1620 Robben Island earthquake

The 1620 Robben island earthquake is widely accepted as the oldest recorded earthquake in South African history.[1][2] It reportedly occurred on 7 April 1620, off Robben Island, with a Mercalli intensity of II – IV (Weak–Light). The event was observed by Augustin de Beaulieu, who was leading a fleet of three ships on Table Bay at the time, who recorded "two startling thunderclaps like cannon shots while ship was becalmed near Robben Island" between 6:00 and 7:00.[1][3]

In 2012, Sharad Master of the South African Journal of Science has disputed the accuracy of the recording of the event, concluding that the thunderclaps were very likely atmospheric phenomena. He argues that it was the slight quake which occurred off Cape Town in 1690 which is actually the oldest recorded one in South Africa which can be verified, of Mercalli intensity III.[1]

  1. ^ a b c Master, Sharad. "Oldest 'earthquake' in South Africa (Robben Island, 07 April 1620) discredited". South African Journal of Science. Archived from the original on 16 April 2015. Retrieved 15 May 2015.
  2. ^ Practice of Earthquake Hazard Assessment. DIANE Publishing. 9 March 1993. p. 218. ISBN 978-0-7881-1592-9.
  3. ^ The Earthquake of 29 September 1969 in the southwestern Cape Province, South Africa. Geological Survey, Dept. of Mines, Republic of South Africa. 1974. p. 13.