Sand trapping in ebb tidal deltas at New Zealand's inlets 

Hicks, D. M.; Hume, T. M. 

1992 

 

 

Article in journal 

The ebb and flood tidal deltas, the ocean and bay shoals of sand at tidal inlets, act as sinks for sand derived from the adjacent beaches and the inner shelf. In the response to the need to evaluate coastal sedimentary budgets and assess the availability of sands for industrial supply and beach nourishment, sand volumes in ebb tidal deltas on the North Island coast were estimated and the factors controlling storage investigated. Three basic, albeit transitional, ebb tidal delta shapes were observed. The sand volumes in the deltas ranged over 5 orders of magnitude, from 3.8 x 10/sup 4/ cu. m. at the Whitianga inlet to 1.2 x 10/sup 9/ cu. m. at the Manukau inlet. Morphological and empirical analysis showed that the quantity of sand stored and the shape of the sand body was determined by the tidal prism, the configuration of headlands at the tidal inlet, the alignment of the outflow jet with respect to the shoreline, the wave climate, and the amount of littoral drift. (auths.) 

 

Kaipara harbour; inlets; deltas; transport; whitianga; tidal prism; tidal currents; sands; manukau harbour; Biogeophysical