Polyline defining the margin of a former delta. A delta is formed by deposition of sediment transported via river as it enters slower-moving / stagnant body of water such as a marine environment, lake or estuary. Chronological information is presented as calendar age BP. Confidence is defined as follows: 1. High: Sampled feature with good age and palaeoenvironmental control. 2. Sampled feature with poor or none age and palaeoenvironmental control. 3. Constructed by remote sensing data only. 4. Low: Reasonable without any direct evidence.