[HCG25-P06] Sedimentology, stratigraphy and timescales of flood deposits in the Mekong River Delta.
Keywords:Floodplain , Mekong
The aim of this study is to improve understanding of the timing and depositional processes of floodplain deposits in the Cambodian tract of the Mekong River. This will be achieved through the fulfilment of four research objectives: (i)detailed sedimentary-stratigraphic analysis of the characteristics and, if possible, preserved geomorphic form, of ancient flood deposits at several outcrop locations in the Mekong River Basin (Cambodia); (ii)age-dating of studied successions, using OSL dating, in order to quantify temporal frequency and preservation timescales of fluvial overbank successions in the study area; (iii)analysis of satellite data within the study area to constrain annual–decadal geomorphic change in the fluvial overbank area and ground truth these interpretations using core and outcrop (river terrace) data; (iv) linking the interpreted yearly–decadal hydrodynamic and planform geomorphic changes to the longer timescale stratigraphic record and understand the preservation potential of flood events into the geological record.
This study provides information on natural functioning of floods of the Mekong: frequency and scales, and impacts on natural levees and floodplains. Constraining the timescales over which the geomorphological and sedimentary deposits within fluvio-deltaic overbank areas form, and exploring the applicability of modern analogues of river flood deposits to understanding ancient fluvial overbank successions, would be of use to a wide community of sedimentologists that study modern systems and ancient fluvial-deltaic depositional systems.