The base of the lighthouse was 5 m above sea level when constructed in 1972 . After the tsunami , the sea rose and the base was less than a metre above the sea level , showing over 4 meters of sea floor subsidence . It has been observed that the sea is slowly retreating back to its original position and the subsidence has decreased as the ocean floor slowly bounces back partially , a similar drop and rise due to crustal decompression and re compression was observed in the 2011 Tōhoku earthquake and tsunami on Honshu . Indira point was mostly submerged
2011 Tōhoku earthquake and tsunami
2011 Tōhoku earthquake and tsunami
Great Nicobar Island