A craton is a large, stable portion of earths lithosphere. Kaap vaal trust, its agents, employees, contractors and subcontractors will not be liable for any loss or damage arising directly or indirectly from the. The kaapvaal craton centred on limpopo province in south africa, along with the pilbara craton of western australia, are the only remaining areas of pristine 3. You may do so in any reasonable manner, but not in.
Paleomagnetism of selected neoarcheanpaleoproterozoic. Pdf crustal structure and tectonic evolution of the. It also hosts the largest platinum group element pge deposits e. The early archaean nondweni greenstone belt, southern kaapvaal. Start this article has been rated as startclass on the projects quality scale. Jelsma encyclopedia of life support systems eolss 2. The lithospheric mantle beneath the kaapvaal zimbabwe craton of southern africa shows variations in seismic pwave velocity at depths within the diamond stability field that correlate with differences in the composition of diamonds and their syngenetic inclusions. The paleoarchean pilbara craton, western australia. Given the established nature of geoscientific knowledge of the kaapvaal craton compared to the slave craton, and given the exciting new interdisciplinary results coming from the kaapvaal project and from. Zimbabwe craton to the north and the kaapvaal craton to the south. Files are available under licenses specified on their description page.
The seismometers were deployed at locations across southern africa from april 1997 through april 1999, with about fifty stations operating at any one time fig. Kaapvaal cratons, which amalgamated along the limpopo province e. The gold and rounded pyrites from the conglomerates yield a rheniumosmium isochron age of 3. The lithospheric mantle beneath the kaapvaalzimbabwe craton of southern africa shows variations in seismic pwave velocity at depths within the diamond stability field that correlate with differences in the composition of diamonds and their syngenetic inclusions. Paleomagnetism of selected neoarcheanpaleoproterozoic cover. The main building blocks of the kaapvaal craton and the age distribution of exposed basement and supracrustal rocks after eglington and armstrong 2004 with tectonic interpretations after jacobs et al. Overnight at river view lodge in prieska bb 20 aug 16 satur day windpomp and nouga farms drive to nouga farm, c.
The kaapvaal craton in south africa is, along with the pilbara craton of western australia, the only areas where midarchean 3. This absence of a consistent geodynamic framework within which regionalscale observations can be placed limits our understanding of archaean assemblages and. This allows the spatial extension of the different volcanic stratigraphic units to be interpreted. Here we show that olivine in peridotite xenoliths from the lithosphereasthenosphere boundary region of the kaapvaal craton mantle root are waterpoor and provide sufficient viscosity contrast. The following are the supplementary data to this article. Formation and evolution of archaean cratons home geological. Pdf formation of the archean kaapvaal craton revisited. Crustal structure and tectonic evolution of the kaapvaal craton. This book provides a comprehensive overview of the evolution of one of the oldest and best exposed archaean cratons on this planet, features information on.
A reos isotope study of peridotite xenoliths from lesotho kimberlites. With the exception of the northern margin, the boundaries of the province are well defined. Kaap vaal trust may amend sections and add, replace, or remove forms or documents without notice. The archean kaapvaal and zimbabwe cratons form the continental nucleus of southern africa. The joint inversion of rayleigh wave group velocities and body wave receiver functions is used to constrain the shear wave velocity structure across the kaapvaal craton and surrounding mobile belts. The kaapvaal craton is one of the best preserved of all archean cratons. These include the rocks of the zimbabwe craton and. A pdf file listing the public data used in this compilation and the. Of 22 silicate and oxidebearing diamondites investigated, most yielded garnet intergrowths n 15 with. The origin of the kheis terrane and its relationship with. Unconformity above ventersdorp rocks, basal conglomerates, transition to quartzites, beach and aeolian deposits, transition to carbonates.
It was formed when when the earths basaltic crust was intruded by granite. Gold on the kaapvaal craton, outside the witwatersrand. Characteristics of the volcanic rocks and constraints on magma. Understanding earth by grotzinger pdf free download. He has published more than 400 scientific papers and was editor or was on the editorial board of several international earth science journals. Data for the precambrian of south africa, swaziland, lesotho and botswana have been compiled in a dateview database and linked to chronostratigraphy and gis databases to produce a series of timeslice maps illustrating the development of the kaapvaal craton. The reso lution tests indicate that both laterally and vertically the cratonic. Most of the detrital zircon grains incorporated into the keis supergroup were derived from the magondi and limpopo belts and the zimbabwe craton to the. The kaapvaal craton most probably never acted as a major source area for the rocks of the keis supergroup because of the lack of paleo to mesoarchean zircon populations in the keis supergroup. Outside of the witwatersrand basin significant quantities of gold have been recovered from archaean greenstone belts of the 3500 to 2700 ma kaapvaal craton as well as from various occurrences in the 2600 to 2200 ma transvaal supergroup. A tale of two pandas download ebook pdf, epub, tuebl, mobi. The bushveld complex, the outcrop limbs of which are shown in fig. The timing of the palaeoproterozoic great oxidation event.
In this study, the lithospheric strength of the kaapvaal craton is determined using deformation laws describing the failure of rocks at lithospheric depths. If you would like to participate, you can choose to edit this article, or visit the project page for more information. This file is licensed under the creative commons attributionshare alike 3. Structure of the kaapvaal craton from surface waves. The report then discusses the basin geology in zimbabwe. Download limit exceeded you have exceeded your daily download allowance.
Nguuri bernard price institute of geophysical research, school of geosciences, university of the witwatersrand, private bag 3, wits 2050, south africa. It consists of two cratons separated by the limpopo belt. Crustal structure of the kaapvaal craton and its significance. Evolution of the kaapvaal craton as viewed from geochemical and. Kaap vaal trust takes reasonable steps to ensure that the information contained on this website is accurate and up to date. P wavespeed structure below and around the kaapvaal craton to. Formation of the archean kaapvaal province revisited. The kaapvaal craton itself is comprised of an eastern domain with age ca.
The archaean geology of the kaapvaal craton, southern africa. Pdf lithospheric mantle evolution of the kaapvaal craton. Jun 12, 2008 the kaapvaal craton subsequently collided with the zimbabwe craton some 2. Granite can be seen in the valley between melmoth and vryheid, and at quarries. Liquidators insolvency practitioners kaap vaal trust. Structural history of the southwestern corner of the kaapvaal craton. This site is like a library, use search box in the widget to get ebook that you want. The archaean geology of the kaapvaal craton southern africa book summary.
A map of kaapvaal craton based on map of kaapvaal craton. Shear wave velocity results from a previous study were used to constrain the rheological profiles associated with each of the 64 broadband seismic stations deployed across the craton. Visualizing the volcanic history of the kaapvaal craton using. The kaapvaal craton and adjacent orogens, southern. Geochemistry of palaeoarchaean to palaeoproterozoic kaapvaal. Kaapvaal craton geological region, africa britannica. A thermotectonic framework for the growth and stabilization of the eastern kaapvaal craton, southern africa. Jul 17, 2018 in this study, the lithospheric strength of the kaapvaal craton is determined using deformation laws describing the failure of rocks at lithospheric depths. These and similar, but rightlateral faults are the last movements along the rim of the craton and occurred around 1. Kaapvaal craton and limpopo belt and their cover successions until the formation of.
Variations in the thickness of the crust of the kaapvaal. There is currently a renewed interest in the early earth, and the kaapvaal craton has. A craton is a large, stable portion of earths lithosphere that makes up part of a continent. Diamond genesis, seismic structure, and evolution of the. Earth planets space, 56, 1257, 2004 variations in the thickness of the crust of the kaapvaal craton, and mantle structure below southern africa c. Structure of the kaapvaal craton from surface waves structure of the kaapvaal craton from surface waves freybourger, marion. Developments in precambrian geology earths oldest rocks. Very little gold has been found in younger formations. The pendotites from the kaapvaal craton are mostly garnetbearing xenoliths in kmberlite 1,11,38,5462,88. P wavespeed structure below and around the kaapvaal craton.
The physical manifestations of plate tectonics on the modern earth are relatively wellunderstood, but the nature and timing of its onset remains enigmatic, with the geodynamic regimes that operated during the archaean hotly debated. Bushveld igneous complex which mining companies have exploited in different mineralised layered magmatic zones. Geochronological comparisons of large datasets are facilitated by the use of structured databases. The paleopoles established here, together with existing paleopoles from the kaapvaal craton, are used to evaluate the apparent polar wander path of the craton during the neoarcheanpaleoproterozoic and are compared with poles of similar age from the pilbara craton as a test of the vaalbara hypothesis. Gold on the kaapvaal craton, outside the witwatersrand basin. Jelsma encyclopedia of life support systems eolss the worldwide 1. Garnet lherzolites from the kaapvaal craton south africa. Witwatersrand supergroup which mining companies have exploited at certain stratigraphic positions. Roering 1992a geologic observations across a tectonometamorphic boundary in the babangu area, giyani sutherland greenstone belt, south africaprecambrian res. These form separate continental blocks that have influenced the geological history, scenery and economic potential of the region. Pdf archaean crystalline rocks of the eastern kaapvaal craton. Precambrian cratonic pelites from the kaapvaal craton in southern africa have similar ree patterns with relative lree enrichment and absence of significant. The early archaean nondweni greenstone belt, southern kaapvaal craton, south africa, part ii. The kaap vaal craton itself is comprised of an eastern domain with.
The kaapvaal craton formed and stabilised between 3. We calculated the seismic properties of 47 mantle xenoliths from 9 kimberlitic pipes in the kaapvaal craton based on their modal composition, the crystalpreferred orientations cpo of olivine, ortho and clinopyroxene, and garnet, the fe content of olivine, and the pressures and temperatures at which the rocks were equilibrated. The kaapvaal craton and adjacent orogens, southern africa. This suite of high grade metamorphic rocks dominates the limpopo basin. Download acrobat pdf file 2mb supplementary figs s1 to s4. Understanding earth by grotzinger pdf free download ebook. The kaapvaal network consisted of approximately eighty broadband stations that formed part of the international kaapvaal craton programme carlson et al.
It is partially covered by the supracrustal sequences of the witwatersrand, ventersdorp and transvaal basin and correlated griqualand west basin, which span almost a billion years 3. Kaapvaalslave craton workshop, at merrickville, ontario, canada, volume. Middle archean mantle depletion events initiated craton keel formation and early harzburgitic diamond formation. The kaapvaal craton subsequently collided with the zimbabwe craton some 2. Craton, the stable interior portion of a continent characteristically composed of ancient crystalline basement rock. The term craton is used to distinguish such regions from mobile geosynclinal troughs, which are linear belts of sediment accumulations subject to subsidence i. The kaapvaal craton is one of the very few remaining areas of pristine crust on earth. The petrogenesis and relationship of diamondite to wellstudied monocrystalline and fibrous diamonds are poorly understood yet would potentially reveal new aspects of how diamondforming fluids are transported through the lithosphere and equilibrate with surrounding silicates. The rock has remained tectonically stable since its formation 3. The kaapvaal craton in africa is one of five ancient cratons left from the precambrian era.
Lithospheric mantle evolution of the kaapvaal craton. Thus, the gold is detrital and was not deposited by. The archaean geology of the kaapvaal craton, southern. Feb 10, 2020 craton plural cratons a part of the earths crust that has survived the splitting and merging of continents. The extensive central cratons of continents may consist of both shields and platforms. All structured data from the file and property namespaces is available under the creative commons cc0 license.
Olivine water contents in the continental lithosphere and the. This book provides a comprehensive overview of the evolution of one of the oldest and bestexposed archaean cratons on this planet. The kalahari craton during the assembly and dispersal of rodinia pdf. While stabilization of the kaapvaal craton was essentially complete by about 2. This page was last edited on 25 september 2019, at 00. The kaapvaal province of the archean kalahari craton differs from other african archean terrains by its early cratonization, representing a nearly 1 mill. Introduction the archaean kaapvaal craton and adjacent proterozoic mobile belts cover much of southern africa fig. The kalahari craton during the assembly and dispersal of.
Olivine water contents in the continental lithosphere and. Visualizing the volcanic history of the kaapvaal craton. Similarities of rock records from both these cratons, especially of the overlying late archean sequences, suggest that they were once part of the vaalbara supercontinent. The kaapvaal craton hosts a number of large gold deposits e. He is a field geologist with interest in tectonics and geochronology and has mainly worked on aspects of crustal evolution in africa, specifically the kaapvaal craton of southern africa. Sloss editor, sedimentary covernorth american craton. Origin and geodynamic significance of ultramaficmafic. A feasibility study on the use of mine tremors in south africa for determining crustal structure was pioneered more than. Continental mantle signature of bushveld magmas and coeval. Gondwanaland, kaapvaal craton, crust and mantle structure. The basalts are 3500 million years old and are preserved as greenstone fragments within the granit.
Stratigraphic and structural interpretation of seismic. There is currently a renewed interest in the early earth, and the kaapvaal craton has long served as a model for early crustal evolution. The geological evolution of africa encyclopedia of life. To the north, the craton is bounded by the limpopo belt, which separates it from the zimbabwe craton.
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