Publication Abstract

Continental shelf environments

P. Larcombe

This chapter addresses the environmental sedimentology of continental shelves. ‘Continental shelf’ is taken to be the sea floor shallower than about 200 m adjacent to continental landmasses, whose outer margin is marked by the continental slope (e.g. Whitten & Brooks, 1972). In the long-term, continental shelves receive river sediments, with supply to the shelf modulated by catchment (Milliman 2001; Walling & Fang, 2003) and estuarine processes (Dyer 1996, 2000). Some shelves contain major regions of in-situ sediment production, predominantly calcareous in nature, and shelf sediment dynamics are crucial in influencing the nature and fate of shelf sediments. The nature and morphology of continental shelves is controlled by: i) the hydraulic regime, and hence sediment transport; ii) sediment supply, and iii) relative sea-level (Johnson & Baldwin, 1996). Other factors, particularly important for carbonate shelves, are climate, biological interactions with the sediments, seawater chemistry and sediment composition. It is increasingly being acknowledged in management regimes that the surface sedimentary systems are vital to marine ecosystems.

Reference:

P. Larcombe (2006) Continental Shelves. In: Perry, C. and Taylor, K. (Eds.) Environmental Sedimentology. Blackwell Science.  pp. 351-388.