The December 26, 2004 Indian Ocean Tsunami: Initial Findings on Tsunami Sand Deposits, Damage, and Inundation in Sri Lanka

Based on Survey Conducted January 9-15, 2005

A Cooperative Study by:

• United States Geological Survey (USGS)
• Earthquake Engineering Research Institute (EERI)
• National Science Foundation (NSF)
• Geological Survey and Mines Bureau of Sri Lanka
• GeoEnvironmental Consultants of New Zealand

Photo taken in Kulmunai Kuddi on Sri Lanka's east coast. View a panorama of this location.
 

Introduction

Location of Sri Lanka and Indian Ocean on a global map.

On December 26, 2004 the deadliest tsunami in the history of the world hit Sri Lanka, triggered by a massive earthquake of moment magnitude 9.0--the largest earthquake recorded worldwide in 40 years. (See also, the USGS earthquake summary; FAQs about the earthquake; and “Tsunami Generation from the 2004 M=9.1 Sumatra-Andaman Earthquake”.) The tsunami was observed worldwide.

Hardest hit were Sumatra (death toll greater than 170,000), Sri Lanka (death toll greater than 31,000), Thailand, and India. From January 9-15, a multi-national team of scientists visited Sri Lanka to document the effects of the tsunami and provide government officials a summary of preliminary results of the surveys. This was the third group that documented the tsunami in Sri Lanka.

The Geological Survey and Mines Bureau of Sri Lanka was the first scientific agency to respond to the tsunami. They sent four teams to survey the east, south, and west coasts of Sri Lanka. Later, from January 4 to 6, a Japanese team led by Professor Kuwata, Kyoto University, made measurements on the west coast of Sri Lanka. This report presents initial findings from two US Geological Survey scientists, Dr. Bruce Jaffe and Dr. Robert Morton, who were members of a Sri Lanka International Tsunami Survey Team (ITST) that collected data to improve the understanding of the December 26, 2004 tsunami.

The primary goal of the Sri Lanka ITST was to assist Sri Lanka through its scientific expertise, especially in developing new techniques for disaster mitigation and prediction. It our hope that the findings of the Sri Lanka ITST will help in planning for future tsunamis in Sri Lanka and in other tsunami-prone regions of the world.

Sri Lanka International Tsunami Survey Team (ITST)