Geologists hunt for ancient tsunamis in the BVI
By Department of Disaster Management, BVI
Tue, 25 Mar 2008, 13:43
Tortola, March 25, 2008 (DDM) A team of US research geologists spent the last two weeks in the Territory conducting an initial paleoseismic study of Anegada. Dr. Brian Atwater with the United States Geological Survey (USGS) and Dr. Martitia Tuttle with M. Tuttle & Associates were trying to determine if the Puerto Rico Trench can produce magnitude 9 earthquakes and trans-Atlantic tsunamis. They were searching for indicators of past earthquake activity such as faults, tsunami deposits, liquefaction features and changes in land levels.
According to Dr. Atwater, "Anegada was chosen for this project because of its proximity to the Puerto Rico Trench and because the land is less developed than other islands, therefore a record of pre-historic earthquakes, if it exists, is more likely to be preserved."
Following the conclusion of their reconnaissance the Geologists reported on their findings at the DDM. According to Dr. Tuttle, they found an amazing collection of signs that suggest that there had been a flood from the sea within the last 1000 years. The evidence includes sand that apparently moved a mile inland. "There is good evidence that our findings could be the traces of the 1755 Lisbon tsunami that originated offshore of Portugal", she said.
The geologists were very intrigued by the clues they unearthed and hope that they can return for additional research.
"There is a sea flood that is recorded in the geological record on Anegada and we need to better understand it. We need to look further back in the geologic record to determine how often this phenomenon occurs" Dr. Tuttle concluded.
The geologists voiced thanks to BVI residents and government agencies that provided useful information and guidance, especially Anegada elders who provided vivid recollection of the sea flood from Hurricane Donna in 1960.
The funding for this research was provided by the U. S. Nuclear Regulatory Commission, which is responsible for power-plant safety. The US NRC is interested in finding out if there is a tsunami hazard at sites of proposed nuclear power plants on the U.S. Atlantic seaboard.
Department of Disaster Management
#3 Wailing Road MacNamara
Tortola, British Virgin Islands
Ph. 284-494-4499 Fax: 284-494-2024
E-Mail: bviddm@surfbv.com
