., and Steel, R.J., 2010, Delta Architecture and Process Variability During Cross-Shelf Transits; Autogenic and Allogenic Responses: AAPG Annual Meeting, New Orleans.

 

Olariu, C., and Steel, R.J., 2008, River Delta Behavior during Cross-Shelf Transits: a Step Forward toward Understanding Three-Dimension Architecture of the Continental Margin, AAPG Annual Meeting, San Antonio, Texas.

 

Olariu, C., and Steel, R.J., 2006, High Sediment-Supply Shelf-break Morphology, 17^th International Sedimentological Congress, Fukuoka, Japan.

 

Figure from Olariu and Steel, 2009: Example of the 3-D bathymetry data (in fron of the Nile) with designated areas in front of and to the side of the river delta. The calculated values related to shelf-slope morphology are reported along the strike direction (see red arrow)