New Field Evidence of Coseismic Coastal Uplift during the December 2004 Earthquake, North Andaman Island

This report documents ground uplift of a part of the eastern coast of North Andaman Island during the December 2004 earthquake. Emergence of a part of fringing coral reef above the high tide level has been recorded from the Kahpur beach. The newly emergent part of the coral reef is -75m long, -25m wide and trends ESE paralleling the trend of the shore line. The study records appearance of a -600m long and 200m wide tombolo joining the Smith Island to the Ross Island off the eastern coast of North Andaman Island. Before the December 2004 earthquake it was a sand bar that emerged only during the low tides. Vertical movement of 0.4m is calculated for the Kahpur beach while that between the Smith and Ross Islands is 0.7-0.8m.