- Quake hits Klerksdorp
- Single Stilfontein Sugar Daddies interested in Sugar Daddies Dating, Sugar Daddy BBW
- Signup for a 100% Free Profile to Browse every member
- Create a Free Account to Search all Members
- Single North-West (South Africa) Guys Seeking Shemales Interested In Shemale Dating
Mwazvita T. Dalu, Amanda Manyani, Current Masunungure. Urban Food Security. Urban Renewal in South African Cities.
Quake hits Klerksdorp
About this book Introduction This book embraces South Africa and its place in the Global South, providing a succinct theoretical and empirical analysis and discussion of urban issues in the country. There have been sporadic calls from the Urban Geography community for the development of an overarching and comprehensive text that explores contemporary processes and practices taking place in urban South Africa and, more widely, the Global South.
This is an edited collection of chapters by leading urban theorists and practitioners working on various themes within urban South Africa and serves as a base for scholars and students interested in urban perspectives from countries in the Global South. Age: 36 South Africa, Durban.
Single Stilfontein Sugar Daddies interested in Sugar Daddies Dating, Sugar Daddy BBW
Age: 37 South Africa, Pretoria. Age: 35 South Africa, Pretoria. Age: 32 South Africa, Stilfontein. Age: 34 South Africa, Fochville. Age: 31 South Africa, Bloemfontein. Age: 40 South Africa, Cape Town. Age: 31 South Africa, Johannesburg. Age: 35 South Africa, Bloemfontein. Age: 36 South Africa, Pretoria.
Seismicity, associated with lead-lags, was identified from mine seismic catalogues. Moment tensor inversions were used to calculate the source mechanisms of the lead-lag events. Fault plane solutions were used to confirm the selected seismicity as lead-lags events and to determine the focal mechanisms. The ambiguity of fault plane solutions was resolved using the Doppler shift in corner frequencies.
The term 'remnant' refers to reef that has not been mined, owing to low grades, or the presence of hazardous geological features. This project investigated the rock mass behaviour occurring within remnant blocks in an attempt to quantify the hazard. This current project aims to evaluate the design criteria of regularly spaced dip pillars and to identify the conditions under which RSDP mining works best as a rockburst control method. The observed long-term tilt and strain will be compared with elastic and inelastic results, obtained by modelling using MINF. The programme encompasses both fundamental research on topics such as seismic source mechanisms, the dynamics of fault zones and rock burst damage mechanisms, and applied research on methods to estimate seismic hazard and to assess the vulnerability of excavations to rockburst damage.
The deep mines in South Africa are unique in the world, as they represent the only place on the globe where ruptures that are related to earthquakes and seismic events can be viewed and studied in situ. GoafWarn can monitor micro-seismicity associated with the formation and extension of fractures prior to the collapse of the roof strata. Recent research in coal mines using this event-detection device has been successful in giving warnings prior to goafing.
Signup for a 100% Free Profile to Browse every member
It is envisaged that this technology could reduce accidents and, in exceptional circumstances, prevent damage to infrastructure. Considerable progress has been made by CSIR scientists in the study of strong ground motion and site effect surrounding underground mining excavations. A stand-alone instrument, known as the Peak Velocity Detector PVD , specially designed for recording strong ground motions underground, was used to create a large database of peak particle velocities measured on stope hangingwalls. The peak particle velocities were measured at the surface of the excavations.
The data recorded on the skin of the excavations were compared with those measured by the mine's seismic networks to determine the site response. Another unique and recently established research field is that of in-stope micro-seismic monitoring. This encapsulates a wide range of research, such as regional and local support behaviour, the mechanism of pillar failure, 23 quasi-static and dynamic deformations of the rocks, 24 as well as rockburst and rockfall control.
- dating locations near Robertson South Africa.
- Single Stilfontein Men Over 50 interested in Over 50 Dating, Over 50 Sex Dating?
- Create a Free Account to Browse all Members;
- male dating Winburg South Africa.
- singles dating site Plettenberg Bay South Africa!
- best hook up spots Embalenhle South Africa.
The RaSiM symposia are held every four years and are regarded as the best single source of papers on mining-induced seismicity. South Africans have followed their colleagues in other countries by concentrating their efforts on publishing on mining-induced seismicity in the RaSiM proceedings. The sixth RaSiM symposium, held in Perth, Australia, in , included a wide range of papers from South Africa, on such topics as: assessing the success or otherwise of mine layout design, 25,26 failure mechanisms, 23 and providing hazard assessment on a daily or even hourly basis.
Most of the South African papers were on seismicity or rockbursts in deep-level gold mines, although four articles were related to other types of mining, namely underground platinum 23,28 and copper 29 as well as open-pit mining. This congress was held in South Africa in September Although the focus was mostly on rock mechanics, nine papers by South Africans on mining seismology research and case studies were presented on a wide variety of topics.
Create a Free Account to Search all Members
These were strong ground motion and site response; 31 improved seismic location methods; 32 seismic hazard assessment methods; 33 seismic risk of mining layouts; 34,35 the fractography of rockbursts and impact structures; 36 the dynamic failure of pillar remnants; 37 and dynamic numerical modelling. The aim of the seminar, which was held in Johannesburg in , was to gather the latest information on mining conditions in deep and high stress situations.
In addition to seismicity, issues such as cooling and ventilation were also addressed. Papers by South African authors, with a significant seismological component, included a seismic and modelling analysis of dip-pillar mining, 41 a laboratory investigation of the rock-mass response to mining, 42 a case study of rockburst mechanisms, 43 and a description of strategies to manage seismicity at depth. Investigation into the risks posed by large seismic events in gold mining areas.
Single North-West (South Africa) Guys Seeking Shemales Interested In Shemale Dating
A large seismic event, with a magnitude of 5. The event damaged several buildings and injured 58 people in the nearby town of Stilfontein Fig. Two mineworkers were killed and others had to be evacuated. It was the largest mining-related seismic event ever to occur in South Africa.
- North-West BBW | SSBBW North-West | BBW Dating North-West | BBW North-West | BBW in North-West?
- date hookup Koppies South Africa.
- AdultFriendFinder: Free Sex Dating in Orkney, Province of North West!
- free dating services Midrand South Africa.
- just dating in Ekangala South Africa!
- Single Stilfontein Guys interested in Cheating Sex Partners Dating, Cheating Sex Partner.
Durrheim, to investigate the risks to miners, mines, and the public posed by large seismic events in the gold mining districts. It was found that the event of 9 March could be ascribed to past mining. The possibility that the event and its aftershocks were solely due to natural forces was considered to be extremely small.
Seismic events will continue to occur as long as there is mining, and for some time after mining ceases, as earthquakes are likely to be triggered when worked-out mines flood. It is unlikely that the magnitudes of the events and intensity of the shaking would be significantly greater than the levels that have been experienced to date.
Nevertheless, the recommendation is that seismic monitoring networks be improved, and that monitoring continues after mines close. The seismic hazard should be taken into account when the future use of mining land is being considered or new buildings are designed. Municipalities are aware of the risks posed by seismicity, and are incorporating these risks in their disaster management plans.
South Africa has been a pioneer in adapting the reflection seismic method to the hard rock environment to explore for gold and platinum deposits. Two review papers were included in a special volume on hard rock seismic exploration published by the Society of Exploration Geophysicists. Seismological results have also motivated additional work in other fields. Recent research has demonstrated the value of seismically determined crustal thickness values, for assessing the isostatic response to the load of the Bushveld Complex in the crust. The platinum resources of southern Africa would greatly increase if the Bushveld Complex can be shown to have economic horizons at shallow depth in its centre.
Surprisingly little research has been conducted on the 3D geometry of the Bushveld Complex, for such an economically important resource. Research Vibroseis lines should ideally be collected across the entire extent of the complex, to delineate fully this important resource. A less expensive alternative would be the placement of an array of passive broadband seismometers, focused on resolving crustal structure. In another research project using crustal thickness results 51 and seismic velocity variations 52 beneath the Kaapvaal Craton, it has been shown that the crustal thickness variations at the Moho give a strong contribution to the gravity signal of southern Africa.
The contribution to the gravity signal from the seismic velocity variations in the mantle is, surprisingly, about the same order of magnitude as the gravity variations due to the Moho variations. However, the seismic velocity variations in the mantle keel beneath the Kaapvaal Craton appear to be dominated by composition variations as opposed to more commonly supposed temperature variations. These gravity models lend additional support to the isopycnic hypothesis, 20 which proposes that Archean cratons are underlain by thick, depleted mantle keels with relatively high magnesium content.
The location accuracy of data recorded by the network has been improved by replacing the short-period instruments with broadband and extended short-period seismometers, as well as by developing a multi-reference relocation technique. Stable source parameter calculation methods have been developed for the data recorded by the SANSN, and a large body of research on seismic hazard and risk for sites of essential engineering structures has been completed.
Two short-period instruments have been installed in the gold mining areas of the Central Rand and Far West Rand to improve the accuracy of locating mine tremors. Several MHSC research projects involving large components of mining seismology research have been completed. The highlights include insights into the behaviour of crush pillars, further work on the integration of seismicity and numerical modelling, research in proactive approaches to rock mass stability, the quantification of the effects of various lead-lag distances between adjacent panels on fracturing, stability, support and seismicity, and new methods for quantifying the hazards association with remnant extraction.
Devices to detect seismic events have been developed to give prior warnings of goafing in coal mines and falls of ground in platinum mines. The site response has been evaluated from measurements of peak ground velocity of the skin of excavations, which was found to be on average nine times higher than the velocity in the rock mass, as inferred from the in-mine networks. New models of the structure of the Bushveld Complex have used seismically determined values of the crustal thickness to assess the isostatic response to the load of the complex in the crust, and postulate the existence of economic horizons in the centre of the complex.
The consequences of this research have the potential to increase greatly the platinum resources of southern Africa. Graham G. Council for Geoscience, Pretoria. Durrheim R. The risks to miners, mines, and the public posed by large seismic events in the gold mining districts of South Africa. Potvin, J. Hadjigeorgiou and D. Stacey, pp.
Australian Centre for Geomechanics, Perth. Nyblade A. White Paper. Online: www. Cichowicz A. Automatic processing and relocation methods. Controlling Seismic Risk, Proc. Bejaichund M. CGS Report No. Kijko A. Estimation of the maximum earthquake magnitude, m max. Pure Appl.