Mponeng Gold Mine

Last updated
Mponeng
Mponeng-goudmyn, Merafong City-pm, Wesrand-dm, a.jpg
Above-ground operations at Mponeng mine.
Location
South Africa adm location map.svg
Schlaegel und Eisen nach DIN 21800.svg
Mponeng
Location in South Africa
Province Gauteng
Country South Africa
Coordinates 26°26′10″S27°25′50″E / 26.43611°S 27.43056°E / -26.43611; 27.43056
Owner
CompanyHarmony Gold
Website https://www.harmony.co.za

Mponeng is an ultra-deep tabular gold mine in South Africa in the Witwatersrand Basin of the Gauteng Province. [1] Previously know as Western Deep Levels No1 Shaft, the mine began operations in 1986. [2] It is one of the most substantial gold mine mines in world in terms of production and magnitude, reaching over 4 kilometres (2.5 mi) below the surface. [3] [4] At this depth Mponeng takes the title of world's deepest mine from ground level, with aims to deepen the mine beyond 4km in order to reach more reserves. [5] [6] A trip from the surface to its deepest point takes over an hour, but the harsh conditions of the mine did not stop an Ecuadorian marathon runner from completing a half marathon within the mine. [3] [7] Mponeng comes with economic, environmental, societal, and seismic detrimental costs, but mining in South Africa has had a huge effect on the technologies of deep gold mining around the world, making South Africa a pioneering leader in gold-mining technologies. [8]

Contents

Operations

History

As part of the Witwatersrand, the largest gold deposit on earth, Mponeng is the result of the discovery of the basin by European colonizers and settlers. Beginning in the 1850-70s a series of mineral discoveries were made in the area, including those of Pieter Jacobus Marais panning gold from a river and Henry Lewis finding quartz and gold vein on a farm, that led to the Witwatersrand Gold Rush in 1886. [9] These discoveries led to many mining operations and after shaft sinking for about 5 years (1981) Mponeng officially began mining operations in 1986. [10] [11] Before Mponeng, the mine was known as the Western Deep Levels South Shaft or the No1 Shaft; the name Mponeng came into use in 1999. [10]

Liv Shange addresses striking mineworkers in Carletonville during 2012 national strikes. Liv Shange addresses striking mineworkers in Carletonville during 2012 national strikes.jpg
Liv Shange addresses striking mineworkers in Carletonville during 2012 national strikes.

The mine is estimated to be producing until 2029, when reserves may finally run out, the mine has been running since 1986 and has the possibly to run for 43 years. [12] current depths reach roughly 3.8km down, in the coming years of remaining production life of the mine it will likely reach beyond 4.2km depth. [12] The mine has not be running continuously since the day of opening in 1986. A seismic event in March of 2020 resulted in a stoppage of operations due to fatalities. [12] Like many other operations, Mponeng closed due to COVID-19 in May 2020, but has since returned the producing. [12] [13]

Striking in South Africa's mining district was apparent in the 1900s, for example the South African gold mine strike in August 1946. [14] As Mponeng did not start operations until near the turn of the century there has not been many other notable strikes since then, other than 2012. Back in 2012, while AngloGold Ashanti was Mponeng's owner, strikes occurred. [15] The strikes were a combined result of gold and platinum industry-worker issues in South Africa. [15] AngloGold's position on the matter was to maintain safety, peace, and stability. [15] The striking action of 2012 totaled nearly 16% of the total mining workforce of South Africa, not just Mponeng. [16] AngloGold specifically experienced nearly 35,000 workers putting down there tools in the illegal strike. [17] Although not at Mponeng, the strike of 2012 included a wildcat strike at a nearby platinum mine ended with 34 miners dying from police interactions. [16]

Operations and ownership

Harmony Gold, Africa's largest gold producer, purchased Mponeng from AngloGold Ashanti (AGA) in 2020, for approximately $200 million. Harmony Gold also acquired Mine Waste Solutions as they gathered the remainder of AGA's assets in late 2020. [18] As of 2022, all-in costs of production were US$1771/oz (US$1614/Troy oz). Even at near record high gold prices, Mponeng is barely breaking even. [19] Gold is currently worth roughly US$2080/oz (US$1900/Troy oz). [20] Over 5,400 metric tons of rock are excavated from Mponeng each day. [21] Harmony Gold, aside from closures, has kept up operations:

The most recent publication from Harmony Gold outlines their 2023 year production:

Physical conditions

A colony of Desulforudis audaxviator, discovered in the Mponeng gold mine.. See article Life without The Sun for details Desulforudis audaxviator.jpg
A colony of Desulforudis audaxviator, discovered in the Mponeng gold mine.. See article Life without The Sun for details

The temperature of the rock reaches 66 °C (151 °F), and the mine pumps slurry ice underground to cool the tunnel air to below 30 °C (86 °F). [23] A mixture of concrete, water, and rock is packed into excavated areas, which further acts as an insulator. [23] Tunnel walls are secured by flexible shotcrete reinforced with steel fibers, which is further held in place by diamond-mesh netting. [23]

In 2008, researchers looking for extremophile organisms discovered the bacterium Desulforudis audaxviator present within groundwater samples from kilometers deep in the mine. [24] The name 'Audaxviator' comes from the novel Journey to the Center of the Earth by Jules Verne, which means 'descend, bold traveler, and attain the center of the Earth'. [25]

Geology and gold bearing fractures

The mine sits in the Witwatersrand Basin and utilizes 2 horizons: Ventersdorp Contact Reef and Carbon Leader Reef. [26] In the Mponeng mine the Ventersdorp Contact Reef is mainly interbedded quartzite and coarse conglomerates and constitutes only a meter or two of thickness. [27] The Witwatersrand Basin has experienced many surges of thrusting in the past, resulting in abundant fractures. [27] These small faults often correspond to depositional and sediment contacts. [27] It is along these faults that mineralizing fluids flow, which lead to the precipitation or mineralization of gold. [28] This complicated geologic history associates with gold mineralization to a high degree, the Witwatersrand Basin holds nearly a third of gold reserves and is responsible for over 40% of all gold. [27] Mponeng has a proven gold reserve of roughly 46 million ounces (over 1300 tons), that is more than 8x more than the second deepest gold mine 'Driefontein' also located in South Africa. [28]

The gold mineralization is likely related to hydrothermal activity, and occurs in varying lithology of conglomerates, known as the reefs stated above. [27] The stratigraphy that the gold is found in ranges in thickness, from around 10 cm to a 1-meter. [29] Gold is found in these variable thickness layers of pebble lags, stacked fluvial deposits, and other stratigraphy. [29] [27] Mponeng specifically, gold is associated with previously mentioned thrust fracturing and with the following mineralizations:

As with most mines, Mponeng is limited to the structural control of the geology. The VCR mineralization is governed by thrust-fracture systems discussed above, largely from the Lower Kliprivierberg age. [29] The VCR and CLR themselves are around 2.7 billion years old, and have experienced lots of deformation and change. [30] [31]

Environmental impacts

South Africa has been dealing with the effects of mining-related pollution for years; the effects of mining-related environmental damage have been large given that mining is roughly 8% of the South African GDP. [32] In 1998, mining industry contributed nearly 90% of the 533.6 million tons of waste that was produced annually. [33] According to 1998 data, gold mining is the largest single source of pollution in South Africa.[ citation needed ] A large portion of this occurs in the Witwatersrand Basin, home to over 270 tailings storage facilities, covering 18,000 Ha. [33]

Mining creates two main kinds of waste: waste rock piles and tailing storage facilities (TSFs). [33] Waste rock piles are the rock that must be removed in order to reach the ore; for Mponeng, the waste rock piles are consideration due to the mine's depth. [34] Tailings result from the crushing and grinding process of the ore, very fine silt sized material is produced and collected in mounds. Tailings especially come with severe environmental and health issues as they contain potentially hazardous chemicals. [33] Long-term consequences are also of concern, whether the mine activities continue, halt, or a mine is abounded, these TSFs can pose serious risk the surrounding environment. [33] Pollution has been found to persist even after 72 years of mine abandonment. [33]

Beyond the environment, the citizens of the Witwatersrand Basin have been complaining of windblown dust, most of which originates from partially rehabilitated TSFs. [35] Anglo Ashanti began recording meteorological data in 2012 and Harmony Gold has since taken over monitoring after the acquisition in 2020. [35] Citizens are concerned surrounding heavy metal content as well as silica content, as both pose serious health risks (silicosis, tuberculosis, bronchitis, chronic obstructive pulmonary disease (COPD), lung cancer). [36] [37] A study in 2020 found elevated value of silica and uranium in PM10 airborne pollution from TSFs of gold mines in the area. [35]

In South Africa, heavy metal pollution from mining industry is the leading cause of soil and water pollution. [33] The pollution stems from a few sources: [33] [35]

Environmental remediation

Two actions can begin to combat South Africa's pollution issues relating to gold mining, prevention of new pollution and remediation of old. The caveats of prevention and remediation are the fact that both of which are extremely difficult and expensive, neither the mining industry or South Africa could afford a completely turn around on pollution. [33]

Immobilizing the PTEs in the TSFs is a main focus of pollution prevention and control. [33]

Other than prevention and remediation, it has been proposed that in order to protect environments remaining tailings materials should be removed from TSFs if containment is not secure. [38]

Seismicity

Seismicity in mines is common as removing mass amounts of rock can change stress dynamics, especially if pre-existing faults exist. [39] This seismicity is termed 'mining-induced seismicity', caused by the release of elastic strain but are often low moment magnitude. [39] [40] Reaching beyond 1,000 events a day, events of any size pose serious risk to mining operations and employees. It is not uncommon for equipment to be damaged, or have the collapse of drifts and stopes as a result of events. [39] [40]

On December 27, 2007 a dyke within Mponeng experienced a 1.9 magnitude event caused by stress change due to excavation within the mine. In March 2020 Mponeng experienced a magnitude 2 earthquake in which 3 people were killed. [41] In deep mines, vertical stress can reach an astounding 80-100 MPa, equivalent to roughly 10 km under water. [42] [43] [44] [45] Seismicity in deep gold mines is common, and is often induced by mining activities. [40] [46] Two events can be considered: [40]

Most earthquakes at depth are mining related (Type A), typically associated with the beginning of a new stope. [47]

Research

One way to move forward is a better understanding of rock burst and excavation methods. A better understanding can provide better safety protocols. [48] A prominent use of deep mines and their associated, often low magnitude, earthquakes is to connect laboratory scale experiments to real world situations. [49] [50] There is also considerable research trying to understand nucleation of said earthquakes, [49] and whether they work the same as larger earthquakes. [50] In Mponeng, JAGUARS (Japanese-German Acoustic Emissions Research in South Africa) [51] has emplaced a network of accelerometers and piezoelectric acoustic emissions sensors. [49] These sensors can record very small moment magnitude earthquakes, capable of recording events with frequencies from 0.7 kHz to 200 kHz (M<0.5). [47] In a one year period, 2007-2008, nearly 500,000 events were recorded, most of which with low (sub 25 kHz) frequencies. [47] The JAGUARS network in placed below the Ventersdorp Contact Reef, there are eight Acoustic Emissions sensors, two strainmeters, and one triaxial accelerometer that make up the network. [47]

Millan Ludena, 'From Core to Sun'. Guinness World Record Holder. https://www.flickr.com/photos/asambleanacional Millan Ludena en 2017.jpg
Millan Ludena, 'From Core to Sun'. Guinness World Record Holder. https://www.flickr.com/photos/asambleanacional

Released in 2010, the American television show 'Build it Bigger' (Powderhouse Productions) hosted by Danny Forster visited Mponeng Gold Mine. [52]

Millan Ludeña, an Ecuadorian marathon runner, became the first person to run a half-marathon fully underground in the deepest part of Mponeng Gold Mine. A Guinness World Records adjudicator was on hand to document the race and issued the certificate for the deepest half-marathon. [53] Inversely, it became Millan's goal to run as far, and as close to the Sun as he could. Later, after Mponeng, Millan ran up Mt. Chimborazo in Ecuador. [54] Millan has a movie called 'From Core to Sun' released in 2018 about his achievements. [55]

See also

Related Research Articles

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References

  1. Ziegler, Moritz; Reiter, Karsten; Heidbach, Oliver; Zang, Arno; Kwiatek, Grzegorz; Stromeyer, Dietrich; Dahm, Torsten; Dresen, Georg; Hofmann, Gerhard (1 October 2015). "Mining-Induced Stress Transfer and Its Relation to a M1.9 Seismic Event in an Ultra-deep South African Gold Mine". Pure and Applied Geophysics. 172 (10): 2557–2570. doi:10.1007/s00024-015-1033-x. ISSN   1420-9136.
  2. www.harmony.co.za https://www.harmony.co.za/operations/south-africa/underground/mponeng/#:~:text=The%20mine,%20which%20began%20producing,and%203%20740m%20below%20surface. Retrieved 12 March 2024.{{cite web}}: Missing or empty |title= (help)
  3. 1 2 Wadhams, Nick (11 March 2011). "Gold Standards: How miners dig for riches in a 2-mile-deep furnace" (Vol. 19 No. 3 ed.). Wired. p. 42.
  4. "Mponeng Gold Mine, Gauteng". Mining Technology. Retrieved 17 February 2024.
  5. Praveen (11 June 2019). "The top ten deepest mines in the world". Mining Technology. Retrieved 17 February 2024.
  6. Manzi, M. (16 June 2014). "3D Seismic Imaging of the Ghost-Carbon Leader Reef of the World's Deepest Gold Mine - Mponeng Gold Mine, South Africa". EAGE. Proceedings 76th EAGE Conference and Exhibition Workshops. European Association of Geoscientists & Engineers: cp. doi:10.3997/2214-4609.20140511. ISBN   978-90-73834-90-3 via EarthDoc.
  7. Garcia, Sergio (23 September 2017). "Ecuadorian sets record in run 4,000m below surface". www.aa.com.tr. Retrieved 17 February 2024.
  8. Vegter, Ivo (2018). "Why Mining Still Matters". South Africa Institute of Race Relations. 11.
  9. Cairncross, Bruce (4 July 2021). "The Witwatersrand Goldfield, South Africa". Rocks & Minerals. 96 (4): 296–351. Bibcode:2021RoMin..96..296C. doi:10.1080/00357529.2021.1901207. ISSN   0035-7529.
  10. 1 2 Barradas, Sheila. "Mponeng mine, South Africa". Mining Weekly. Retrieved 12 March 2024.
  11. www.harmony.co.za https://www.harmony.co.za/operations/south-africa/underground/mponeng/#:~:text=The%20mine,%20which%20began%20producing,and%203%20740m%20below%20surface. Retrieved 12 March 2024.{{cite web}}: Missing or empty |title= (help)
  12. 1 2 3 4 "Mponeng Gold Mine, South Africa - The World's Deepest Mine" . Retrieved 12 March 2024.
  13. Bongaerts, Dion; Mazzola, Francesco; Wagner, Wolf (14 May 2021). "Closed for business: The mortality impact of business closures during the Covid-19 pandemic". PLOS ONE. 16 (5): e0251373. doi: 10.1371/journal.pone.0251373 . ISSN   1932-6203. PMC   8121299 . PMID   33989322.
  14. James, Wilmot G. (1987). "Grounds for a Strike: South African Gold Mining in the 1940s". African Economic History (16): 1–22. doi:10.2307/3601267. ISSN   0145-2258. JSTOR   3601267.
  15. 1 2 3 McKay, David. "Strikes shut down 40% of SA gold". Business. Retrieved 24 March 2024.
  16. 1 2 Press, RODNEY MUHUMUZA, Associated (4 October 2012). "Striking SAfrican miners find strength in numbers". CNBC. Retrieved 24 March 2024.{{cite web}}: CS1 maint: multiple names: authors list (link)
  17. Smith, David (26 September 2012). "South African's goldmines beset by simmering resentment". The Guardian. ISSN   0261-3077 . Retrieved 24 March 2024.
  18. "Mponeng Gold Mine, South Africa - The World's Deepest Mine" . Retrieved 12 March 2024.
  19. Burron, Ian (13 April 2023). "How Low Can you go? The Challenges of Deep Mining | Geology for Investors". www.geologyforinvestors.com. Retrieved 17 February 2024.
  20. "Gold Statistics and Information | U.S. Geological Survey". www.usgs.gov. Retrieved 16 February 2024.
  21. Wadhams, Nick (11 March 2011). "Gold Standards: How miners dig for riches in a 2-mile-deep furnace" (Vol. 19 No. 3 ed.). Wired. p. 42.
  22. 1 2 3 "Mponeng - Operating Performance FY23". www.harmony.co.za. Retrieved 29 February 2024.
  23. 1 2 3
  24. Timmer, John (9 October 2008). "In the deep, a community of one". Ars Technica. Retrieved 1 June 2015.
  25. "NASA Astrobiology". astrobiology.nasa.gov. Retrieved 29 February 2024.
  26. Manzi, M. (16 June 2014). "3D Seismic Imaging of the Ghost-Carbon Leader Reef of the World's Deepest Gold Mine - Mponeng Gold Mine, South Africa". EAGE. Proceedings 76th EAGE Conference and Exhibition Workshops. European Association of Geoscientists & Engineers: cp. doi:10.3997/2214-4609.20140511. ISBN   978-90-73834-90-3 via EarthDoc.
  27. 1 2 3 4 5 6 7 Jolley, S. J.; Freeman, S. R.; Barnicoat, A. C.; Phillips, G. M.; Knipe, R. J.; Pather, A.; Fox, N. P. C.; Strydom, D.; Birch, M. T. G.; Henderson, I. H. C.; Rowland, T. W. (1 June 2004). "Structural controls on Witwatersrand gold mineralisation". Journal of Structural Geology. 26 (6): 1067–1086. Bibcode:2004JSG....26.1067J. doi:10.1016/j.jsg.2003.11.011. ISSN   0191-8141.
  28. 1 2 Cairncross, Bruce (4 July 2021). "The Witwatersrand Goldfield, South Africa". Rocks & Minerals. 96 (4): 296–351. Bibcode:2021RoMin..96..296C. doi:10.1080/00357529.2021.1901207. ISSN   0035-7529.
  29. 1 2 3 Jolley, S. J.; Freeman, S. R.; Barnicoat, A. C.; Phillips, G. M.; Knipe, R. J.; Pather, A.; Fox, N. P. C.; Strydom, D.; Birch, M. T. G.; Henderson, I. H. C.; Rowland, T. W. (1 June 2004). "Structural controls on Witwatersrand gold mineralisation". Journal of Structural Geology. 26 (6): 1067–1086. Bibcode:2004JSG....26.1067J. doi:10.1016/j.jsg.2003.11.011. ISSN   0191-8141.
  30. Jolley, S.J; Henderson, I.H.C; Barnicoat, A.C; Fox, N.P.C (1999). "Thrust-fracture network and hydrothermal gold mineralization: Witwatersrand Basin, South Africa". Geological Society, London, Special Publications. 155: 153–165. doi:10.1144/GSL.SP.1999.155.01.12.
  31. Large, R.R; Meffre, S; Burnett, R; Guy, B; Bull, S; Gilbert, S; Goemann, K; Leonid, D (2013). "Evidence for an Intrabasinal Source and Multiple Concentration Processes in the Formation of the Carbon Leader Reef, Witwatersrand Supergroup, South Africa". Economic Geology. 108 (6): 1215–1241. doi:10.2113/econgeo.108.6.1215.
  32. Möncks, Tycho (9 February 2023). "An Untapped Goldmine: Opportunities for South African Mining". BCG Global. Retrieved 9 April 2024.
  33. 1 2 3 4 5 6 7 8 9 10 Laker, Michiel C. (June 2023). "Environmental Impacts of Gold Mining—With Special Reference to South Africa". Mining. 3 (2): 205–220. doi: 10.3390/mining3020012 . ISSN   2673-6489.
  34. Praveen (11 June 2019). "The top ten deepest mines in the world". Mining Technology. Retrieved 17 February 2024.
  35. 1 2 3 4 Mpanza, Mbalenhle; Adam, Elhadi; Moolla, Raeesa (January 2020). "Dust Deposition Impacts at a Liquidated Gold Mine Village: Gauteng Province in South Africa". International Journal of Environmental Research and Public Health. 17 (14): 4929. doi: 10.3390/ijerph17144929 . ISSN   1660-4601. PMC   7400412 . PMID   32650563.
  36. Maseki, J. (2017). "Health risk posed by enriched heavy metals (As, Cd, and Cr) in airborne particles from Witwatersrand gold tailings". Journal of the Southern African Institute of Mining and Metallurgy. 117 (7): 663–669. doi:10.17159/2411-9717/2017/v117n7a8.
  37. Merget, R.; Bauer, T.; Küpper, H.; Philippou, S.; Bauer, H.; Breitstadt, R.; Bruening, T. (1 January 2002). "Health hazards due to the inhalation of amorphous silica". Archives of Toxicology. 75 (11): 625–634. doi:10.1007/s002040100266. ISSN   1432-0738. PMID   11876495.
  38. Rösner, T.; van Schalkwyk, A. (1 October 2000). "The environmental impact of gold mine tailings footprints in the Johannesburg region, South Africa". Bulletin of Engineering Geology and the Environment. 59 (2): 137–148. doi:10.1007/s100640000037. ISSN   1435-9537.
  39. 1 2 3 Li, T.; Cai, M.F.; Cai, M. (December 2007). "A review of mining-induced seismicity in China". International Journal of Rock Mechanics and Mining Sciences. 44 (8): 1149–1171. Bibcode:2007IJRMM..44.1149L. doi:10.1016/j.ijrmms.2007.06.002. ISSN   1365-1609.
  40. 1 2 3 4 Richardson, Eliza; Jordan, Thomas H. (2002). "Seismicity in Deep Gold Mines of South Africa: Implications for Tectonic Earthquakes". Bulletin of the Seismological Society of America. 92 (5): 1766–1782. Bibcode:2002BuSSA..92.1766R. doi:10.1785/0120000226.
  41. Reporter, Creamer Media. "Three killed in fall of ground at AngloGold's Mponeng". Mining Weekly. Retrieved 12 March 2024.
  42. US Department of Commerce, National Oceanic and Atmospheric Administration. "How does pressure change with ocean depth?". oceanservice.noaa.gov. Retrieved 8 March 2024.
  43. Ziegler, Moritz; Reiter, Karsten; Heidbach, Oliver; Zang, Arno; Kwiatek, Grzegorz; Stromeyer, Dietrich; Dahm, Torsten; Dresen, Georg; Hofmann, Gerhard (1 October 2015). "Mining-Induced Stress Transfer and Its Relation to a M1.9 Seismic Event in an Ultra-deep South African Gold Mine". Pure and Applied Geophysics. 172 (10): 2557–2570. doi:10.1007/s00024-015-1033-x. ISSN   1420-9136. S2CID   199492287.
  44. Kozłowska, Maria; Orlecka-Sikora, Beata; Kwiatek, Grzegorz; Boettcher, Margaret S.; Dresen, Georg (19 December 2014). "Nanoseismicity and picoseismicity rate changes from static stress triggering caused by a M w 2.2 earthquake in Mponeng gold mine, South Africa". Journal of Geophysical Research: Solid Earth. 120 (1): 290–307. doi:10.1002/2014JB011410. ISSN   2169-9313 via AGU.
  45. Kwiatek, G.; Plenkers, K.; Nakatani, Y.; Yabe, Y.; Dresen, G. (2010). "Frequency-Magnitude Characteristics Down to Magnitude -4.4 for Induced Seismicity Recorded at Mponeng Gold Mine, South Africa". Bulletin of the Seismological Society of America. 100 (3): 1165–1173. Bibcode:2010BuSSA.100.1165K. doi:10.1785/0120090277 via GeoScienceWorld.
  46. Riemer, K. L.; Durrheim, R. J. (25 September 2012). "Mining seismicity in the Witwatersrand Basin: monitoring, mechanisms and mitigation strategies in perspective". Journal of Rock Mechanics and Geotechnical Engineering. 4 (3): 228–249. Bibcode:2012JRMGE...4..228R. doi: 10.3724/SP.J.1235.2012.00228 . ISSN   1674-7755.
  47. 1 2 3 4 Plenkers, K.; Kwiatek, G.; Nakatani, M.; Dresen, G. (1 May 2010). "Observation of Seismic Events with Frequencies f > 25 kHz at Mponeng Deep Gold Mine, South Africa". Seismological Research Letters. 81 (3): 467–479. Bibcode:2010SeiRL..81..467P. doi:10.1785/gssrl.81.3.467. ISSN   0895-0695.
  48. Li, T.; Cai, M. F.; Cai, M. (1 December 2007). "A review of mining-induced seismicity in China". International Journal of Rock Mechanics and Mining Sciences. 44 (8): 1149–1171. Bibcode:2007IJRMM..44.1149L. doi:10.1016/j.ijrmms.2007.06.002. ISSN   1365-1609.
  49. 1 2 3 Kwiatek, G; Plenkers, K; Nakatani, M; Yabe, Y; Dressen, G; JAGUARS-Group (2010). "Frequency-Magnitude Characteristics Down to Magnitude -4.4 for Induced Seismicity Recorded at Mponeng Gold Mine, South Africa". Bulletin of the Seismological Society of America. 100 (3): 1165–1173. Bibcode:2010BuSSA.100.1165K. doi:10.1785/0120090277 via GeoScienceWorld.
  50. 1 2 Kwiatek, G; Plenkers, K; Drensen, G; JAGUARS Research Group (2011). "Source Parameters of Picoseismicity Recorded at Mponeng Deep Gold Mine, South Africa: Implications for Scaling Relations". Bulletin of the Seismological Society of America. 101 (6): 2592–2608. Bibcode:2011BuSSA.101.2592K. doi:10.1785/0120110094 via GeoScienceWorld.
  51. "JAGUARS – induced.pl". www.induced.pl. Retrieved 8 March 2024.
  52. South Africa's Mponeng Gold Mine, Build It Bigger, Danny Forster, 13 May 2010, retrieved 8 March 2024{{citation}}: CS1 maint: others (link)
  53. García, Sergio (23 September 2017). "Ecuadorian sets record in run 4,000m below surface". Anadolu Agency.
  54. "This Endurance Athlete Finished Three of the Most Challenging Races on Earth". Men's Health. 5 September 2019. Retrieved 8 March 2024.
  55. Garland, Oliver Lee (1 June 2018), From Core to Sun (Documentary), Levector, Levector, retrieved 8 March 2024