The CONGO CRATON, covered by the
Congo Basin ,
is an ancient
Precambrian craton that with four others (the Kaapvaal ,
Zimbabwe , Tanzania , and West African cratons) makes up the modern
Craton occupies a large part of central southern Africa,
extending from the Kasai region of the DRC into
* 1 Congo–São Francisco
* 1.1 West Congo Belt
* 2 See also
* 3 References
* 3.1 Notes * 3.2 Sources
The Congo Craton and the São Francisco Craton are stable Archaean blocks that formed a coherent landmass until the opening of the South Atlantic Ocean during the break-up of Gondwana (c. 2000–130 Ma). They stabilised during the Trans-Amazonian orogeny and Eburnian orogeny and have been affected by a long series of orogens since resulting in similar sequences on both blocks.
Congo–São Francisco experienced three large igneous province (LIP)
events at 1380–1370 Ma, c. 1505 Ma, and c. 1110 Ma. The relative
position of Congo–São Francisco within the supercontinent
Nuna/Columbia can be reconstructed because these LIP events also
Precambrian continental blocks. Within Nuna the
northern part of Siberia was located adjacent to western São
Francisco. 1110 Ma dyke swarms in
It is possible that the 1110 Ma LIP in Congo–São Francisco,
Amazonia, and India was part of a much larger event that also involved
At the time for the formation of the supercontinent Gondwana at c. 550 Ma the Congo Craton formed the already amalgamated central African landmass. The southern and eastern margins (modern coordinates) of this landmass was made of the Archaean Angola-Kasai block and Tanzanian Craton. These proto-Congo blocks were deformed in the Palaeoproterozoic Eburnean orogeny but later stabilised.
WEST CONGO BELT
Before the opening of the South Atlantic the São Francisco and Congo cratons were connected by a "cratonic" bridge, the Bahia–Gabon Bridge. The most recent orogenic event on this bridge occurred at 2 Ga, so the connection between São Francisco and Congo must have formed during the Palaeoproterozoic. South of this cratonic bridge the Araçuaí–West Congo orogen evolved in the Neoproterozoic in a sea basin made of oceanic crust, an embayment in the São Francisco–Congo continent.
The West Congo Pan-African Belt includes major magmatic events at c. 1000 and 910 Ma. In the Early Neoproterozoic, the western edge of Congo Craton was the location for the initial rifting of Rodinia before its break-up. During the Neoproterozoic, Central Congo or Bas-Congo became a passive margin on which was deposited 4,000 m (13,000 ft) sediments. At the end of the Neoproterozoic, Bas-Congo was only affected by the Pan-African orogeny at 566 Ma to a limited extent protected by this passive margin and by the thickness of the craton. At 1000 Ma peralkaline magmatism initiated an early transtensional setting along the western edge of the Congo Craton. An LIP at c. 930–920 Ma was followed by felsic magmatism between c. 920–910 Ma which had a short emplacement interval and resulted in a 3,000–4,000 m (9,800–13,100 ft) thick sequence. Mafic-felsic magma sequences (6,000 m (20,000 ft) thick) on the western edge of the Congo Craton are similar to those of the Paraná and Deccan LIPs, but in the Congo Craton the magma source became shallower with time. There was no geodynamic activity along the western Congo margin during the Mesoproterozoic.
* ^ Ernst et al. 2013 , Conclusions, p. 116
* ^ Pedreira & De Waele 2008 , p. 33–34
* ^ Ernst et al. 2013 , Abstract
* ^ Pisarevsky et al. 2014 , Congo/ São Francisco and Siberia
* ^ de Kock et al. 2014 , Other 1.1 Ga LIPs?, pp. 139–140
* ^ De Waele, Johnson Pedrosa-Soares, A. C.; Trindade, R. I. F. D.;
Martins, M.; Noce, C. M.; Liu, D. (2012). "Neoproterozoic glacial
deposits from the Araçuaí orogen, Brazil: Age, provenance and
correlations with the São Francisco craton and West Congo belt"
Gondwana Research_. 21 (2): 451–465. doi
:10.1016/j.gr.2011.04.008 . Retrieved 7 May 2017.
* de Kock, M. O.; Ernst, R.; Söderlund, U.; Jourdan, F.; Hofmann,
A.; Le Gall, B.; Bertrand, H.; Chisonga, B. C.; Beukes, N.; Rajesh, H.
M.; Moseki, L. M.; Fuchs, R. (2014). "Dykes of the 1.11 Ga Umkondo
LIP, Southern Africa: Clues to a complex plumbing system" (PDF).
Precambrian Research_. 249: 129–143. doi
:10.1016/j.precamres.2014.05.006 . Retrieved 6 May 2017.
* De Waele, B.; Johnson, S. P.; Pisarevsky, S. A. (2008).
Palaeoproterozoic to Neoproterozoic growth and evolution of the
eastern Congo Craton: its role in the
Rodinia puzzle" (PDF).
Precambrian Research_. 160 (1): 127–141. Retrieved 6 May 2017.
* Ernst, R. E.; Pereira, E.; Hamilton, M. A.; Pisarevsky, S. A.;
Rodriques, J.; Tassinari, C. C.; Teixeira, W.; Van-Dunem, V. (2013).
Mesoproterozoic intraplate magmatic ‘barcode’record of the Angola
portion of the Congo Craton: Newly dated magmatic events at 1505 and
1110Ma and implications for Nuna (Columbia) supercontinent
reconstructions" (PDF). _
Precambrian Research_. 230: 103–118.
Retrieved 6 April 2017.
* Pisarevsky, S. A.; Elming, S. Å.; Pesonen, L. J.; Li, Z. X.
Mesoproterozoic paleogeography: supercontinent and beyond"
Precambrian Research_. 244: 207–225. doi
:10.1016/j.precamres.2013.05.014 . Retrieved 6 May 2017.
* Pedreira, A. J.; De Waele, B. (2008). "Contemporaneous evolution
of the Palaeoproterozoic–
Mesoproterozoic sedimentary basins of the
São Francisco–Congo Craton" (PDF). _Geological Society, London,
* v * t * e
Major African geological formations
CRATONS AND SHIELDS
* Alpide Orogen * Cape Fold Belt * Damara Orogen * East African Orogen * Eburnean Orogen * Gondwanide Orogen * Kibaran Orogen * Kuunga Orogen * Mauritanide Belt * Pan-African orogens * Terra Australis Orogen
* Blue Mountains
* v * t * e
Continents of the world
* HISTORICAL CONTINENTS
* _See also Regions of the world _ * _ Continental fragment _
* BOOK * CATEGORY
Links: ------ /wiki/Palaeozoic /wiki/Congo_Basin /wiki/Precambrian /wiki/Craton