The following is a list of notable earthquakes or tremors that have been detected within South Africa.
According to Professor Andrzej Kijko from the University of Pretoria's Natural Hazard Centre, mining can activate natural faults. He believes that 95% of South Africa's earthquakes are caused by mining, especially around the areas of Klerksdorp, Welkom and Carletonville. According to earth science consultant Dr Chris Hartnady, "This part of Africa is in the vicinity of the African Rift system, which is being pulled apart by a few millimetres annually." He says "earthquakes are caused by a slip on a fault line and the release of stored elastic energy" and mining activity can trigger earthquakes. [1]
For earthquakes prior to the modern era, the magnitude and epicentre location are only approximate, and were calculated based on available reports from the time. The magnitude where given is measured using the Richter scale () unless stated otherwise.
Date | Time (SAST) | Epicentre | Region | Depth | Deaths | Notes | |
---|---|---|---|---|---|---|---|
29 September 1969 | Near Tulbagh | Western Cape | 6.3 | 12 [2] | The 1969 Tulbagh earthquake remains the most destructive earthquake in South African history. The earthquake occurred in the Tulbagh area and measured 6.3 on the Richter scale, stronger than that of the 1809 Cape Town earthquake which destroyed a local Milnerton farm. [3] [4] | ||
14 April 1970 | Tulbagh-Ceres-Wolseley area | Western Cape | 5.7 | Second quake [5] | |||
8 December 1976 | Welkom | Free State | 5.2 | 4 | Miners. [6] | ||
26 September 1990 | Welkom | Free State | 4.2 | 2 [6] | |||
9 March 2005 | Stilfontein, | North West | 5.3 | 2 | Miners were killed underground. [7] [8] | ||
28 May 2013 | Near Mbabane | Eswatini | 4.0 | The earthquake was felt in Newcastle and lasted about six seconds. [9] | |||
22 June 2013 | 07:08 | Thabazimbi | Limpopo | 3.9 | 9 km | The earthquake was felt up in the Thabazimbi area. [10] | |
7 July 2013 | 16:52 | Barberton | Mpumalanga | 4.7 | 5 km | The earthquake was felt in the Barberton area. [11] | |
11 November 2013 | University of Johannesburg, Johannesburg | Gauteng | 4.0 | The earthquake was felt as far as parts of northern and southern Johannesburg and lasted for around 10–15 seconds. [12] | |||
2 December 2013 | 21:18 | ~25 km south of Bela-Bela | Limpopo | 4.8 | 5 km | The earthquake was felt as far as Parkhurst and Randburg in Johannesburg, Hartebeespoort Dam in North West, Witbank and KwaMhlanga in Mpumalanga, and Soshanguve near Pretoria. [13] [14] | |
15 June 2014 | 18:16 | Near Orkney | North West | 4.9 | 5 km | The earthquake was felt up to Potchefstroom. [15] | |
5 August 2014 | 12:22 | Near Orkney | North West | 5.5 | 5.0 km | The earthquake was felt as far as parts of Botswana and Durban, it lasted for around 90 sec. The local Council for Geoscience measured the earthquake at 5.5 on the Richter scale, while the United States Geological Survey (USGS) recorded a moment magnitude of 5.4. [16] [17] [18] [19] | |
22 August 2014 | 1:14 | Near Orange Farm | Gauteng | 3.8 | 10 km | The second earthquake in South Africa in less than three weeks. [20] No reports of injuries. [21] The Council for Geoscience (CGS) in South Africa reported an earthquake of 3.8 with two aftershocks occurring within minutes of each other of 3.2 and 2.0 respectively. [22] | |
31 October 2019 | 13:20 | Near Port Shepstone | KwaZulu-Natal | 4.3 | 10 km | The CGS reported an earthquake of a preliminary value of 3.7 on the local magnitude scale. However, the USGS has it logged as 4.3 [23] [24] | |
26 September 2020 | 19:10 | 1600 km SE of South Africa | Western Cape | 6.1 | 10 km | USGS report. [25] Mistakenly reported to have been felt in Cape Town. See below earthquake. | |
26 September 2020 | 20:41 | 12 km W of Paarl | Western Cape | 2.7 | 5 km | Felt by residents in Cape Town area. CGS report. [26] USGS report. [27] | |
27 September 2020 | 09:12 | Durbanville Area, Cape Town | Western Cape | 2.6 | 5 km | Felt by residents in Cape Town area. CGS report. [28] USGS report. [29] | |
17 November 2020 | 00:27 | 41 km S of Saldanha | Western Cape | 3.5 | 5 km | Felt by residents in Cape Town area. CGS report. [30] USGS report. [31] | |
30 July 2021 | 06:30 | Johannesburg | Gauteng | 3.6 | 10 km | Felt by residents in Johannesburg. CGS report. USGS report. [32] | |
5 November 2022 | 14:32 | 23 km from Umvoti Local Municipality | KwaZulu-Natal | 4.6 | 9 km | Felt by residents in Durban area. | |
11 June 2023 | 02:38 | 2 kilometers from Alberton. | Gauteng | 5.0 | 10 km | Felt by residents across the city of Johannesburg and the region as a whole. [33] |
Orkney is a gold mining town situated in the Klerksdorp district of the North West province, South Africa. It lies on the banks of the Vaal River approximately 180 km from Johannesburg near the N12.
The 2007 Bengkulu earthquakes were a series of megathrust earthquakes that struck the Sunda Trench off the coast of Sumatra, Indonesia, with three of magnitude 7 or greater. A series of tsunami bulletins was issued for the area. The most powerful of the series had a magnitude of 8.4, which makes it in the top 20 of the largest earthquakes ever recorded on a seismograph.
A potent magnitude 6.6 Mw intraplate aftershock occurred at 17:16 JST (08:16 UTC) on 11 April, in the Hamadōri region of Fukushima, Japan. With a shallow focus of 13 km (8.1 mi), the earthquake was centred inland about 36 km (22 mi) west of Iwaki, causing widespread strong to locally severe shaking. It was one of many aftershocks to follow the 11 March Tōhoku earthquake, and the strongest to have its epicentre located inland.
The 2011 Kütahya earthquake struck near a populous region of western Turkey at 23:15 EEST (20:15 UTC) on 19 May with a moment magnitude of 5.8 and a maximum Mercalli intensity of VII. With an epicenter just to the east of Simav, it occurred at an estimated depth of 9.1 kilometers (5.7 mi), resulting in strong shaking in much of Kütahya.
The June 2011 Christchurch earthquake was a shallow magnitude 6.0 Mw earthquake that occurred on 13 June 2011 at 14:20 NZST. It was centred at a depth of 7 km (4.3 mi), about 5 km (3 mi) south-east of Christchurch, which had previously been devastated by a magnitude 6.2 MW earthquake in February 2011. The June quake was preceded by a magnitude 5.9 ML tremor that struck the region at a slightly deeper 8.9 km (5.5 mi). The United States Geological Survey reported a magnitude of 6.0 Mw and a depth of 9 km (5.6 mi).
On August 23, 2011, a magnitude 5.8 earthquake hit the Piedmont region of the U.S. state of Virginia at 1:51:04 p.m. EDT. The epicenter, in Louisa County, was 38 mi (61 km) northwest of Richmond and 5 mi (8 km) south-southwest of the town of Mineral. It was an intraplate earthquake with a maximum perceived intensity of VIII (Severe) on the Mercalli intensity scale. Several aftershocks, ranging up to 4.5 Mw in magnitude, occurred after the main tremor.
The 2011 Oklahoma earthquake was a 5.7 magnitude intraplate earthquake which occurred near Prague, Oklahoma on November 5 at 10:53 p.m. CDT in the U.S. state of Oklahoma. The epicenter of the earthquake was in the vicinity of several active wastewater injection wells. According to the United States Geological Survey (USGS), it was the most powerful earthquake ever recorded in Oklahoma until the 2016 Oklahoma earthquake. The previous record was a 5.5 magnitude earthquake that struck near the town of El Reno in 1952. The quake's epicenter was approximately 44 miles (71 km) east-northeast of Oklahoma City, near the town of Sparks and was felt in the neighboring states of Texas, Arkansas, Kansas and Missouri and even as far away as Tennessee and Wisconsin. The quake followed several minor quakes earlier in the day, including a 4.7 magnitude foreshock. The quake had a maximum perceived intensity of VIII (Severe) on the Mercalli intensity scale in the area closest to the epicenter. Numerous aftershocks were detected after the main quake, with a few registering at 4.0 magnitude.
The 2012 Indian Ocean earthquakes were magnitude 8.6 and 8.2 Mw undersea earthquakes that struck near the Indonesian province of Aceh on 11 April at 15:38 local time. Initially, authorities feared that the initial earthquake would cause a tsunami and warnings were issued across the Indian Ocean; however, these warnings were subsequently cancelled. These were unusually strong intraplate earthquakes and the largest strike-slip earthquake ever recorded.
The 2013 Lake Grassmere earthquake was a magnitude 6.6 earthquake that occurred at 2:31:05 pm (NZST) on Friday 16 August 2013. The epicentre was located about 10 km south-east of Seddon, under Lake Grassmere, with a focal depth of 8 km. The earthquake caused significant land damage in the local area, with landslips blocking roads, including the main highway between Blenheim and Christchurch. Buildings in Seddon were damaged, with some being declared uninhabitable. The earthquake was widely felt in both the North and South Islands of New Zealand.
The 1993 Klamath Falls earthquakes took place in Klamath Falls, Oregon, beginning on Monday, September 20 at 8:28 p.m. The doublet earthquake registered respective magnitudes of 6.0 and 5.9 on the moment magnitude scale. The earthquakes were located at a depth of 5.6 miles (9 km) and tremors continued to be felt more than three months after the initial shocks.
The Oklahoma earthquake swarms are an ongoing series of human activity-induced earthquakes affecting central Oklahoma, southern Kansas, northern Texas since 2009. Beginning in 2009, the frequency of earthquakes in the U.S. state of Oklahoma rapidly increased from an average of fewer than two 3.0+ magnitude earthquakes per year since 1978 to hundreds each year in the 2014–17 period. Thousands of earthquakes have occurred in Oklahoma and surrounding areas in southern Kansas and North Texas since 2009. Scientific studies attribute the rise in earthquakes to the disposal of wastewater produced during oil extraction that has been injected more deeply into the ground.
The 2014 Ludian earthquake struck Ludian County, Yunnan, China, with a moment magnitude of 6.1 on 3 August. The earthquake killed at least 615 people, injuring at least 2,400 others. At least 114 people remained missing. Over 12,000 houses collapsed and 30,000 were damaged. According to the United States Geological Survey, the earthquake occurred 29 km (18 mi) west-southwest of Zhaotong city at 16:30 local time (08:30 UTC).
The 2014 Orkney earthquake occurred at 12:22:33 SAST on 5 August, with the epicentre near Orkney, a gold mining town in the Klerksdorp district in the North West province of South Africa. The shock was assigned a magnitude of 5.5 on the Richter scale by the Council for Geoscience (CGS) in South Africa, making it the biggest earthquake in South Africa since the 1969 Tulbagh earthquake, which had a magnitude of 6.3 on the Richter scale. The United States Geological Survey (USGS) estimated a focal depth of 5.0 km (3.1 mi). The CGS reported 84 aftershocks on 5 August and 31 aftershocks on 6 August, with a magnitude of 1.0 to 3.8 on the Richter scale. According to the CGS, the earthquake is the biggest mining-related earthquake in South African history.
An earthquake struck approximately 53 kilometres SSE of the town of Mansfield, in the Victorian Alps of Australia on 22 September 2021, at 09:15 local time. The earthquake measured 5.9 on the moment magnitude scale. The earthquake caused minor structural damage in parts of Melbourne and left one person injured. The earthquake was also felt in New South Wales, Australian Capital Territory, South Australia and Tasmania. The earthquake was substantially stronger than the 1989 Newcastle earthquake that measured 5.6 and killed 13 people.