A5041419986- Seismic Imaging and Inversion Techniques
- Seismic Waves and Analysis
- earthquake and tectonic studies
- Drilling and Well Engineering
- Rock Mechanics and Modeling
- Geotechnical and Geomechanical Engineering
- Geological and Geophysical Studies
- Geophysical Methods and Applications
- Geological and Geochemical Analysis
- High-pressure geophysics and materials
- Seismology and Earthquake Studies
- Geophysical and Geoelectrical Methods
- Geochemistry and Geologic Mapping
- Geological Modeling and Analysis
- Mining Techniques and Economics
- Earthquake Detection and Analysis
- Geological formations and processes
- Mineral Processing and Grinding
- Reservoir Engineering and Simulation Methods
- Landslides and related hazards
- Tunneling and Rock Mechanics
- Hydraulic Fracturing and Reservoir Analysis
- Geoscience and Mining Technology
- Hydrocarbon exploration and reservoir analysis
- Geophysics and Gravity Measurements
University of the Witwatersrand
2015-2024
Continental (Germany)
2019
Geomechanica (Canada)
2019
Institute of Seismology
2019
Alexion Pharma (Switzerland)
2019
Japan Science and Technology Agency
2019
Universidade do Estado do Pará
2017
Council for Scientific and Industrial Research
2007-2015
Canadian Society of Intestinal Research
2015
International Union of Geological Sciences
2013
Several recent models of crustal evolution are based on the belief that thickness continental crust is proportional to its age, with ancient being thickest. A worldwide review seismic structure contradicts this and falsifies these models, at least for Archean. Proterozoic has a 40–55 km substantial high‐velocity (>7 km/s) layer base, while Archean only 27–40 thick (except site younger rifts collisional boundaries) lacks basal layer. Seismology also provides evidence lithosphere thickest...
Research Article| June 01, 1991 Archean and Proterozoic crustal evolution: Evidence from seismology Raymond J. Durrheim; Durrheim 1Geophysics Department, University of the Witwatersrand, Johannesburg, Wits 2050, South Africa Search for other works by this author on: GSW Google Scholar Walter D. Mooney 2U.S. Geological Survey, 345 Middlefield Road, MS 977, Menlo Park, California 94025 Author Article Information Publisher: Society America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print...
Due to high metal prices and increased difficulties in finding shallower deposits, the exploration for exploitation of mineral resources is expected move greater depths. Consequently, seismic methods will become a more important tool help unravel structures hosting deposits at great depth mine planning exploration. These also can be used with varying degrees success directly target depth. We review contributions that have been made developing these techniques mining industry focus on four...
The concept of the 4th industrial revolution is becoming a strategic determinant sustainability, success and competitiveness in modern mining sector. importance digital transformation industry has long been debated, hampered part by conservative nature Much debate focused on choosing suitable techniques that provide acceptable levels ore/waste selectivity, scale implementation, cost reduction metallurgical extraction techniques. purpose this review to give an overview minerals extractive...
The nature of the lower crust across southern African shield has been investigated by jointly inverting receiver functions and Rayleigh wave group velocities for 89 broadband seismic stations located in Botswana, South Africa Zimbabwe. For large parts both Archaean Proterozoic terrains, velocity models obtained from inversions show shear ≥4.0 km/s below ∼20–30 km depth, indicating a predominantly mafic crust. However, much Kimberley terrain adjacent Kheis Province Witwatersrand Africa, as...
Inrushes of ground water and the ignition flammable gases pose risks to workers in deep South African gold mines. Large volumes may be stored solution cavities dolomitic rocks that overlie Black Reef (BLR) Formation, while there are several possible sources for methane, namely, coal seams, kerogen found some ore bodies, or methane introduced by igneous intrusions. Potential conduits transport underground workings were mapped using 3D reflection seismic data. Edge detection attributes...
Mineral resources are important contributors to the global economy and societal wellbeing. Directly, they provide employment, revenue taxes through extraction, processing sale of minerals. Indirectly, essential all modern industries, including: energy, manufacturing, construction, biotic abiotic resource extraction agriculture. The principle that 'one cannot understand value what have until measure it' is particularly relevant with critical raw materials (CRMs). CRM a concept categorises...
The FUTURE project aims to enhance seismic surveying in South African mining by integrating advanced acquisition technologies. In this paper, we detail surface and underground surveys at the Deep gold mine as part of project. Surface used co-located broadband micro-electromechanical sensors, one three component recorders connected geophones, distributed acoustic sensing using a straight fibre optic cable, along with 6 ton vibrator operating 4-180 Hz linear sweeps. addition, employed...
Selecting ground motion prediction models (GMPM) is crucial in assessing seismic hazard levels a specific region. This study investigates the influence of model (GMM) selection on assessment Johannesburg, South Africa. Most events affecting Johannesburg are related to mining activities and water ingress into underground mine voids. The most seismically active regions Africa include areas around Klerksdorp, Welkom, Carletonville. These experience significant number earthquakes, with being...
On 5 August 2014, the Orkney M5.5 earthquake, largest in South African gold mining districts, occurred with an unusual strike-slip mechanism at great depth of 4.78 km below surface. In a rare case, ML 5.5 earthquake within area covered by legacy 2D and 3D reflection seismic data acquired 1990s 2000s for exploration mine development. addition, rupture plane was recorded accurately delineated underground in-mine network near source region. The integration seismicity allowed us to identify...
The structure of the central Kaapvaal Craton southern Africa has been investigated by deep seismic sounding, using mine tremors as energy sources. Seismometers were deployed at approximately 10km intervals on two profiles stretching between major tremor source regions. Mine are rich in shear enabling joint interpretation P- and S-waves produce substantial frequencies low 1 Hz. Record sections presented for both S-waves, traveltimes amplitudes interpreted 2-D ray-tracing techniques. Synthetic...
The Namaqualand Metamorphic Complex forms part of the Precambrian shield southern Africa, and hosts several major base metal deposits. A long line seismic refraction experiment traversing was conducted in order to complement geological geophysical studies structure evolution this region. Seismograms were obtained at approximately 10 km intervals along 290 profile. Seismic ray‐tracing techniques used model travel‐time amplitude data. It found that lower crust is comprised a substantial...
The southern African Plateau is marked by anomalously high elevations, reaching 1–2 km above sea level, and there much debate as to whether this topography compensated a lower mantle source or elevated temperatures in the upper mantle. In study, we use S-wave receiver functions (SRFs) estimate lithospheric thickness sublithospheric velocity structure beneath Kaapvaal craton, which forms core of Plateau. To fit SRF data, low-velocity zone (LVZ) required below ∼160-km-thick lid, but LVZ no...
As expensive as 3D seismic reflection surveys are, their high cost is justified by improved imaging of certain ore horizons in some the Witwatersrand basin gold mines. The merged historical data acquired for Kloof and South Deep mines forms an integral part Ventersdorp Contact Reef mine planning development programme. recent advances technology have motivated reprocessing reinterpretation old sets using latest algorithms, therefore significantly increasing signal-to-noise ratio data. In...
The lithosphere of Madagascar was initially amalgamated during the Pan-African events in Neoproterozoic. It has subsequently been reshaped by extensional processes associated with separation from Africa and India Jurassic Cretaceous, respectively, subjected to several magmatic late Cretaceous Cenozoic. In this study, crust uppermost mantle have investigated gain insights into present-day structure tectonic evolution Madagascar. We analysed receiver functions, computed data recorded on 37...
ABSTRACT We present an integrated approach to the seismic interpretation of one world's deepest gold ore body (Carbon Leader Reef) using three‐dimensional data, ultrasonic velocity measurements at elevated stresses, and modified instantaneous attribute analysis. Seismic wave velocities drill‐core samples (quartzite, shale, conglomeratic reef) from mine are sensitive uniaxial stress changes, i.e., they slowly increase with increasing pressure until reach maximum value ∼25 MPa. For all...
ABSTRACT Seismic detection of faults, dykes, potholes and iron‐rich ultramafic pegmatitic bodies is great importance to the platinum mining industry, as these structures affect safety efficiency. The application conventional seismic attributes (such instantaneous amplitude, phase frequency) in hard‐rock environment more challenging than soft‐rock settings because geology often complex, reflections disrupted energy strongly scattered. We have developed new that sharpen reflections, enabling...
Abstract Rayleigh wave group and phase velocity measurements obtained from ambient noise earthquake data at 51 broadband stations were used to construct the first 3‐D crustal upper mantle shear model of Botswana. The shows low velocities associated with Passarge Nosop sedimentary basins, whereas Kaapvaal, Zimbabwe, Maltahohe, Congo Cratons are recognized by high velocities. lowest velocity, beneath northeastern Botswana, is southwestern branch East African Rift System. This low‐velocity...