2 September 2008

South Africa: Earthquake Caused Mini Tsunami

Oceanographers believe that an undersea earthquake, followed by a mudslide, in the Atlantic caused the mini-tsunami that damaged factory buildings on the South African west coast recently.

The South African National Sea Rescue Institute (NSRI) says hydrographic readings from Cape Town, Port Nolloth, Luederitz and Walvis Bay show evidence of seismic activity on the night of Wednesday, August 20.

"All activity had ceased by the following day, indicative of the most likely origin being an undersea earthquake resulting in an undersea mudslide," an NSRI statement reads.

"The Port Nolloth hydrographic monitor shows the most extreme variance."

The NSRI was alerted to a sudden change in sea level at a number of places along the west coast on August 21.

Witness reports indicated three sudden tide changes in a matter of six hours.

NSRI's spokesperson Craig Lambinon told The Namibian that the surge was minor, but it dragged a car into the sea and caused damage to factories at St Helena Bay.

Oceanographer Professor Geoff Brundrit, Chairman of the Global Ocean Observing System, initially said there could be three causes of the surge - a mid-ocean earthquake, a mid-ocean slump (similar to a mudslide), or extreme thunderstorms.

Brundrit later said hydrographic monitoring equipment at Walvis Bay showed considerable activity over three days.

This could only point to seismic activity - and earthquake - in the Atlantic Ocean, the NSRI statement said.

NamPort and Namdeb officials told The Namibian that no abnormal tides were detected along the Namibian coastline.

Copyright © 2008 The Namibian. All rights reserved. Distributed by AllAfrica Global Media (allAfrica.com). To contact the copyright holder directly for corrections — or for permission to republish or make other authorized use of this material, click here.

AllAfrica publishes around 2,000 reports a day from more than 130 news organizations and over 200 other institutions and individuals, representing a diversity of positions on every topic. We publish news and views ranging from vigorous opponents of governments to government publications and spokespersons. Publishers named above each report are responsible for their own content, which AllAfrica does not have the legal right to edit or correct.

Articles and commentaries that identify allAfrica.com as the publisher are produced or commissioned by AllAfrica. To address comments or complaints, please Contact us.