Mponeng Gold Mine: Difference between revisions

Mponeng
	Above-ground operations at Mponeng mine.
Location
	Mponeng Location in South Africa
Province	Gauteng
Country	South Africa
Coordinates	26°26′10″S 27°25′50″E / 26.43611°S 27.43056°E
Owner
Company	Harmony Gold
Website	https://www.harmony.co.za

Browse history interactively

← Previous edit

Content deleted Content added

VisualWikitext

Inline

Latest revision as of 19:36, 15 December 2024

Mponeng is an ultra-deep tabular gold mine in South Africa in the Witwatersrand Basin of the Gauteng Province.^[1] Previously known as Western Deep Levels No1 Shaft, the mine began operations in 1986.^[2] It is one of the most substantial gold mines in the 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. An Ecuadorian marathon runner completed a half marathon within the mine in 2017.^[3]^[7] The mine supports a very large number of people, companies and industries, including entire towns and cities.^[8]

Operations

History

As part of the Witwatersrand, the largest gold mineralization on earth, Mponeng is the result of the discovery of the basin by Europeans. 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]^[2] 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]

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 possibility to run for 43 years.^[11] 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. ^[11] The mine has not been 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.^[11] Like many other operations, Mponeng closed due to the COVID-19 pandemic in May 2020, but has since returned to production.^[11]^[12]

Striking in South Africa's mining district was apparent in the 1900s, for example the South African gold mine strike in August 1946.^[13] 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. In 2012, while AngloGold Ashanti was Mponeng's owner, strikes occurred.^[14] The strikes were a combined result of gold and platinum industry-worker issues in South Africa.^[14] AngloGold's position on the matter was to maintain safety, peace, and stability.^[14] The striking action of 2012 totaled nearly 16% of the total mining workforce of South Africa, not just Mponeng.^[15] AngloGold specifically experienced nearly 35,000 workers putting down their tools in the illegal strike.^[16] 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.^[15]

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.^[17] 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.^[18] Gold is currently worth roughly US$2080/oz (US$1900/Troy oz).^[19] Over 5,400 metric tons of rock are excavated from Mponeng each day.^[20] Harmony Gold, aside from closures, has kept up operations:

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

Produced: 7,449 kg (239,490 oz) of gold^[2]^{[better source needed]}
Grade: 8.43g/t^[2]
Volume of ore milled: 884,000 tons^[2]

Physical conditions

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).^[21] A mixture of concrete, water, and rock is packed into excavated areas, which further acts as an insulator.^[21] Tunnel walls are secured by flexible shotcrete reinforced with steel fibers, which is further held in place by diamond-mesh netting.^[21]

In 2008, researchers looking for extremophile organisms discovered the bacterium Desulforudis audaxviator present within groundwater samples from kilometers deep in the mine.^[22] The name 'Audaxviator' comes from a Latin-language passage in the novel Journey to the Centre of the Earth by Jules Verne: "Descende, audax viator, et terrestre centrum attinges." ("Descend, bold traveller, and attain the centre of the Earth.")^[23]

Geology and gold bearing fractures

The mine sits in the Witwatersrand Basin and utilizes 2 horizons: Ventersdorp Contact Reef and Carbon Leader Reef.^[24] In the Mponeng mine the Ventersdorp Contact Reef is mainly interbedded quartzite and coarse conglomerates and constitutes only a meter or two of thickness.^[25] The Witwatersrand Basin has experienced many surges of thrusting in the past, resulting in abundant fractures.^[25] These small faults often correspond to depositional and sediment contacts.^[25] It is along these faults that mineralizing fluids flow, which lead to the precipitation or mineralisation of gold.^[26] 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.^[25] Mponeng has a proven gold reserve of roughly 46 million ounces (over 1300 tons), more than 8x the second deepest gold mine 'Driefontein', also located in South Africa.^[26]

The gold mineralization is likely related to hydrothermal activity, and occurs in varying lithology of conglomerates, known as the reefs stated above.^[25] The stratigraphy that the gold is found in ranges in thickness, from around 10 cm to a 1-meter.^[27] Gold is found in these variable thickness layers of pebble lags, stacked fluvial deposits, and other stratigraphy.^[27]^[25] Mponeng specifically, gold is associated with previously mentioned thrust fracturing and with the following mineralisations:

Steep quartz/sulphide-bearing fractures
Sub-horizontal quartz fractures
Sulphide-bearing fractures
Ultracataclastics
Mesophased hydrocarbons^[25]

As with most mines, Mponeng is limited to the structural control of the geology. The VCR mineralisation is governed by thrust-fracture systems discussed above, largely from the Lower Kliprivierberg age.^[27] The VCR and CLR themselves are around 2.7 billion years old, and have experienced lots of deformation and change.^[28]^[29]

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.^[30] In 1998, mining industry contributed nearly 90% of the 533.6 million tons of waste that was produced annually.^[31] 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.^[31]

Mining creates two main kinds of waste: waste rock piles and tailing storage facilities (TSFs).^[31] 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.^[32] 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.^[31] Long-term consequences are also of concern, whether the mine activities continue, halt, or a mine is abandoned, these TSFs can pose serious risk the surrounding environment.^[31] Pollution has been found to persist even after 72 years of mine abandonment.^[31]

Beyond the environment, the citizens of the Witwatersrand Basin have been complaining of windblown dust, most of which originates from partially rehabilitated TSFs. ^[33] Anglo Ashanti began recording meteorological data in 2012 and Harmony Gold has since taken over monitoring after the acquisition in 2020.^[33] 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).^[34]^[35] A study in 2020 found elevated value of silica and uranium in PM10 airborne pollution from TSFs of gold mines in the area.^[33]

In South Africa, heavy metal pollution from mining industry is the leading cause of soil and water pollution.^[31] The pollution stems from a few sources:^[31]^[33]

Acid mine drainage (AMD)
Salinization
Elevated levels of potentially toxic elements (PTE)
- Mainly heavy metals, also including arsenic (metalloid).
Airborne dust

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. ^[31]

Immobilizing the PTEs in the TSFs is a main focus of pollution prevention and control.^[31]

Liming the acidic tailings to a suitable pH (>5.5) can significantly reduce the mobility of cationic PTEs. This requires large amount of lime.
Application of clays or organic matter with high cation capacity, with goal of PTE absorption.
Application of sesquioxides (M₂O₃) which would immobilize oxy-anionic PTEs.
Application of hydroxides or phosphates, similar effect of liming.

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.^[36]

Seismicity

Seismicity in mines is common as removing mass amounts of rock can change stress dynamics, especially if pre-existing faults exist.^[37] This seismicity is termed 'mining-induced seismicity', caused by the release of elastic strain but are often low moment magnitude.^[37]^[38] 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.^[37]^[38]

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.^[39] In deep mines, vertical stress can reach 80-100 MPa, equivalent to roughly 10 km under water.^[40]^[41]^[42]^[43] Seismicity in deep gold mines is common, and is often induced by mining activities.^[38]^[44] Two events can be considered:^[38]

Type A - low moment magnitude (<1), clustered in time and space, within 100m of mining surface.
- Induced by blasting, perturbation of excavating processes, closure of stopes.
Type B - possible higher moment magnitude (>3), not clustered in time or space.
- associated with friction dominated existing shear, tectonic earthquakes.

Most earthquakes at depth are mining related (Type A), typically associated with the beginning of a new stope.^[45]

Research

One way to move forward is a better understanding of rock burst and excavation methods. A better understanding can provide better safety protocols.^[46] A prominent use of deep mines and their associated, often low magnitude, earthquakes is to connect laboratory scale experiments to real world situations.^[47]^[48] There is also considerable research trying to understand nucleation of said earthquakes,^[47] and whether they work the same as larger earthquakes.^[48] In Mponeng, JAGUARS (Japanese-German Acoustic Emissions Research in South Africa)^[49] has emplaced a network of accelerometers and piezoelectric acoustic emissions sensors.^[47] 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).^[45] In a one year period, 2007-2008, nearly 500,000 events were recorded, most of which with low (sub 25 kHz) frequencies.^[45] The JAGUARS network is placed below the Ventersdorp Contact Reef, there are eight Acoustic Emissions sensors, two strainmeters, and one triaxial accelerometer that make up the network.^[45]

References

^ 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.
^ ^a ^b ^c ^d ^e "Mponeng Overview". www.harmony.co.za. Retrieved 12 March 2024.
^ ^a ^b 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.
^ "Mponeng Gold Mine, Gauteng". Mining Technology. Retrieved 17 February 2024.
^ Praveen (11 June 2019). "The top ten deepest mines in the world". Mining Technology. Retrieved 17 February 2024.
^ 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.
^ Garcia, Sergio (23 September 2017). "Ecuadorian sets record in run 4,000m below surface". www.aa.com.tr. Retrieved 17 February 2024.
^ Vegter, Ivo (2019). "Why Mining Still Matters" (PDF). South Africa Institute of Race Relations.
^ 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.
^ ^a ^b Barradas, Sheila. "Mponeng mine, South Africa". Mining Weekly. Retrieved 12 March 2024.
^ ^a ^b ^c ^d "Mponeng Gold Mine, South Africa - The World's Deepest Mine". Retrieved 12 March 2024.
^ Bongaerts, Dion; Mazzola, Francesco; Wagner, Wolf (14 May 2021). "Closed for business: The mortality impact of business closures during the Covid-19 madness". PLOS ONE. 16 (5): e0251373. Bibcode:2021PLoSO..1651373B. doi:10.1371/journal.pone.0251373. ISSN 1932-6203. PMC 8121299. PMID 33989322.
^ 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.
^ ^a ^b ^c McKay, David. "Strikes shut down 40% of SA gold". Business. Retrieved 24 March 2024.
^ ^a ^b Muhumuza, Rodney (4 October 2012). "Striking SAfrican miners find strength in numbers". CNBC. Retrieved 24 March 2024.
^ Smith, David (26 September 2012). "South African's goldmines beset by simmering resentment". The Guardian. ISSN 0261-3077. Retrieved 24 March 2024.
^ "Mponeng Gold Mine, South Africa - The World's Deepest Mine". Retrieved 12 March 2024.
^ 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.
^ "Gold Statistics and Information | U.S. Geological Survey". www.usgs.gov. Retrieved 16 February 2024.
^ 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.
^ ^a ^b ^c Wadhams, Nick (March 2011), "Gold Standards: How miners dig for riches in a 2-mile-deep furnace", Wired, vol. 19, no. 3, p. 42.
^ Timmer, John (9 October 2008). "In the deep, a community of one". Ars Technica. Retrieved 1 June 2015.
^ Brahic, Catherine. "Goldmine bug DNA may be key to alien life". New Scientist. Retrieved 16 May 2024.
^ 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.
^ ^a ^b ^c ^d ^e ^f ^g 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.
^ ^a ^b 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.
^ ^a ^b ^c 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.
^ 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 (1): 153–165. Bibcode:1999GSLSP.155..153J. doi:10.1144/GSL.SP.1999.155.01.12.
^ 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. Bibcode:2013EcGeo.108.1215L. doi:10.2113/econgeo.108.6.1215.
^ Möncks, Tycho (9 February 2023). "An Untapped Goldmine: Opportunities for South African Mining". BCG Global. Retrieved 9 April 2024.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j 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.
^ Praveen (11 June 2019). "The top ten deepest mines in the world". Mining Technology. Retrieved 17 February 2024.
^ ^a ^b ^c ^d 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.
^ 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.
^ 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.
^ 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. Bibcode:2000BuEGE..59..137R. doi:10.1007/s100640000037. ISSN 1435-9537.
^ ^a ^b ^c 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.
^ ^a ^b ^c ^d 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.
^ Reporter, Creamer Media. "Three killed in fall of ground at AngloGold's Mponeng". Mining Weekly. Retrieved 12 March 2024.
^ US Department of Commerce, National Oceanic and Atmospheric Administration. "How does pressure change with ocean depth?". oceanservice.noaa.gov. Retrieved 8 March 2024.
^ 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.
^ 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.
^ 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.
^ 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.
^ ^a ^b ^c ^d 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.
^ 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.
^ ^a ^b ^c 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.
^ ^a ^b 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.
^ "JAGUARS – induced.pl". www.induced.pl. Retrieved 8 March 2024.

[:32-1] 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.

[HarmonyOverview-2] "Mponeng Overview". www.harmony.co.za. Retrieved 12 March 2024.

[:4-3] 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.

[:20-4] "Mponeng Gold Mine, Gauteng". Mining Technology. Retrieved 17 February 2024.

[:17-5] Praveen (11 June 2019). "The top ten deepest mines in the world". Mining Technology. Retrieved 17 February 2024.

[:52-6] 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.

[:22-7] Garcia, Sergio (23 September 2017). "Ecuadorian sets record in run 4,000m below surface". www.aa.com.tr. Retrieved 17 February 2024.

[:21-8] Vegter, Ivo (2019). "Why Mining Still Matters" (PDF). South Africa Institute of Race Relations.

[:13-9] 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.

[Barradas_2016-10] Barradas, Sheila. "Mponeng mine, South Africa". Mining Weekly. Retrieved 12 March 2024.

[:123-11] "Mponeng Gold Mine, South Africa - The World's Deepest Mine". Retrieved 12 March 2024.

[12] Bongaerts, Dion; Mazzola, Francesco; Wagner, Wolf (14 May 2021). "Closed for business: The mortality impact of business closures during the Covid-19 madness". PLOS ONE. 16 (5): e0251373. Bibcode:2021PLoSO..1651373B. doi:10.1371/journal.pone.0251373. ISSN 1932-6203. PMC 8121299. PMID 33989322.

[13] 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.

[:15-14] McKay, David. "Strikes shut down 40% of SA gold". Business. Retrieved 24 March 2024.

[Muhumuza2012-15] Muhumuza, Rodney (4 October 2012). "Striking SAfrican miners find strength in numbers". CNBC. Retrieved 24 March 2024.

[16] Smith, David (26 September 2012). "South African's goldmines beset by simmering resentment". The Guardian. ISSN 0261-3077. Retrieved 24 March 2024.

[:122-17] "Mponeng Gold Mine, South Africa - The World's Deepest Mine". Retrieved 12 March 2024.

[18] 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.

[19] "Gold Statistics and Information | U.S. Geological Survey". www.usgs.gov. Retrieved 16 February 2024.

[:42-20] 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.

[Wired-21] Wadhams, Nick (March 2011), "Gold Standards: How miners dig for riches in a 2-mile-deep furnace", Wired, vol. 19, no. 3, p. 42.

[22] Timmer, John (9 October 2008). "In the deep, a community of one". Ars Technica. Retrieved 1 June 2015.

[23] Brahic, Catherine. "Goldmine bug DNA may be key to alien life". New Scientist. Retrieved 16 May 2024.

[:5-24] 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.

[:02-25] ^ ^a ^b ^c ^d ^e ^f ^g 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.

[:133-26] 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.

[:04-27] 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] 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 (1): 153–165. Bibcode:1999GSLSP.155..153J. doi:10.1144/GSL.SP.1999.155.01.12.

[29] 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. Bibcode:2013EcGeo.108.1215L. doi:10.2113/econgeo.108.6.1215.

[30] Möncks, Tycho (9 February 2023). "An Untapped Goldmine: Opportunities for South African Mining". BCG Global. Retrieved 9 April 2024.

[:18-31] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j 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.

[:172-32] Praveen (11 June 2019). "The top ten deepest mines in the world". Mining Technology. Retrieved 17 February 2024.

[:19-33] 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.

[34] 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.

[35] 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.

[36] 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. Bibcode:2000BuEGE..59..137R. doi:10.1007/s100640000037. ISSN 1435-9537.

[:9-37] 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.

[:12-38] 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.

[39] Reporter, Creamer Media. "Three killed in fall of ground at AngloGold's Mponeng". Mining Weekly. Retrieved 12 March 2024.

[40] US Department of Commerce, National Oceanic and Atmospheric Administration. "How does pressure change with ocean depth?". oceanservice.noaa.gov. Retrieved 8 March 2024.

[:3-41] 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.

[42] 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.

[43] 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.

[:2-44] 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.

[:102-45] 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.

[46] 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.

[:72-47] 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.

[:82-48] 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.

[49] "JAGUARS – induced.pl". www.induced.pl. Retrieved 8 March 2024.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]

[13]

[14]

[15]

[16]

[17]

[18]

[19]

[20]

[21]

[22]

[23]

[24]

[25]

[26]

[27]

[28]

[29]

[30]

[31]

[32]

[33]

[34]

[35]

[36]

[37]

[38]

[39]

[40]

[41]

[42]

[43]

[44]

[45]

[46]

[47]

[48]

[49]

@@ Line 1: / Line 1: @@
-{{short description|4 km deep gold mine in Gauteng province near Johannesburg, South Africa. World's Deepest Mine.}}
+{{short description|10 km deep gold mine in Gauteng province near Johannesburg, South Africa. World's Deepest Mine.}}
 {{Infobox gold mine
 | name = Mponeng
@@ Line 23: / Line 23: @@
 }}{{Use dmy dates|date=April 2022}}
-'''Mponeng''' is a [[Gold mining|gold mine]] in [[South Africa]]'s [[Gauteng|Gauteng Province]],  specifically it is an ultra-deep tabular mine of the [[Witwatersrand]] Basin. <ref name=":32">{{Cite journal |last1=Ziegler |first1=Moritz |last2=Reiter |first2=Karsten |last3=Heidbach |first3=Oliver |last4=Zang |first4=Arno |last5=Kwiatek |first5=Grzegorz |last6=Stromeyer |first6=Dietrich |last7=Dahm |first7=Torsten |last8=Dresen |first8=Georg |last9=Hofmann |first9=Gerhard |date=2015-10-01 |title=Mining-Induced Stress Transfer and Its Relation to a M1.9 Seismic Event in an Ultra-deep South African Gold Mine |url=https://doi.org/10.1007/s00024-015-1033-x |journal=Pure and Applied Geophysics |language=en |volume=172 |issue=10 |pages=2557–2570 |doi=10.1007/s00024-015-1033-x |issn=1420-9136}}</ref>  Previously know as Western Deep Levels No1 Shaft, the mine began operations in [[1986]]. <ref name=":112">{{Cite web |url=https://www.harmony.co.za/operations/south-africa/underground/mponeng/#:~:text=The%20mine,%20which%20began%20producing,and%203%20740m%20below%20surface. |access-date=2024-03-12 |website=www.harmony.co.za}}</ref>  Considered to be one of the most substantial gold mine mines in world in production and magnitude,  reaching over 4km (2.5 mi) below the surface. <ref name=":4">{{Cite web |last=Wadhams |first=Nick |date=11 March 2011 |title=Gold Standards: How miners dig for riches in a 2-mile-deep furnace |url=https://www.wired.com/2011/02/st-ultradeepmines/ |publisher=Wired |page=42 |edition=Vol. 19 No. 3}}</ref><ref name=":20">{{Cite web |title=Mponeng Gold Mine, Gauteng |url=https://www.mining-technology.com/projects/mponeng/ |access-date=2024-02-17 |website=Mining Technology |language=en-US}}</ref>  At this depth Mponeng takes the title of worlds deepest mine from ground level,  with aims to deepen the mine beyond 4km in order to reach more reserves. <ref name=":17">{{Cite web |last=Praveen |date=2019-06-11 |title=The top ten deepest mines in the world |url=https://www.mining-technology.com/features/feature-top-ten-deepest-mines-world-south-africa/ |access-date=2024-02-17 |website=Mining Technology |language=en-US}}</ref><ref name=":52">{{Cite journal |last=Manzi |first=M. |date=2014-06-16 |title=3D Seismic Imaging of the Ghost-Carbon Leader Reef of the World's Deepest Gold Mine - Mponeng Gold Mine, South Africa |url=https://www.earthdoc.org/content/papers/10.3997/2214-4609.20140511 |journal=EAGE |series=Proceedings 76th EAGE Conference and Exhibition Workshops |language=en |publisher=European Association of Geoscientists & Engineers |pages=cp |doi=10.3997/2214-4609.20140511 |isbn=978-90-73834-90-3 |via=EarthDoc}}</ref> A trip from the surface to it's depth takes over an hour,  but the harsh conditions of the mine did not stop an [[Ecuadorians|Ecuadorian]] marathon runner from completing a [[half marathon]] within the mine. <ref name=":4" /><ref name=":22">{{Cite web |last=Garcia |first=Sergio |date=23 September 2017 |title=Ecuadorian sets record in run 4,000m below surface |url=https://www.aa.com.tr/en/americas/ecuadorian-sets-record-in-run-4-000m-below-surface/917320 |access-date=2024-02-17 |website=www.aa.com.tr}}</ref> Mponeng comes with economic, environmental, societal, and seismic relations but mining in South Africa has had a huge effect on the technologies of deep gold mining around the world, South Africa is even considered a pioneer of the trade.<ref name=":21">{{Cite journal |last=Vegter |first=Ivo |date=2018 |title=Why Mining Still Matters |journal=South Africa Institute of Race Relations |volume=11}}</ref>
+'''Mponeng''' is an ultra-deep tabular [[Gold mining in South Africa|gold mine in South Africa]] in the [[Witwatersrand]] Basin of the [[Gauteng|Gauteng Province]].<ref name=":32">{{Cite journal |last1=Ziegler |first1=Moritz |last2=Reiter |first2=Karsten |last3=Heidbach |first3=Oliver |last4=Zang |first4=Arno |last5=Kwiatek |first5=Grzegorz |last6=Stromeyer |first6=Dietrich |last7=Dahm |first7=Torsten |last8=Dresen |first8=Georg |last9=Hofmann |first9=Gerhard |date=2015-10-01 |title=Mining-Induced Stress Transfer and Its Relation to a M1.9 Seismic Event in an Ultra-deep South African Gold Mine |url=https://doi.org/10.1007/s00024-015-1033-x |journal=Pure and Applied Geophysics |language=en |volume=172 |issue=10 |pages=2557–2570 |doi=10.1007/s00024-015-1033-x |issn=1420-9136}}</ref> Previously known as Western Deep Levels No1 Shaft, the mine began operations in [[1986]].<ref name="HarmonyOverview"/> It is one of the most substantial gold mines in the world in terms of production and magnitude, reaching over {{Convert|4|km|mi}} below the surface.<ref name=":4">{{Cite web |last=Wadhams |first=Nick |date=11 March 2011 |title=Gold Standards: How miners dig for riches in a 2-mile-deep furnace |url=https://www.wired.com/2011/02/st-ultradeepmines/ |publisher=Wired |page=42 |edition=Vol. 19 No. 3}}</ref><ref name=":20">{{Cite web |title=Mponeng Gold Mine, Gauteng |url=https://www.mining-technology.com/projects/mponeng/ |access-date=2024-02-17 |website=Mining Technology |language=en-US}}</ref> 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.<ref name=":17">{{Cite web |last=Praveen |date=2019-06-11 |title=The top ten deepest mines in the world |url=https://www.mining-technology.com/features/feature-top-ten-deepest-mines-world-south-africa/ |access-date=2024-02-17 |website=Mining Technology |language=en-US}}</ref><ref name=":52">{{Cite journal |last=Manzi |first=M. |date=2014-06-16 |title=3D Seismic Imaging of the Ghost-Carbon Leader Reef of the World's Deepest Gold Mine - Mponeng Gold Mine, South Africa |url=https://www.earthdoc.org/content/papers/10.3997/2214-4609.20140511 |journal=EAGE |series=Proceedings 76th EAGE Conference and Exhibition Workshops |language=en |publisher=European Association of Geoscientists & Engineers |pages=cp |doi=10.3997/2214-4609.20140511 |isbn=978-90-73834-90-3 |via=EarthDoc}}</ref> A trip from the surface to its deepest point takes over an hour. An [[Ecuadorians|Ecuadorian]] marathon runner completed a [[half marathon]] within the mine in 2017.<ref name=":4" /><ref name=":22">{{Cite web |last=Garcia |first=Sergio |date=23 September 2017 |title=Ecuadorian sets record in run 4,000m below surface |url=https://www.aa.com.tr/en/americas/ecuadorian-sets-record-in-run-4-000m-below-surface/917320 |access-date=2024-02-17 |website=www.aa.com.tr}}</ref> The mine supports a very large number of people, companies and industries, including entire towns and cities.<ref name=":21">{{Cite journal |last=Vegter |first=Ivo |date=2019 |title=Why Mining Still Matters |journal=South Africa Institute of Race Relations |url=https://irr.org.za/reports/occasional-reports/files/01-2014-page-1-21-2014-why-mining-still-matters-11-03-2019.pdf}}</ref>
-== Operations, History, and Ownership ==
+== Operations ==
-=== Operations and Ownership ===
+=== History ===
+As part of the Witwatersrand, the largest gold mineralization on earth, Mponeng is the result of the discovery of the basin by Europeans. 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.<ref name=":13">{{Cite journal |last=Cairncross |first=Bruce |date=2021-07-04 |title=The Witwatersrand Goldfield, South Africa |url=https://www.tandfonline.com/doi/full/10.1080/00357529.2021.1901207 |journal=Rocks & Minerals |language=en |volume=96 |issue=4 |pages=296–351 |bibcode=2021RoMin..96..296C |doi=10.1080/00357529.2021.1901207 |issn=0035-7529}}</ref> These discoveries led to many mining operations and after shaft sinking for about 5 years (1981) Mponeng officially began mining operations in 1986.<ref name="Barradas 2016">{{Cite web |last=Barradas |first=Sheila |title=Mponeng mine, South Africa |url=https://www.miningweekly.com/article/mponeng-mine-south-africa-2016-07-08 |access-date=2024-03-12 |website=Mining Weekly |language=en}}</ref><ref name="HarmonyOverview">{{Cite web |url=https://www.harmony.co.za/operations/south-africa/underground/mponeng/|access-date=2024-03-12 |website=www.harmony.co.za |title=Mponeng Overview }}</ref> 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.<ref name="Barradas 2016" />
-[[Harmony Gold (mining)|Harmony Gold]], Africa's largest gold producer, purchased Mponeng from [[AngloGold Ashanti]] (AGA) in 2020, Harmony paid approximately $200 million. Harmony Gold also acquired Mine Waste Solutions as they gathered the remainder of AGA's assets in late 2020.'''<ref name=":122">{{Cite web |title=Mponeng Gold Mine, South Africa - The World's Deepest Mine |url=https://www.nsenergybusiness.com/projects/mponeng-gold-mine/ |access-date=2024-03-12 |language=en-US}}</ref>''' 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.<ref>{{Cite web |last=Burron |first=Ian |date=2023-04-13 |title=How Low Can you go? The Challenges of Deep Mining {{!}} Geology for Investors |url=https://www.geologyforinvestors.com/how-low-can-you-go-the-challenges-of-deep-mining/ |access-date=2024-02-17 |website=www.geologyforinvestors.com |language=en-US}}</ref> Gold is currently worth roughly US$2080/oz (US$1900/Troy oz).<ref>{{Cite web |title=Gold Statistics and Information {{!}} U.S. Geological Survey |url=https://www.usgs.gov/centers/national-minerals-information-center/gold-statistics-and-information |access-date=2024-02-16 |website=www.usgs.gov}}</ref> Over 5,400 metric tons of rock are excavated from Mponeng each day.<ref name=":42">{{Cite web |last=Wadhams |first=Nick |date=11 March 2011 |title=Gold Standards: How miners dig for riches in a 2-mile-deep furnace |url=https://www.wired.com/2011/02/st-ultradeepmines/ |publisher=Wired |page=42 |edition=Vol. 19 No. 3}}</ref> Harmony Gold, aside from closures, has kept up operations:
+[[File:Liv Shange addresses striking mineworkers in Carletonville during 2012 national strikes.jpg|thumb|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 possibility to run for 43 years.<ref name=":123">{{Cite web |title=Mponeng Gold Mine, South Africa - The World's Deepest Mine |url=https://www.nsenergybusiness.com/projects/mponeng-gold-mine/ |access-date=2024-03-12 |language=en-US}}</ref> 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. <ref name=":123" /> The mine has not been 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.<ref name=":123" /> Like many other operations, Mponeng closed due to the [[COVID-19|COVID-19 pandemic]] in May 2020, but has since returned to production.<ref name=":123" /><ref>{{Cite journal |last1=Bongaerts |first1=Dion |last2=Mazzola |first2=Francesco |last3=Wagner |first3=Wolf |date=2021-05-14 |title=Closed for business: The mortality impact of business closures during the Covid-19 madness |journal=PLOS ONE |language=en |volume=16 |issue=5 |pages=e0251373 |doi=10.1371/journal.pone.0251373 |issn=1932-6203 |pmc=8121299 |pmid=33989322 |doi-access=free|bibcode=2021PLoSO..1651373B }}</ref>
+Striking in South Africa's mining district was apparent in the 1900s, for example the South African gold mine strike in August 1946.<ref>{{Cite journal |last=James |first=Wilmot G. |date=1987 |title=Grounds for a Strike: South African Gold Mining in the 1940s |url=https://www.jstor.org/stable/3601267 |journal=African Economic History |issue=16 |pages=1–22 |doi=10.2307/3601267 |issn=0145-2258 |jstor=3601267}}</ref> 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. In 2012, while AngloGold Ashanti was Mponeng's owner, strikes occurred.<ref name=":15">{{Cite web |last=McKay |first=David |title=Strikes shut down 40% of SA gold |url=https://www.news24.com/fin24/strikes-shut-down-40-of-sa-gold-20120927 |access-date=2024-03-24 |website=Business |language=en-US}}</ref> The strikes were a combined result of gold and platinum industry-worker issues in South Africa.<ref name=":15" /> AngloGold's position on the matter was to maintain safety, peace, and stability.<ref name=":15" /> The striking action of 2012 totaled nearly 16% of the total mining workforce of South Africa, not just Mponeng.<ref name="Muhumuza2012">{{Cite web |first1=Rodney |last1=Muhumuza |date=2012-10-04 |title=Striking SAfrican miners find strength in numbers |url=https://www.cnbc.com/2012/10/04/striking-safrican-miners-find-strength-in-numbers.html |access-date=2024-03-24 |website=CNBC |language=en}}</ref> AngloGold specifically experienced nearly 35,000 workers putting down their tools in the illegal strike.<ref>{{Cite news |last=Smith |first=David |date=2012-09-26 |title=South African's goldmines beset by simmering resentment |url=https://www.theguardian.com/world/2012/sep/26/south-african-goldmines-simmering-resentment |access-date=2024-03-24 |work=The Guardian |language=en-GB |issn=0261-3077}}</ref> Although not at Mponeng, the strike of 2012 included a wildcat strike at a nearby platinum mine ended with [[Marikana massacre|34 miners dying]] from police interactions.<ref name="Muhumuza2012" />
-The most recent publication from Harmony Gold outlines their 2023 year production:
+=== Operations and ownership ===
-* Produced: 7,449&nbsp;kg (239,490 oz) of gold<ref name=":6">{{Cite web |title=Mponeng - Operating Performance FY23 |url=https://www.harmony.co.za/operations/south-africa/underground/mponeng/ |access-date=2024-02-29 |website=www.harmony.co.za}}</ref>
+[[Harmony Gold (mining)|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.'''<ref name=":122">{{Cite web |title=Mponeng Gold Mine, South Africa - The World's Deepest Mine |url=https://www.nsenergybusiness.com/projects/mponeng-gold-mine/ |access-date=2024-03-12 |language=en-US}}</ref>''' 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.<ref>{{Cite web |last=Burron |first=Ian |date=2023-04-13 |title=How Low Can you go? The Challenges of Deep Mining {{!}} Geology for Investors |url=https://www.geologyforinvestors.com/how-low-can-you-go-the-challenges-of-deep-mining/ |access-date=2024-02-17 |website=www.geologyforinvestors.com |language=en-US}}</ref> Gold is currently worth roughly US$2080/oz (US$1900/Troy oz).<ref>{{Cite web |title=Gold Statistics and Information {{!}} U.S. Geological Survey |url=https://www.usgs.gov/centers/national-minerals-information-center/gold-statistics-and-information |access-date=2024-02-16 |website=www.usgs.gov}}</ref> Over 5,400 metric tons of rock are excavated from Mponeng each day.<ref name=":42">{{Cite web |last=Wadhams |first=Nick |date=11 March 2011 |title=Gold Standards: How miners dig for riches in a 2-mile-deep furnace |url=https://www.wired.com/2011/02/st-ultradeepmines/ |publisher=Wired |page=42 |edition=Vol. 19 No. 3}}</ref> Harmony Gold, aside from closures, has kept up operations:
-* Grade: 8.43g/t<ref name=":6" />
-* Volume of ore milled: 884,000 tons<ref name=":6" />
+The most recent publication from Harmony Gold outlines their 2023 year production:
-=== History ===
-Being a part of the Witwatersrand, the largest gold deposit on earth, Mponeng is the result of the discovery of the basin.  Beginning in the 1850-70s a series of discoveries were made in the area, Pieter Jacob panning gold from a river and a Henry Lewis finding quartz and gold vein on a farm. <ref name=":13">{{Cite journal |last=Cairncross |first=Bruce |date=2021-07-04 |title=The Witwatersrand Goldfield, South Africa |url=https://www.tandfonline.com/doi/full/10.1080/00357529.2021.1901207 |journal=Rocks & Minerals |language=en |volume=96 |issue=4 |pages=296–351 |doi=10.1080/00357529.2021.1901207 |bibcode=2021RoMin..96..296C |issn=0035-7529}}</ref>  These discoveries led to many mining operations and after shaft sinking for about 5 years (1981) Mponeng officially began mining operations in 1986.<ref name=":142">{{Cite web |last=Barradas |first=Sheila |title=Mponeng mine, South Africa |url=https://www.miningweekly.com/article/mponeng-mine-south-africa-2016-07-08 |access-date=2024-03-12 |website=Mining Weekly |language=en}}</ref> <ref name=":11">{{Cite web |url=https://www.harmony.co.za/operations/south-africa/underground/mponeng/#:~:text=The%20mine,%20which%20began%20producing,and%203%20740m%20below%20surface. |access-date=2024-03-12 |website=www.harmony.co.za}}</ref>Before Mponeng, the mine was known as the Western Deep Levels South Shaft or the No1 Shaft, the name Mponeng came to be in 1999. <ref name=":142" />
-[[File:Liv Shange addresses striking mineworkers in Carletonville during 2012 national strikes.jpg|thumb|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. <ref name=":123">{{Cite web |title=Mponeng Gold Mine, South Africa - The World's Deepest Mine |url=https://www.nsenergybusiness.com/projects/mponeng-gold-mine/ |access-date=2024-03-12 |language=en-US}}</ref> 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. <ref name=":123" /> 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. <ref name=":123" /> Like most businesses, <ref>{{Cite journal |last1=Bongaerts |first1=Dion |last2=Mazzola |first2=Francesco |last3=Wagner |first3=Wolf |date=2021-05-14 |title=Closed for business: The mortality impact of business closures during the Covid-19 pandemic |journal=PLOS ONE |language=en |volume=16 |issue=5 |pages=e0251373 |doi=10.1371/journal.pone.0251373 |doi-access=free |issn=1932-6203 |pmc=8121299 |pmid=33989322}}</ref> Mponeng closed its doors due to [[COVID-19]] in May of 2020, but has since returned the producing. <ref name=":123" />
+* Produced: 7,449&nbsp;kg (239,490 oz) of gold<ref name="HarmonyOverview"/>{{Better source needed|reason=The current source is insufficiently reliable ([[WP:NOTRS]]).|date=April 2024}}
-Striking in South Africa's mining district was apparent in the 1900s, for example the South African gold mine strike in August 1946.<ref>{{Cite journal |last=James |first=Wilmot G. |date=1987 |title=Grounds for a Strike: South African Gold Mining in the 1940s |url=https://www.jstor.org/stable/3601267 |journal=African Economic History |issue=16 |pages=1–22 |doi=10.2307/3601267 |jstor=3601267 |issn=0145-2258}}</ref> 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.<ref name=":15">{{Cite web |last=McKay |first=David |title=Strikes shut down 40% of SA gold |url=https://www.news24.com/fin24/strikes-shut-down-40-of-sa-gold-20120927 |access-date=2024-03-24 |website=Business |language=en-US}}</ref>  The strikes were a combined result of gold and platinum industry-worker issues in South Africa.<ref name=":15" /> AngloGold's position on the matter was to maintain safety, peace, and stability.<ref name=":15" /> The striking action of 2012 totaled nearly 16% of the total mining workforce of South Africa, not just Mponeng.<ref name=":16">{{Cite web |last=Press |first=RODNEY MUHUMUZA, Associated |date=2012-10-04 |title=Striking SAfrican miners find strength in numbers |url=https://www.cnbc.com/2012/10/04/striking-safrican-miners-find-strength-in-numbers.html |access-date=2024-03-24 |website=CNBC |language=en}}</ref> AngloGold specifically experienced nearly 35,000 workers putting down there tools in the illegal strike.<ref>{{Cite news |last=Smith |first=David |date=2012-09-26 |title=South African's goldmines beset by simmering resentment |url=https://www.theguardian.com/world/2012/sep/26/south-african-goldmines-simmering-resentment |access-date=2024-03-24 |work=The Guardian |language=en-GB |issn=0261-3077}}</ref> 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.<ref name=":16" />
+* Grade: 8.43g/t<ref name="HarmonyOverview" />
+* Volume of ore milled: 884,000 tons<ref name="HarmonyOverview" />
 ==Physical conditions==
 [[File:Desulforudis audaxviator.jpg|thumb|A colony of ''Desulforudis audaxviator'', discovered in the Mponeng gold mine.. See article [https://astrobiology.nasa.gov/news/life-without-the-sun/#:~:text=An%20ecosystem%20discovered%202.8%20kilometers,completely%20independently%20of%20the%20Sun. Life without The Sun] for details]]
-The temperature of the rock reaches {{convert|66|°C}}, and the mine pumps [[slurry ice]] underground to cool the tunnel air to below {{convert|30|°C}}.{{r|Wired}} A mixture of [[concrete]], [[water]], and rock is packed into excavated areas, which further acts as an insulator.{{r|Wired}} Tunnel walls are secured by flexible [[shotcrete]] reinforced with steel fibers, which is further held in place by diamond-mesh netting.{{r|Wired}}
+The temperature of the rock reaches {{convert|66|°C}}, and the mine pumps [[slurry ice]] underground to cool the tunnel air to below {{convert|30|°C}}.{{r|Wired}} A mixture of [[concrete]], [[water]], and rock is packed into excavated areas, which further acts as an insulator.{{r|Wired}} Tunnel walls are secured by flexible [[shotcrete]] reinforced with steel fibers, which is further held in place by diamond-mesh netting.<ref name="Wired">{{citation |title=Gold Standards: How miners dig for riches in a 2-mile-deep furnace |magazine=[[Wired (magazine)|Wired]] |last=Wadhams |first=Nick |date=March 2011 |volume=19 |issue=3 |page=42 }}.</ref>
-In 2008, researchers looking for [[extremophile]] organisms discovered the bacterium ''[[Desulforudis audaxviator]]'' present within groundwater samples from kilometers deep in the mine.<ref>{{cite web |url=https://arstechnica.com/science/2008/10/in-the-deep-a-community-of-one/ |title=In the deep, a community of one |last=Timmer |first=John |date=October 9, 2008 |website=Ars Technica |access-date=June 1, 2015}}</ref> The name 'Audaxviator' comes from the popular novel "[[Journey to the Center of the Earth]]" (Jules Verne), which means 'descend, bold traveler, and attain the center of the Earth'.<ref>{{Cite web |title=NASA Astrobiology |url=https://astrobiology.nasa.gov/news/life-without-the-sun/#:~:text=An%20ecosystem%20discovered%202.8%20kilometers,completely%20independently%20of%20the%20Sun. |access-date=2024-02-29 |website=astrobiology.nasa.gov |language=en-EN}}</ref>
+In 2008, researchers looking for [[extremophile]] organisms discovered the bacterium ''[[Desulforudis audaxviator]]'' present within groundwater samples from kilometers deep in the mine.<ref>{{cite web |url=https://arstechnica.com/science/2008/10/in-the-deep-a-community-of-one/ |title=In the deep, a community of one |last=Timmer |first=John |date=October 9, 2008 |website=Ars Technica |access-date=June 1, 2015}}</ref> The name 'Audaxviator' comes from a Latin-language passage in the novel [[Journey to the Center of the Earth|''Journey to the Centre of the Earth'']] by [[Jules Verne]]: {{lang|la|"Descende, audax viator, et terrestre centrum attinges."}} ("Descend, bold traveller, and attain the centre of the Earth.")<ref>{{cite web |last1=Brahic |first1=Catherine |title=Goldmine bug DNA may be key to alien life |url=https://www.newscientist.com/article/dn14906-goldmine-bug-dna-may-be-key-to-alien-life/ |website=New Scientist |access-date=16 May 2024}}</ref>
 == Geology and gold bearing fractures ==
-The mine sits in the Witwatersrand Basin and utilizes 2 horizons; Ventersdorp Contact Reef and Carbon Leader Reef.<ref name=":5">{{Cite journal |last=Manzi |first=M. |date=2014-06-16 |title=3D Seismic Imaging of the Ghost-Carbon Leader Reef of the World's Deepest Gold Mine - Mponeng Gold Mine, South Africa |url=https://www.earthdoc.org/content/papers/10.3997/2214-4609.20140511 |journal=EAGE |series=Proceedings 76th EAGE Conference and Exhibition Workshops |language=en |publisher=European Association of Geoscientists & Engineers |pages=cp |doi=10.3997/2214-4609.20140511 |isbn=978-90-73834-90-3 |via=EarthDoc}}</ref> In the Mponeng mine the Ventersdorp Contact Reef is mainly interbedded [[quartzite]] and coarse conglomerates and constitutes only a meter or two of thickness.<ref name=":02"/> The Witwatersrand Basin has experienced many surges of thrusting in the past, resulting in abundant fractures.<ref name=":02">{{Cite journal |last1=Jolley |first1=S. J. |last2=Freeman |first2=S. R. |last3=Barnicoat |first3=A. C. |last4=Phillips |first4=G. M. |last5=Knipe |first5=R. J. |last6=Pather |first6=A. |last7=Fox |first7=N. P. C. |last8=Strydom |first8=D. |last9=Birch |first9=M. T. G. |last10=Henderson |first10=I. H. C. |last11=Rowland |first11=T. W. |date=2004-06-01 |title=Structural controls on Witwatersrand gold mineralisation |url=https://www.sciencedirect.com/science/article/pii/S0191814103001846 |journal=Journal of Structural Geology |volume=26 |issue=6 |pages=1067–1086 |doi=10.1016/j.jsg.2003.11.011 |bibcode=2004JSG....26.1067J |issn=0191-8141}}</ref> These small faults often correspond to depositional and sediment contacts.<ref name=":02" /> It is along these faults that mineralizing fluids flow, which lead to the precipitation or mineralization of gold.<ref name=":133">{{Cite journal |last=Cairncross |first=Bruce |date=2021-07-04 |title=The Witwatersrand Goldfield, South Africa |url=https://www.tandfonline.com/doi/full/10.1080/00357529.2021.1901207 |journal=Rocks & Minerals |language=en |volume=96 |issue=4 |pages=296–351 |bibcode=2021RoMin..96..296C |doi=10.1080/00357529.2021.1901207 |issn=0035-7529}}</ref> 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.<ref name=":02" /> 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 mine|Driefontein]]' also located in South Africa.<ref name=":133"/>
+The mine sits in the Witwatersrand Basin and utilizes 2 horizons: Ventersdorp Contact Reef and Carbon Leader Reef.<ref name=":5">{{Cite journal |last=Manzi |first=M. |date=2014-06-16 |title=3D Seismic Imaging of the Ghost-Carbon Leader Reef of the World's Deepest Gold Mine - Mponeng Gold Mine, South Africa |url=https://www.earthdoc.org/content/papers/10.3997/2214-4609.20140511 |journal=EAGE |series=Proceedings 76th EAGE Conference and Exhibition Workshops |language=en |publisher=European Association of Geoscientists & Engineers |pages=cp |doi=10.3997/2214-4609.20140511 |isbn=978-90-73834-90-3 |via=EarthDoc}}</ref> In the Mponeng mine the Ventersdorp Contact Reef is mainly interbedded [[quartzite]] and coarse conglomerates and constitutes only a meter or two of thickness.<ref name=":02"/> The Witwatersrand Basin has experienced many surges of thrusting in the past, resulting in abundant fractures.<ref name=":02">{{Cite journal |last1=Jolley |first1=S. J. |last2=Freeman |first2=S. R. |last3=Barnicoat |first3=A. C. |last4=Phillips |first4=G. M. |last5=Knipe |first5=R. J. |last6=Pather |first6=A. |last7=Fox |first7=N. P. C. |last8=Strydom |first8=D. |last9=Birch |first9=M. T. G. |last10=Henderson |first10=I. H. C. |last11=Rowland |first11=T. W. |date=2004-06-01 |title=Structural controls on Witwatersrand gold mineralisation |url=https://www.sciencedirect.com/science/article/pii/S0191814103001846 |journal=Journal of Structural Geology |volume=26 |issue=6 |pages=1067–1086 |doi=10.1016/j.jsg.2003.11.011 |bibcode=2004JSG....26.1067J |issn=0191-8141}}</ref> These small faults often correspond to depositional and sediment contacts.<ref name=":02" /> It is along these faults that mineralizing fluids flow, which lead to the precipitation or mineralisation of gold.<ref name=":133">{{Cite journal |last=Cairncross |first=Bruce |date=2021-07-04 |title=The Witwatersrand Goldfield, South Africa |url=https://www.tandfonline.com/doi/full/10.1080/00357529.2021.1901207 |journal=Rocks & Minerals |language=en |volume=96 |issue=4 |pages=296–351 |bibcode=2021RoMin..96..296C |doi=10.1080/00357529.2021.1901207 |issn=0035-7529}}</ref> 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.<ref name=":02" /> Mponeng has a proven gold reserve of roughly 46 million ounces (over 1300 tons), more than 8x the second deepest gold mine '[[Driefontein mine|Driefontein]]', also located in South Africa.<ref name=":133"/>
-The gold [[Mineralization (geology)|mineralization]] is likely related to hydrothermal activity, and occurs in varying lithology of conglomerates, known as the reefs stated above.<ref name=":02" /> The [[stratigraphy]] that the gold is found in ranges in thickness,  from around 10&nbsp;cm to a 1-meter.<ref name=":04">{{Cite journal |last1=Jolley |first1=S. J. |last2=Freeman |first2=S. R. |last3=Barnicoat |first3=A. C. |last4=Phillips |first4=G. M. |last5=Knipe |first5=R. J. |last6=Pather |first6=A. |last7=Fox |first7=N. P. C. |last8=Strydom |first8=D. |last9=Birch |first9=M. T. G. |last10=Henderson |first10=I. H. C. |last11=Rowland |first11=T. W. |date=2004-06-01 |title=Structural controls on Witwatersrand gold mineralisation |url=https://www.sciencedirect.com/science/article/pii/S0191814103001846 |journal=Journal of Structural Geology |volume=26 |issue=6 |pages=1067–1086 |doi=10.1016/j.jsg.2003.11.011 |bibcode=2004JSG....26.1067J |issn=0191-8141}}</ref> Gold is found in these variable thickness layers of pebble lags, stacked [[Fluvial sediment processes|fluvial]] deposits, and other [[stratigraphy]].<ref name=":04"/><ref name=":02" /> Mponeng specifically,  gold is associated with previously mentioned thrust fracturing and with the following mineralization's:
+The gold [[Mineralization (geology)|mineralization]] is likely related to hydrothermal activity, and occurs in varying lithology of conglomerates, known as the reefs stated above.<ref name=":02" /> The [[stratigraphy]] that the gold is found in ranges in thickness,  from around 10&nbsp;cm to a 1-meter.<ref name=":04">{{Cite journal |last1=Jolley |first1=S. J. |last2=Freeman |first2=S. R. |last3=Barnicoat |first3=A. C. |last4=Phillips |first4=G. M. |last5=Knipe |first5=R. J. |last6=Pather |first6=A. |last7=Fox |first7=N. P. C. |last8=Strydom |first8=D. |last9=Birch |first9=M. T. G. |last10=Henderson |first10=I. H. C. |last11=Rowland |first11=T. W. |date=2004-06-01 |title=Structural controls on Witwatersrand gold mineralisation |url=https://www.sciencedirect.com/science/article/pii/S0191814103001846 |journal=Journal of Structural Geology |volume=26 |issue=6 |pages=1067–1086 |doi=10.1016/j.jsg.2003.11.011 |bibcode=2004JSG....26.1067J |issn=0191-8141}}</ref> Gold is found in these variable thickness layers of pebble lags, stacked [[Fluvial sediment processes|fluvial]] deposits, and other stratigraphy.<ref name=":04"/><ref name=":02" /> Mponeng specifically,  gold is associated with previously mentioned thrust fracturing and with the following mineralisations:
 * Steep quartz/sulphide-bearing fractures
@@ Line 58: / Line 58: @@
 * Sulphide-bearing fractures
 * Ultracataclastics
-* Mesophased hydrocarbons.<ref name=":02" />
+* Mesophased hydrocarbons<ref name=":02" />
-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.<ref name=":04"/> The VCR and CLR themselves are around 2.7 billion years old, and have experienced lots of deformation and change.<ref>{{Cite journal |last1=Jolley |first1=S.J |last2=Henderson |first2=I.H.C |last3=Barnicoat |first3=A.C |last4=Fox |first4=N.P.C |date=1999 |title=Thrust-fracture network and hydrothermal gold mineralization: Witwatersrand Basin, South Africa |url=https://doi.org/10.1144/GSL.SP.1999.155.01.12 |journal=Geological Society, London, Special Publications |volume=155 |pages=153–165|doi=10.1144/GSL.SP.1999.155.01.12 }}</ref><ref>{{Cite journal |last1=Large |first1=R.R |last2=Meffre |first2=S |last3=Burnett |first3=R |last4=Guy |first4=B |last5=Bull |first5=S |last6=Gilbert |first6=S |last7=Goemann |first7=K |last8=Leonid |first8=D |date=2013 |title=Evidence for an Intrabasinal Source and Multiple Concentration Processes in the Formation of the Carbon Leader Reef, Witwatersrand Supergroup, South Africa |url=https://doi.org/10.2113/econgeo.108.6.1215 |journal=Economic Geology |volume=108 |issue=6 |pages=1215–1241|doi=10.2113/econgeo.108.6.1215 }}</ref>
+As with most mines, Mponeng is limited to the structural control of the geology. The VCR mineralisation is governed by thrust-fracture systems discussed above, largely from the Lower Kliprivierberg age.<ref name=":04"/> The VCR and CLR themselves are around 2.7 billion years old, and have experienced lots of deformation and change.<ref>{{Cite journal |last1=Jolley |first1=S.J |last2=Henderson |first2=I.H.C |last3=Barnicoat |first3=A.C |last4=Fox |first4=N.P.C |date=1999 |title=Thrust-fracture network and hydrothermal gold mineralization: Witwatersrand Basin, South Africa |url=https://doi.org/10.1144/GSL.SP.1999.155.01.12 |journal=Geological Society, London, Special Publications |volume=155 |issue=1 |pages=153–165|doi=10.1144/GSL.SP.1999.155.01.12 |bibcode=1999GSLSP.155..153J }}</ref><ref>{{Cite journal |last1=Large |first1=R.R |last2=Meffre |first2=S |last3=Burnett |first3=R |last4=Guy |first4=B |last5=Bull |first5=S |last6=Gilbert |first6=S |last7=Goemann |first7=K |last8=Leonid |first8=D |date=2013 |title=Evidence for an Intrabasinal Source and Multiple Concentration Processes in the Formation of the Carbon Leader Reef, Witwatersrand Supergroup, South Africa |url=https://doi.org/10.2113/econgeo.108.6.1215 |journal=Economic Geology |volume=108 |issue=6 |pages=1215–1241|doi=10.2113/econgeo.108.6.1215 |bibcode=2013EcGeo.108.1215L }}</ref>
-== Environmental Impacts ==
+== Environmental impacts ==
-South Africa has been dealing with the affects of mining related [[pollution]] for years,  it comes with having such a large mining industry (roughly 8% GDP)<ref>{{Cite web |date=2023-02-02 |title=An Untapped Goldmine: Opportunities for South African Mining |url=https://www.bcg.com/publications/2023/an-untapped-goldmine-opportunities-for-south-african-mining |access-date=2024-04-09 |website=BCG Global |language=en}}</ref>.  In 1998, mining industry contributed nearly 90% of the 533.6 million tons of waste that was produced in the year. <ref name=":18">{{Cite journal |last=Laker |first=Michiel C. |date=June 2023 |title=Environmental Impacts of Gold Mining—With Special Reference to South Africa |journal=Mining |language=en |volume=3 |issue=2 |pages=205–220 |doi=10.3390/mining3020012 |doi-access=free |issn=2673-6489}}</ref> As displayed by the 1998 data, gold mining is the largest single source of pollution in South Africa. This is exaggerated in the Witwatersrand Basin, the basin is home to over 270 tailings storage facilities, covering 18,000 Ha. <ref name=":18" />
+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.<ref>{{Cite web |last=Möncks |first=Tycho |date=2023-02-09 |title=An Untapped Goldmine: Opportunities for South African Mining |url=https://www.bcg.com/publications/2023/an-untapped-goldmine-opportunities-for-south-african-mining |access-date=2024-04-09 |website=BCG Global |language=en}}</ref> In 1998, mining industry contributed nearly 90% of the 533.6 million tons of waste that was produced annually.<ref name=":18">{{Cite journal |last=Laker |first=Michiel C. |date=June 2023 |title=Environmental Impacts of Gold Mining—With Special Reference to South Africa |journal=Mining |language=en |volume=3 |issue=2 |pages=205–220 |doi=10.3390/mining3020012 |doi-access=free |issn=2673-6489}}</ref> According to 1998 data, gold mining is the largest single source of pollution in South Africa.{{Cn|date=April 2024}} A large portion of this occurs in the Witwatersrand Basin, home to over 270 [[tailings]] storage facilities, covering 18,000 Ha.<ref name=":18" />
-Mining comes along 2 main kinds of waste, waste rock piles and [[Tailings|tailing]] storage facilities (TSFs).  <ref name=":18" /> Waste rock piles are the rock that must be removed in order to reach the ore,  which in the case for Mponeng, is quite a lot as the mine is quite deep. <ref name=":172">{{Cite web |last=Praveen |date=2019-06-11 |title=The top ten deepest mines in the world |url=https://www.mining-technology.com/features/feature-top-ten-deepest-mines-world-south-africa/ |access-date=2024-02-17 |website=Mining Technology |language=en-US}}</ref> [[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 highly hazardous chemical properties. <ref name=":18" />  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. <ref name=":18" />  Pollution has been found to persist even after 72 years of mine abandonment. <ref name=":18" />
+Mining creates two main kinds of waste: waste rock piles and tailing storage facilities (TSFs).<ref name=":18" /> 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.<ref name=":172">{{Cite web |last=Praveen |date=2019-06-11 |title=The top ten deepest mines in the world |url=https://www.mining-technology.com/features/feature-top-ten-deepest-mines-world-south-africa/ |access-date=2024-02-17 |website=Mining Technology |language=en-US}}</ref> 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.<ref name=":18" /> Long-term consequences are also of concern, whether the mine activities continue, halt, or a mine is abandoned, these TSFs can pose serious risk the surrounding environment.<ref name=":18" /> Pollution has been found to persist even after 72 years of mine abandonment.<ref name=":18" />
-Beyond the environment, the citizens of the Witwatersrand Basin have been complaining of windblown dust,  most of which originates from partially rehabilitated TSFs. <ref name=":19">{{Cite journal |last1=Mpanza |first1=Mbalenhle |last2=Adam |first2=Elhadi |last3=Moolla |first3=Raeesa |date=January 2020 |title=Dust Deposition Impacts at a Liquidated Gold Mine Village: Gauteng Province in South Africa |journal=International Journal of Environmental Research and Public Health |language=en |volume=17 |issue=14 |pages=4929 |doi=10.3390/ijerph17144929 |doi-access=free |issn=1660-4601 |pmc=7400412 |pmid=32650563}}</ref> Anglo Ashanti began recording meteorological data in 2012,  Harmony gold has since taken over monitoring. <ref name=":19" />  Citizens are concerned surrounding [[Heavy metals|heavy metal]] content as well as [[Silicate mineral|silica]] content, as both pose serious health risk ([[Silicosis]], [[Tuberculosis]], [[Bronchitis]], Chromic Obstructive Pulmonary Disease (COPD), [[lung cancer]]). <ref>{{Cite journal |last=Maseki |first=J. |date=2017 |title=Health risk posed by enriched heavy metals (As, Cd, and Cr) in airborne particles from Witwatersrand gold tailings |url=http://ref.scielo.org/2fdpg8 |journal=Journal of the Southern African Institute of Mining and Metallurgy |volume=117 |issue=7 |pages=663–669 |doi=10.17159/2411-9717/2017/v117n7a8}}</ref> <ref>{{Cite journal |last1=Merget |first1=R. |last2=Bauer |first2=T. |last3=Küpper |first3=H. |last4=Philippou |first4=S. |last5=Bauer |first5=H. |last6=Breitstadt |first6=R. |last7=Bruening |first7=T. |date=2002-01-01 |title=Health hazards due to the inhalation of amorphous silica |url=https://doi.org/10.1007/s002040100266 |journal=Archives of Toxicology |language=en |volume=75 |issue=11 |pages=625–634 |doi=10.1007/s002040100266 |pmid=11876495 |issn=1432-0738}}</ref> A study in 2020 found elevated value of silica and uranium in [[Particulates|PM10]] airborne pollution from TSFs of gold mines in the area.<ref name=":19" />
+Beyond the environment, the citizens of the Witwatersrand Basin have been complaining of windblown dust, most of which originates from partially rehabilitated TSFs. <ref name=":19">{{Cite journal |last1=Mpanza |first1=Mbalenhle |last2=Adam |first2=Elhadi |last3=Moolla |first3=Raeesa |date=January 2020 |title=Dust Deposition Impacts at a Liquidated Gold Mine Village: Gauteng Province in South Africa |journal=International Journal of Environmental Research and Public Health |language=en |volume=17 |issue=14 |pages=4929 |doi=10.3390/ijerph17144929 |doi-access=free |issn=1660-4601 |pmc=7400412 |pmid=32650563}}</ref> Anglo Ashanti began recording meteorological data in 2012  and Harmony Gold has since taken over monitoring after the acquisition in 2020.<ref name=":19" /> Citizens are concerned surrounding [[Heavy metals|heavy metal]] content as well as [[Silicate mineral|silica]] content, as both pose serious health risks ([[silicosis]], [[tuberculosis]], [[bronchitis]], [[chronic obstructive pulmonary disease]] (COPD), [[lung cancer]]).<ref>{{Cite journal |last=Maseki |first=J. |date=2017 |title=Health risk posed by enriched heavy metals (As, Cd, and Cr) in airborne particles from Witwatersrand gold tailings |url=http://ref.scielo.org/2fdpg8 |journal=Journal of the Southern African Institute of Mining and Metallurgy |volume=117 |issue=7 |pages=663–669 |doi=10.17159/2411-9717/2017/v117n7a8}}</ref><ref>{{Cite journal |last1=Merget |first1=R. |last2=Bauer |first2=T. |last3=Küpper |first3=H. |last4=Philippou |first4=S. |last5=Bauer |first5=H. |last6=Breitstadt |first6=R. |last7=Bruening |first7=T. |date=2002-01-01 |title=Health hazards due to the inhalation of amorphous silica |url=https://doi.org/10.1007/s002040100266 |journal=Archives of Toxicology |language=en |volume=75 |issue=11 |pages=625–634 |doi=10.1007/s002040100266 |pmid=11876495 |issn=1432-0738}}</ref> A study in 2020 found elevated value of silica and uranium in [[Particulates|PM10]] airborne pollution from TSFs of gold mines in the area.<ref name=":19" />
-In South Africa heavy metal pollution from mining industry is the leading cause of soil and water pollution. <ref name=":18" /> The pollution stems from a few sources<ref name=":18" /><ref name=":19" />:
+In South Africa, heavy metal pollution from mining industry is the leading cause of soil and water pollution.<ref name=":18" /> The pollution stems from a few sources:<ref name=":18" /><ref name=":19" />
-* [[Acid mine drainage|Acid Mine Drainage]] (AMD)
+* [[Acid mine drainage]] (AMD)
 * [[Soil salinity|Salinization]]
-* Elevated levels of Potentially Toxic Elements (PTEs)
+* Elevated levels of potentially toxic elements (PTE)
 ** Mainly heavy metals, also including arsenic ([[metalloid]]).
-* Airborne/Dust
+* Airborne dust
-=== Moving Forward ===
+=== 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. <ref name=":18" />  That doesn't mean efforts aren't or can't be made.
+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. <ref name=":18" />
-Immobilizing the PTEs in the TSFs is a main focus of pollution prevention and control. <ref name=":18" />
+Immobilizing the PTEs in the TSFs is a main focus of pollution prevention and control.<ref name=":18" />
-* [[Liming (soil)|Liming]] the acidic tailings to a suitable pH (>5.5) can significantly reduce the mobility of cationic PTEs.  This requires large amount of lime.
+* [[Liming (soil)|Liming]] the acidic tailings to a suitable pH (>5.5) can significantly reduce the mobility of cationic PTEs. This requires large amount of lime.
 * Application of clays or organic matter with high cation capacity, with goal of PTE absorption.
 * Application of [[Sesquioxide|sesquioxides]] (M<sub>2</sub>O<sub>3</sub>) which would immobilize oxy-anionic PTEs.
-* Application of [[Hydroxide|Hydroxides]] or [[Phosphate|phosphates]],  similar effect of liming.
+* Application of [[Hydroxide|hydroxides]] or [[Phosphate|phosphates]],  similar effect of liming.
-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. <ref>{{Cite journal |last1=Rösner |first1=T. |last2=van Schalkwyk |first2=A. |date=2000-10-01 |title=The environmental impact of gold mine tailings footprints in the Johannesburg region, South Africa |url=https://doi.org/10.1007/s100640000037 |journal=Bulletin of Engineering Geology and the Environment |language=en |volume=59 |issue=2 |pages=137–148 |doi=10.1007/s100640000037 |issn=1435-9537}}</ref>
+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.<ref>{{Cite journal |last1=Rösner |first1=T. |last2=van Schalkwyk |first2=A. |date=2000-10-01 |title=The environmental impact of gold mine tailings footprints in the Johannesburg region, South Africa |url=https://doi.org/10.1007/s100640000037 |journal=Bulletin of Engineering Geology and the Environment |language=en |volume=59 |issue=2 |pages=137–148 |doi=10.1007/s100640000037 |bibcode=2000BuEGE..59..137R |issn=1435-9537}}</ref>
 == Seismicity ==
-[[Seismicity]] in mines is common as removing mass amounts of rock can change stress dynamics, especially if pre-existing [[Fault (geology)|faults]] exist.<ref name=":9">{{Cite journal |last1=Li |first1=T. |last2=Cai |first2=M.F. |last3=Cai |first3=M. |date=December 2007 |title=A review of mining-induced seismicity in China |url=https://doi.org/10.1016/j.ijrmms.2007.06.002 |journal=International Journal of Rock Mechanics and Mining Sciences |volume=44 |issue=8 |pages=1149–1171 |doi=10.1016/j.ijrmms.2007.06.002 |bibcode=2007IJRMM..44.1149L |issn=1365-1609}}</ref> This seismicity is termed 'mining-induced seismicity' are still the release of elastic strain but are often low moment magnitude.<ref name=":9" /><ref name=":12">{{Cite journal |last1=Richardson |first1=Eliza |last2=Jordan |first2=Thomas H. |date=2002 |title=Seismicity in Deep Gold Mines of South Africa: Implications for Tectonic Earthquakes |url=https://doi.org/10.1785/0120000226 |journal=Bulletin of the Seismological Society of America |volume=92 |issue=5 |pages=1766–1782|doi=10.1785/0120000226 |bibcode=2002BuSSA..92.1766R }}</ref> 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.<ref name=":9" /><ref name=":12" />
+[[Seismicity]] in mines is common as removing mass amounts of rock can change stress dynamics, especially if pre-existing [[Fault (geology)|faults]] exist.<ref name=":9">{{Cite journal |last1=Li |first1=T. |last2=Cai |first2=M.F. |last3=Cai |first3=M. |date=December 2007 |title=A review of mining-induced seismicity in China |url=https://doi.org/10.1016/j.ijrmms.2007.06.002 |journal=International Journal of Rock Mechanics and Mining Sciences |volume=44 |issue=8 |pages=1149–1171 |doi=10.1016/j.ijrmms.2007.06.002 |bibcode=2007IJRMM..44.1149L |issn=1365-1609}}</ref> This seismicity is termed 'mining-induced seismicity', caused by the release of elastic strain but are often low moment magnitude.<ref name=":9" /><ref name=":12">{{Cite journal |last1=Richardson |first1=Eliza |last2=Jordan |first2=Thomas H. |date=2002 |title=Seismicity in Deep Gold Mines of South Africa: Implications for Tectonic Earthquakes |url=https://doi.org/10.1785/0120000226 |journal=Bulletin of the Seismological Society of America |volume=92 |issue=5 |pages=1766–1782|doi=10.1785/0120000226 |bibcode=2002BuSSA..92.1766R }}</ref> 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.<ref name=":9" /><ref name=":12" />
-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 event in which 3 were killed.'''<ref>{{Cite web |last=Reporter |first=Creamer Media |title=Three killed in fall of ground at AngloGold's Mponeng |url=https://www.miningweekly.com/article/workers-trapped-at-mponeng-following-seismic-event-2020-03-06 |access-date=2024-03-12 |website=Mining Weekly |language=en}}</ref>''' In deep mines, vertical stress can reach an astounding 80-100 MPa, equivalent to roughly 10&nbsp;km under water.<ref>{{Cite web |last=US Department of Commerce |first=National Oceanic and Atmospheric Administration |title=How does pressure change with ocean depth? |url=https://oceanservice.noaa.gov/facts/pressure.html |access-date=2024-03-08 |website=oceanservice.noaa.gov |language=EN-US}}</ref><ref name=":3">{{Cite journal |last1=Ziegler |first1=Moritz |last2=Reiter |first2=Karsten |last3=Heidbach |first3=Oliver |last4=Zang |first4=Arno |last5=Kwiatek |first5=Grzegorz |last6=Stromeyer |first6=Dietrich |last7=Dahm |first7=Torsten |last8=Dresen |first8=Georg |last9=Hofmann |first9=Gerhard |date=2015-10-01 |title=Mining-Induced Stress Transfer and Its Relation to a M1.9 Seismic Event in an Ultra-deep South African Gold Mine |url=https://doi.org/10.1007/s00024-015-1033-x |journal=Pure and Applied Geophysics |language=en |volume=172 |issue=10 |pages=2557–2570 |doi=10.1007/s00024-015-1033-x |s2cid=199492287 |issn=1420-9136}}</ref><ref>{{Cite journal |last1=Kozłowska |first1=Maria |last2=Orlecka-Sikora |first2=Beata |last3=Kwiatek |first3=Grzegorz |last4=Boettcher |first4=Margaret S. |last5=Dresen |first5=Georg |date=19 December 2014 |title=Nanoseismicity and picoseismicity rate changes from static stress triggering caused by a M w 2.2 earthquake in Mponeng gold mine, South Africa |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1002/2014JB011410 |journal=Journal of Geophysical Research: Solid Earth |language=en |volume=120 |issue=1 |pages=290–307 |doi=10.1002/2014JB011410 |issn=2169-9313 |via=AGU}}</ref><ref>{{Cite journal |last1=Kwiatek |first1=G. |last2=Plenkers |first2=K. |last3=Nakatani |first3=Y. |last4=Yabe |first4=Y. |last5=Dresen |first5=G. |date=2010 |title=Frequency-Magnitude Characteristics Down to Magnitude -4.4 for Induced Seismicity Recorded at Mponeng Gold Mine, South Africa |url=https://doi.org/10.1785/0120090277 |journal=Bulletin of the Seismological Society of America |volume=100 |issue=3 |pages=1165–1173 |doi=10.1785/0120090277 |bibcode=2010BuSSA.100.1165K |via=GeoScienceWorld}}</ref> Seismicity in deep gold mines is common, and is often induced by mining activities.<ref name=":2">{{Cite journal |last1=Riemer |first1=K. L. |last2=Durrheim |first2=R. J. |date=2012-09-25 |title=Mining seismicity in the Witwatersrand Basin: monitoring, mechanisms and mitigation strategies in perspective |journal=Journal of Rock Mechanics and Geotechnical Engineering |volume=4 |issue=3 |pages=228–249 |doi=10.3724/SP.J.1235.2012.00228 |issn=1674-7755|doi-access=free |bibcode=2012JRMGE...4..228R }}</ref><ref name=":12"/> Two events can be considered:<ref name=":12"/>
+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.'''<ref>{{Cite web |last=Reporter |first=Creamer Media |title=Three killed in fall of ground at AngloGold's Mponeng |url=https://www.miningweekly.com/article/workers-trapped-at-mponeng-following-seismic-event-2020-03-06 |access-date=2024-03-12 |website=Mining Weekly |language=en}}</ref>''' In deep mines, vertical stress can reach 80-100 MPa, equivalent to roughly 10&nbsp;km under water.<ref>{{Cite web |last=US Department of Commerce |first=National Oceanic and Atmospheric Administration |title=How does pressure change with ocean depth? |url=https://oceanservice.noaa.gov/facts/pressure.html |access-date=2024-03-08 |website=oceanservice.noaa.gov |language=EN-US}}</ref><ref name=":3">{{Cite journal |last1=Ziegler |first1=Moritz |last2=Reiter |first2=Karsten |last3=Heidbach |first3=Oliver |last4=Zang |first4=Arno |last5=Kwiatek |first5=Grzegorz |last6=Stromeyer |first6=Dietrich |last7=Dahm |first7=Torsten |last8=Dresen |first8=Georg |last9=Hofmann |first9=Gerhard |date=2015-10-01 |title=Mining-Induced Stress Transfer and Its Relation to a M1.9 Seismic Event in an Ultra-deep South African Gold Mine |url=https://doi.org/10.1007/s00024-015-1033-x |journal=Pure and Applied Geophysics |language=en |volume=172 |issue=10 |pages=2557–2570 |doi=10.1007/s00024-015-1033-x |s2cid=199492287 |issn=1420-9136}}</ref><ref>{{Cite journal |last1=Kozłowska |first1=Maria |last2=Orlecka-Sikora |first2=Beata |last3=Kwiatek |first3=Grzegorz |last4=Boettcher |first4=Margaret S. |last5=Dresen |first5=Georg |date=19 December 2014 |title=Nanoseismicity and picoseismicity rate changes from static stress triggering caused by a M w 2.2 earthquake in Mponeng gold mine, South Africa |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1002/2014JB011410 |journal=Journal of Geophysical Research: Solid Earth |language=en |volume=120 |issue=1 |pages=290–307 |doi=10.1002/2014JB011410 |issn=2169-9313 |via=AGU}}</ref><ref>{{Cite journal |last1=Kwiatek |first1=G. |last2=Plenkers |first2=K. |last3=Nakatani |first3=Y. |last4=Yabe |first4=Y. |last5=Dresen |first5=G. |date=2010 |title=Frequency-Magnitude Characteristics Down to Magnitude -4.4 for Induced Seismicity Recorded at Mponeng Gold Mine, South Africa |url=https://doi.org/10.1785/0120090277 |journal=Bulletin of the Seismological Society of America |volume=100 |issue=3 |pages=1165–1173 |doi=10.1785/0120090277 |bibcode=2010BuSSA.100.1165K |via=GeoScienceWorld}}</ref> Seismicity in deep gold mines is common, and is often induced by mining activities.<ref name=":12" /><ref name=":2">{{Cite journal |last1=Riemer |first1=K. L. |last2=Durrheim |first2=R. J. |date=2012-09-25 |title=Mining seismicity in the Witwatersrand Basin: monitoring, mechanisms and mitigation strategies in perspective |journal=Journal of Rock Mechanics and Geotechnical Engineering |volume=4 |issue=3 |pages=228–249 |doi=10.3724/SP.J.1235.2012.00228 |issn=1674-7755|doi-access=free |bibcode=2012JRMGE...4..228R }}</ref> Two events can be considered:<ref name=":12"/>
 * Type A - low moment magnitude (<1), clustered in time and space, within 100m of mining surface.
@@ Line 100: / Line 100: @@
 === Research ===
-One way to move forward is a better understanding of [[rock burst]] and excavation methods. A better understanding can provide better safety protocols.<ref>{{Cite journal |last1=Li |first1=T. |last2=Cai |first2=M. F. |last3=Cai |first3=M. |date=2007-12-01 |title=A review of mining-induced seismicity in China |url=https://www.sciencedirect.com/science/article/pii/S1365160907000810 |journal=International Journal of Rock Mechanics and Mining Sciences |volume=44 |issue=8 |pages=1149–1171 |doi=10.1016/j.ijrmms.2007.06.002 |bibcode=2007IJRMM..44.1149L |issn=1365-1609}}</ref> A prominent use of deep mines and their associated, often low magnitude, earthquakes is to connect laboratory scale experiments to real world situations.<ref name=":72">{{Cite journal |last1=Kwiatek |first1=G |last2=Plenkers |first2=K |last3=Nakatani |first3=M |last4=Yabe |first4=Y |last5=Dressen |first5=G |last6=JAGUARS-Group |date=2010 |title=Frequency-Magnitude Characteristics Down to Magnitude -4.4 for Induced Seismicity Recorded at Mponeng Gold Mine, South Africa |url=https://doi.org/10.1785/0120090277 |journal=Bulletin of the Seismological Society of America |volume=100 |issue=3 |pages=1165–1173 |doi=10.1785/0120090277 |bibcode=2010BuSSA.100.1165K |via=GeoScienceWorld}}</ref><ref name=":82">{{Cite journal |last1=Kwiatek |first1=G |last2=Plenkers |first2=K |last3=Drensen |first3=G |last4=JAGUARS Research Group |date=2011 |title=Source Parameters of Picoseismicity Recorded at Mponeng Deep Gold Mine, South Africa: Implications for Scaling Relations |url=https://doi.org/10.1785/0120110094 |journal=Bulletin of the Seismological Society of America |volume=101 |issue=6 |pages=2592–2608 |doi=10.1785/0120110094 |bibcode=2011BuSSA.101.2592K |via=GeoScienceWorld}}</ref> There is also considerable research trying to understand nucleation of said earthquakes,<ref name=":72" /> and whether they work the same as larger earthquakes.<ref name=":82" /> In Mponeng, JAGUARS (Japanese-German Acoustic Emissions Research in South Africa)<ref>{{Cite web |title=JAGUARS – induced.pl |url=https://www.induced.pl/research/jaguars |access-date=2024-03-08 |website=www.induced.pl}}</ref> has emplaced a network of accelerometers and piezoelectric acoustic emissions sensors.<ref name=":72" /> These sensors can record very small moment magnitude earthquakes, capable of recording events with frequencies from 0.7&nbsp;kHz to 200&nbsp;kHz (M<0.5).<ref name=":102"/> In a one year period, 2007-2008,  nearly 500,000 events were recorded, most of which with low (sub 25&nbsp;kHz) frequencies.<ref name=":102"/> The JAGUARS network in placed below the Ventersdorp Contact Reef, there are eight [[Acoustic emission|Acoustic Emissions]] sensors, two [[strainmeter]]s, and one triaxial [[accelerometer]] that make up the network.<ref name=":102"/>
+One way to move forward is a better understanding of [[rock burst]] and excavation methods. A better understanding can provide better safety protocols.<ref>{{Cite journal |last1=Li |first1=T. |last2=Cai |first2=M. F. |last3=Cai |first3=M. |date=2007-12-01 |title=A review of mining-induced seismicity in China |url=https://www.sciencedirect.com/science/article/pii/S1365160907000810 |journal=International Journal of Rock Mechanics and Mining Sciences |volume=44 |issue=8 |pages=1149–1171 |doi=10.1016/j.ijrmms.2007.06.002 |bibcode=2007IJRMM..44.1149L |issn=1365-1609}}</ref> A prominent use of deep mines and their associated, often low magnitude, earthquakes is to connect laboratory scale experiments to real world situations.<ref name=":72">{{Cite journal |last1=Kwiatek |first1=G |last2=Plenkers |first2=K |last3=Nakatani |first3=M |last4=Yabe |first4=Y |last5=Dressen |first5=G |last6=JAGUARS-Group |date=2010 |title=Frequency-Magnitude Characteristics Down to Magnitude -4.4 for Induced Seismicity Recorded at Mponeng Gold Mine, South Africa |url=https://doi.org/10.1785/0120090277 |journal=Bulletin of the Seismological Society of America |volume=100 |issue=3 |pages=1165–1173 |doi=10.1785/0120090277 |bibcode=2010BuSSA.100.1165K |via=GeoScienceWorld}}</ref><ref name=":82">{{Cite journal |last1=Kwiatek |first1=G |last2=Plenkers |first2=K |last3=Drensen |first3=G |last4=JAGUARS Research Group |date=2011 |title=Source Parameters of Picoseismicity Recorded at Mponeng Deep Gold Mine, South Africa: Implications for Scaling Relations |url=https://doi.org/10.1785/0120110094 |journal=Bulletin of the Seismological Society of America |volume=101 |issue=6 |pages=2592–2608 |doi=10.1785/0120110094 |bibcode=2011BuSSA.101.2592K |via=GeoScienceWorld}}</ref> There is also considerable research trying to understand nucleation of said earthquakes,<ref name=":72" /> and whether they work the same as larger earthquakes.<ref name=":82" /> In Mponeng, JAGUARS (Japanese-German Acoustic Emissions Research in South Africa)<ref>{{Cite web |title=JAGUARS – induced.pl |url=https://www.induced.pl/research/jaguars |access-date=2024-03-08 |website=www.induced.pl}}</ref> has emplaced a network of accelerometers and piezoelectric acoustic emissions sensors.<ref name=":72" /> These sensors can record very small moment magnitude earthquakes, capable of recording events with frequencies from 0.7&nbsp;kHz to 200&nbsp;kHz (M<0.5).<ref name=":102"/> In a one year period, 2007-2008,  nearly 500,000 events were recorded, most of which with low (sub 25&nbsp;kHz) frequencies.<ref name=":102"/> The JAGUARS network is placed below the Ventersdorp Contact Reef, there are eight [[Acoustic emission|Acoustic Emissions]] sensors, two [[strainmeter]]s, and one triaxial [[accelerometer]] that make up the network.<ref name=":102"/>
-==In popular culture==
-[[File:Millán Ludeña en 2017.jpg|thumb|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.<ref>{{Citation |title=South Africa's Mponeng Gold Mine |date=2010-05-13 |url=https://www.imdb.com/title/tt1630761/?ref_=ttpl_ov |access-date=2024-03-08 |series=Build It Bigger |others=Danny Forster}}</ref>
-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.<ref>{{cite web|url=https://www.aa.com.tr/en/americas/ecuadorian-sets-record-in-run-4-000m-below-surface/917320 |title=Ecuadorian sets record in run 4,000m below surface |date=23 September 2017 |first=Sergio |last=García |work=Anadolu Agency}}</ref> It was Millan's goal to run as far, and as close to sun as he could.  Later, after Mponeng, Millan run up Mt.Chimborazo in Ecuador.<ref>{{Cite web |date=2019-09-05 |title=This Endurance Athlete Finished Three of the Most Challenging Races on Earth |url=https://www.menshealth.com/uk/fitness/a28925142/lets-do-this-challenge-awards/ |access-date=2024-03-08 |website=Men's Health |language=en-GB}}</ref> Millan has a movie called 'From Core to Sun' released in 2018 about his achievements.<ref>{{Citation |last=Garland |first=Oliver Lee |title=From Core to Sun |date=2018-06-01 |type=Documentary |url=https://www.imdb.com/title/tt7379662/ |access-date=2024-03-08 |publisher=Levector, Levector}}</ref>
 == See also ==
 * [[Gold mining|Gold Mines]]
-* [[South Africa]]
 * [[Witwatersrand]]
-* [[Gold]]
 * [[Seismicity]]
-* [[Earthquake]]s
 * [[Tailings]]
-* [[Gauteng|Gauteng Province]]
+* [[Gauteng]]
-* [[Acid mine drainage|Acid Mine Drainage]]
+* [[Acid mine drainage]]
+{{commons category|Mponeng Gold Mine}}
+{{clear}}
 ==References==
-{{commons category|Mponeng Gold Mine}}
 {{reflist}}