Origin and evolution of interdistributary delta plains; insights from Mekong River delta

Luminescence dating of beach ridges for characterizing multi-decadal to centennial deltaic shoreline changes during Late Holocene, Mekong River delta

“…In the Tra Vinh delta plain, however, the width of delta-front platform appears to have changed ( Fig. 7; Tamura et al, 2012), which may be the result of the millennial-scale evolution. The initial delta progradation appears to have been a transitional state from the low-gradient aggradational delta before 3500 years, after which the clinoform has steepened as the prograding delta became more pronounced.…”

“…Although it is not possible to quantify the progradation of these coasts in detail, the majority of these other delta plains have formed since 1500 years ( Fig. 1B; Tamura et al, 2012). The focal shift of the river sediment supply towards the northeast thus accounts for the declined progradation of the Tra Vinh delta plain (Fig.…”

“…In the Tra Vinh delta plain, central Mekong delta, the beach shoreline was initiated c. 3500 years and has prograded, resulting in a huge delta plain with beach ridges extending up to 50 km inland from the present shoreline. Here we present 32 new OSL age determination from the Tra Vinh delta plain which when combined with the 15 ages reported by Tamura et al (2012) are used to demonstrate the effectiveness of OSL dating for constraining multi-decadal to centennial-scale shoreline changes during the Late Holocene. We further discuss causes of reconstructed changes, and examine implications for the modern shoreline.…”

“…The Mekong River delta, an excellent example of a mixed tide-and wave-dominated delta (Galloway, 1975), has prograded more than 200 km seawards since c. 8000 years (Tamura et al, 2007(Tamura et al, , 2009. Tamura et al (2012), based on 31 OSL ages of beach ridges on several delta plains of the Mekong delta coupled with sediment drill cores and their radiocarbon dates (Ta et al, 2005), clarified the multi-centennial to millennial-scale, three dimensional evolution of the delta. In the Tra Vinh delta plain, central Mekong delta, the beach shoreline was initiated c. 3500 years and has prograded, resulting in a huge delta plain with beach ridges extending up to 50 km inland from the present shoreline.…”

Asymmetry in Holocene river deltas: Patterns, controls, and stratigraphic effects

“…Similarly, the mouth of the tide-and wave-influenced Mekong delta exhibits an asymmetric bifurcation pattern (Fig. 10A;Tamura et al, 2012). The bifurcated Mekong river mouth is wider on the upcurrent side because of strong longshore drift.…”