SAND SPIT EVOLUTION AT THE KEN INLET AND PHAN INLET, CENTRAL VIETNAM

Abstract

 This study presents the sand spit evolution at two typical tidal inlets in central Vietnam by using the long-term remote sensing image data. The sand spit geometric characteristics and the elongation rate, especially sand spits breaching phenomena for the Ken Inlet in Ha Tinh province and Phan Inlet in Binh Thuan province were quantified. Sand spit elongation at Ken Inlet was at a stable rate of about 65 m/y. Whereas, the sand spit elongation rate in Phan Inlet developed very quickly with an average speed of about 185 m/y. In addition, three breaching occurrences of the sand spit in Phan Inlet have been observed in the periods of 1990-1991, 1998-1999, and 2014-2015. The longshore sediment transport rates along the Phan Inlet were almost constant during these three periods. The averaged longshore sediment transport rate at Phan Inlet were estimated around 145,000 m³/y, while Ken Inlet was about 135,000 m³/y.