The Times & The Sunday Times
Defences again proved inadequate when another cyclone struck on April 29, 1991, with winds reaching 140mph during a high tide, producing a storm surge as much as seven metres high. More than 130,000 people were killed.
Megatsunami - Wikipedia
A megatsunami is meant to refer to a tsunami with an initial wave amplitude (wave height) measured in several tens, hundreds, or possibly thousands of meters.
Megatsunamis can be caused by giant landslides and asteroid impacts. Underwater earthquakes do not normally generate such large tsunamis, but landslides next to bodies of water resulting from earthquakes do, since they cause a massive amount of displacement.
The recently discovered undersea Burckle Crater located at the bottom of the Indian Ocean would have caused a megatsunami at the time of impact estimated to be c. 3,000—2,800 BC.
http://ioc3.unesco.org/itic/contents.php?id=22
Banda Aceh, Indonesia, 26 December 2004. (picture of boat on building)
Runup can often be inferred from the vertical extent of dead vegetation, from debris normally found at ground level that are observed stuck on electric wires, in trees, or at other heights, and from water line marks left on building walls. In extreme cases, cars, boats, and other heavy objects have been lifted and deposited atop buildings. Banda Aceh, Indonesia, 26 December 2004. Photo courtesy of C. Courtney, Tetra Tech EMI.
For more technical math see;
Tsunami: the underrated hazard
By Edward Bryant
A Megatsunami on superflat treeless land could go 100 km inland, and even more if it forms a bore on a river. Successive tsunami waves penetrate farther because of the water left by the previous wave. A similar event can occur if the land is in flood before the tsunami occurs
Edited by greentwiga, : No reason given.