The 1620 Robben island earthquake is widely accepted as the oldest recorded earthquake in South African history. It reportedly occurred on April 7, 1620 off

Robben Island Robben Island ( af, Robbeneiland) is an island in Table Bay, 6.9 kilometres (4.3 mi) west of the coast of Bloubergstrand, north of Cape Town, South Africa. It takes its name from the Dutch word for seals (''robben''), hence the Dutch/Afrik ...

, with a

Mercalli intensity The Modified Mercalli intensity scale (MM, MMI, or MCS), developed from Giuseppe Mercalli's Mercalli intensity scale of 1902, is a seismic intensity scale used for measuring the intensity of shaking produced by an earthquake. It measures the eff ...

of IIIV (''Weak–Light''). The event was observed by

Augustin de Beaulieu Augustin de Beaulieu (1589–1637) was a French general, who in 1619 led an armed expedition to the East Indies composed of three ships (275 crews, 106 cannons) and called the "Fleet of Montmorency", after its sponsor the Admiral Montmorency.''A ...

, who was leading a fleet of three ships on

Table Bay Table Bay (Afrikaans: ''Tafelbaai'') is a natural bay on the Atlantic Ocean overlooked by Cape Town (founded 1652 by Van Riebeeck) and is at the northern end of the Cape Peninsula, which stretches south to the Cape of Good Hope. It was named ...

at the time, who recorded "two startling thunderclaps like cannon shots while ship was becalmed near Robben Island" between 6:00 and 7:00. In 2012, Sharad Master of the ''

South African Journal of Science The ''South African Journal of Science'' is an open access, Multidisciplinarity, multidisciplinary academic journal published bimonthly by the Academy of Science of South Africa. The journal has a 2021 impact factor of 2.134. History The journal w ...

'' 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 Cape Town ( af, Kaapstad; , xh, iKapa) is one of South Africa's three capital cities, serving as the seat of the Parliament of South Africa. It is the legislative capital of the country, the oldest city in the country, and the second largest ...

in 1690 which is actually the oldest recorded one in

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...

which can be verified, of Mercalli intensity III.

References

Earthquakes in South Africa 1620 earthquakes 1620s in South Africa Robben Island Events in Cape Town {{earthquake-stub