Melt infiltration of the lower lithosphere beneath the. Formation and evolution of archaean cratons geological society. The namaqua belt is the southern margin of the kaapvaal craton. Kalahari limited free company information from companies house including registered office address, filing history, accounts, annual return, officers, charges, business activity. With the exception of the damara belt that separates the congo and kalahari cratons, any highspeed uppermantle lid below the panafrican terranes is too thin. Around ma, a syntectonic trondhjemitic pluton intruded into the archaean reelects of the chegga series. These current two continents have been rotated back to their approximate positions during the. Most of the rocks of the kalahari craton have archaean 38002500 ma or. African upper mantle and its relationship to tectonics and. The evolution of lithospheric mantle beneath the kalahari. The kalahari craton consists of three major crustal domains, the kaapvaal craton to the south, the. The greater kalahari craton is composed of the archean kaapvaal figure 1a and zimbabwe figure 1b cratons sutured together by the. The kaapvaal province of the archean kalahari craton differs from other african archean terrains by its early cratonization, representing a nearly 1 mill.
Pdf the kalahari craton during the assembly and dispersal of. Palaeomagnetic constraints on the position of the kalahari. While flying aerial reconnaissance during this period, mark spotted one of the largest. A comparative provenance study of the late mesoproterozoic. This is a list of tectonic plates on the earths surface. Kalahari craton and 225 km beneath the congo craton, respectively.
Tectonic plates are pieces of earths crust and uppermost mantle, together referred to as the lithosphere. Nevertheless, from isolated outcrops, boreholes and geophysical evidence it is known that the zkg craton is juxtaposed against palaeoproterozoic rocks of the kheis, okwa and magondi sequences singletary et al. During the late stages of gondwana amalgamation, the congo craton collided with the kalahari craton to form central gondwana, generating tectonometamorphic overprints that are displayed in the rocks of. Forfurther discussion of this issue see also hofmann et al. By the eocene, in the cenozoic, the region returned to terrestrial conditions. These contemporaneous magmatic events occurred while the rodinia supercontinent was being assembled and are inferred to be. The orthogneisses form part of an extensive region north of the kalahari craton and east of the congo craton that includes large amounts of 1. We show that intraplate magmatism occurred 1106 to 1112 million years ago over an area of two million square kilometers within the kalahari craton of southern africa, during the same magnetic polarity chron as voluminous magmatism within the cratonic core of north america. Pdf archean accretion and crustal evolution of the. The congo craton, covered by the palaeozoictorecent congo basin, is an ancient. Archean accretion and crustal evolution of the kalahari craton the zircon age and hf isotope record of granitic rocks from barbertonswaziland to the francistown arc. The area is underlain by palaeozoicmesozoic sedimentary rocks called the karroo complex.
This is a retouched picture, which means that it has been digitally altered from its original version. The kalahari craton consists of three major crustal domains, the kaapvaal craton to the south, the zimbabwe craton to the north and the limpopo belt between them. This implies different conditions in the source terrains of the two. Introduction the position of the kalahari craton within rodinia is still actively debated and two contrasting palaeogeographic models have recently. Simplified geological map showing the northern part of the kaapvaal craton modified from johnson. Forfurther discussion of this issue see also hofmann et. If you would like to participate, you can choose to. The reso lution tests indicate that both laterally and vertically the cratonic. Sedimentological and stratigraphic analyses of the otavi. This major collision orogen included the belts of southern africa and east antarctica the outer rim of the kalahari craton. Also, the trilobite and, especially, primitive molluscan faunas of the cambrian strata of the ellsworths bear resemblance to those of. The western craton margin coincides with the linear.
We present a new grand mean palaeomagnetic pole plong. The kaapval craton is limited to the north by the limpopo mobile belt 1, which was formed by a series of tectonic, magmatic and metamorphic events. The kalahari was hit hard by the african drought of the late 70s and early 80s and dried into miles of dusty badlands. Craton, africa the palaeoproterozoic evolution of the. Comparable to the nasca lines in size, and even more impressive in intricacy, a.
The african upper mantle and its relationship to tectonics and. The kalahari craton is a craton, an old and stable part of the continental lithosphere, that. Kalahari craton from australiamawsonland according to evans, 2009, pisarevskyetal. Congo craton incorporated primarily juvenile crust whereas the kalahari craton incorporated primarily recycled crust during this time. Latetectonic copper emplacement in a damaran imbricate shear system shawn kitt, stellenbosch university, south africa ken maiden, international base metals. The kalahari craton during the assembly and dispersal of rodinia pdf. Description survivor meets james bond in this pageturning mix of realism and science fiction. These data, although valuable, allow only a limited interpretation of the crustmantle evolution both in space and time, and cannot help in answering a number of other important. Kalahari limited overview free company information from. Direct mesoproterozoic connection of the congo and kalahari. The western and northern margins of the archaean nucleus are extremely poorly exposed under younger cover rocks of the kalahari desert. Upper mantle p and s wave velocity structure of the kalahari. We therefore invoke initial underthrusting of the kalahari craton below the congo craton during the collision of these two cratons, leading to mantle lithosphere eclogitization and delamination, and.
The kalahari craton is a craton, an old and stable part of the continental lithosphere, that occupies large portions of south africa, botswana, namibia and zimbabwe. A great deal of geological and geophysical work has been published on the kalahari craton of southern africa, but relatively little is known about the other cratons. Nevertheless, from isolated outcrops, boreholes and geophysical. The amazonian craton major accretionary and collisional processes may be correlated to supercontinent assemblies developed at several times in the earth history. Finding and building worldclass mines on different. Read palaeomagnetic constraints on the position of the kalahari craton in rodinia, precambrian research on deepdyve, the largest online rental service for scholarly research with. In southern africa, for example, the kalahari craton in sl20 is generally where we see it now but it is smoother and broader. Upb geochronology of the tsineng dyke swarm and paleomagnetism of the hartley basalt formation, south africa evidence for two separate magmatic events at 1. Archean accretion and crustal evolution of the kalahari. Modeling of craton stability using a viscoelastic rheology. Panafrican belts along the northern and eastern craton margins are associated in one area with a 1.
Openfile report 20071047, extended abstract 090, 4 p. Namaquanatal province, which led to the formation of the kalahari craton. Simplified geological map of the kalahari craton of southern africa showing the location of the kaapvaal. Fannual information form on file with the sec and canadian provincial securities regulatory authorities for a more detailed discussion of some of the factors underlying forwardlooking statements and the. This sea closed by 550 million years ago, and these continental masses collided to form the great southern. The history of botswanas major seismic events has been initiated by two earthquakes that occurred on the 11th of september and 11th of october 1952 with ml richter magnitudes of 6. Inspire a love of reading with prime book box for kids discover delightful childrens books with prime book box, a subscription that. The palaeoposition and growth from the zimbabwekaapvaalgrunehogna craton to greater kalahari between ca.
The kalahari craton during the assembly and dispersal of. Crustal recycling in the damara belt, namibia, and. According to their tomographic study the tanzania craton extends down to 180. It consists of two cratons separated by the limpopo belt. Formation of the archean kaapvaal province revisited. Precambrian crustal evolution of the rehoboth province. Zircon upb, hf and oisotopic results from granites and basement rocks from the southwestern central zone of the damara belt namibia are used to decipher the process of remobilization during collision. The compositional structure and thermal state of the subcontinental lithospheric mantle sclm beneath the kalahari craton and the surrounding mobile belts have been mapped in space and time using. Kalahari craton geological region, africa britannica. Within botswana, outcrop of geological units correlated with the kaapvaal craton e. Approximate location of mesoproterozoic older than 1.
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