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8667240 
Journal Article 
Evolution of the east Burdekin Delta coast, Queensland, Australia 1980-1995 
Pringle, AW 
2000 
1 
Zeitschrift fuer Geomorphologie
ISSN: 0372-8854 
44 
3 
273-304 
WOS:000089973500001 
The Burdekin Delta has been classified as one of the world"s major wave-dominated deltas, when the relative intensities of river, wave and tidal processes are considered. The evolution of the most rapidly changing parr of the east Burdekin Delta coast is examined between 1990 and 1995 as a sequel to earlier research covering the period 1940-1980. Six sets of vertical colour aerial photographs have been analyzed to produce sequences of maps revealing coastal evolution and rates of change. A ground survey of Alva Spit in 1995 including vegetation mapping, is compared to a similar 1980 survey. As shown for the earlier period, tropical cyclones and major Burdekin River floods were responsible for the most rapid coastal change. Three tropical cyclones reached landfall on the Burdekin Delta coast between 1980 and 1995, Cyclone Charlie (1988), Cyclone Aivu (1989) and Cyclone Joy (1990), with each producing high energy events in terms of wind, waves, storm surges and rainfall leading to river floods. The maximum river flood of 29,824 cumecs instantaneous maximum and 1,699,057 Mi daily volume at the delta was produced on 3-4 February 1991 by a rain depression during the especially active 1990-1991 wet season. The model of coastal evolution proposed for the earlier 1940-1980 period is tested for the subsequent 15 years. The Burdekin River continued to supply sediment to the coast at highly variable rates, seasonally and annually, with major floods initially breaching coastal spits, barriers and bars, before depositing large quantities of sediment in the intertidal and subtidal zones. Subsequently the dominant south-east trade winds and associated waves and longshore currents moved this sediment northwards by lengthening spits and bars at up to a maximum rate of 375 my(-1) at Kalamia Spit 1991-1993. Superimposed on the northward movement was a westward movement by wave washover and aeolian processes which was Seen especially clearly at Alva Spit as it welded on to the main coastline. Partly off-setting this, mangroves extended seawards in the lee of the spits and bars.