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Geology Of The Central African Republic
The geology of Central African Republic (CAR) is part of the broader geology of Africa. CAR occupies a swath of ancient rocks, dating back billions of years that record significant aspects of Earth history and yield minerals vital to the country's small economy. Geologic history Southern CAR is part of the Congo Craton, a stable landmass dating to the Archean that was once fused with the Sao Francisco Craton until the opening of the South Atlantic Ocean. Some of the oldest rocks in CAR belong to the 3.4 billion year old Bomu Complex which includes migmatite gneiss and metasedimentary schist spanning from the Democratic Republic of Congo. The Congo Craton once functioned as a small continent, until it was joined with Siberia during the formation of the supercontinent Columbia, between 2.1 and 1.8 billion years ago. A string of large igneous province (LIP) volcanic events took place in three pulses during the time that the craton was part of Columbia, until the supercontinent fragmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central African Republic
The Central African Republic (CAR; ; , RCA; , or , ) is a landlocked country in Central Africa. It is bordered by Chad to the north, Sudan to the northeast, South Sudan to the southeast, the DR Congo to the south, the Republic of the Congo to the southwest, and Cameroon to the west. The Central African Republic covers a land area of about . , it had an estimated population of around million. , the Central African Republic is the scene of a civil war, ongoing since 2012. Most of the Central African Republic consists of Sudano-Guinean savannas, but the country also includes a Sahelo- Sudanian zone in the north and an equatorial forest zone in the south. Two-thirds of the country is within the Ubangi River basin (which flows into the Congo), while the remaining third lies in the basin of the Chari, which flows into Lake Chad. What is today the Central African Republic has been inhabited for millennia; however, the country's current borders were established by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bakouma Formation
Bakouma is a sub-prefecture in the prefecture of Mbomou in Central African Republic. The area is known for its prosperity of mineral resources which have for a long time remained unexploited. History Bakouma was founded in September 1892 when the Belgians, led by Commander Georges Adolphe Balat and Captain Georges Le Marinel set up a military post on the site. It became a part of the French Upper Oubangui in July 1894. Bakouma became a district under the French rule in 1944 and on 23 January 1961, the region eventually became a Sous-Préfecture in the Mboumo prefecture in the newly formed Central African Republic. . The Lengo Petroglyphs are located near Bakouma. In a uranium survey in 1959–1961, phosphatic sediments were discovered near Bakouma. The phosphates are characterized by their high uranium content, which are the highest in sub-Saharan Africa. Further feasibility studies showed that in the area, there are 41 million pounds of U3O8 with an average grade of 0.27% (whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greenstone Belt
Greenstone belts are zones of variably metamorphosed mafic to ultramafic volcanic sequences with associated sedimentary rocks that occur within Archaean and Proterozoic cratons between granite and gneiss bodies. The name comes from the green hue imparted by the colour of the metamorphic minerals within the mafic rocks: the typical green minerals are chlorite, actinolite, and other green amphiboles. Greenstone belts also often contain ore deposits of gold, silver, copper, zinc and lead. A greenstone belt is typically several dozens to several thousand kilometres long. Typically, a greenstone belt within the greater volume of otherwise homogeneous granite-gneiss within a craton contains a significantly larger degree of heterogeneity and complications and forms a tectonic marker far more distinct than the much more voluminous and homogeneous granites. Additionally, a greenstone belt contains far more information on tectonic and metamorphic events, deformations, and paleogeologic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dekoa Belt
Dekoa (Dékoua) is a sub-prefecture and town in the Kémo Prefecture of the south-eastern Central African Republic. History In the nineteenth century freebooter Rabih az-Zubayr brought Dekoa under his sway and made it a part of the Bornu Empire. In March 1899, the sultan captured and imprisoned the explorer Ferdinand de Béhagle at Dekoa. Béhagle was subsequently hanged after the French battled the sultan's troops at Kouno in October of that year. Civil war On 28 December 2012 Séléka rebels took control of Dekoa. On 8 April 2014 Anti-balaka attacked ex-Seleka positions in Dekoa resulting in 30 deaths. On 17 August 2018 FACA was deployed in Dekoa. Three UN peacekeepers from Burundi were killed in Dekoa and Bakouma on December 26, 2020, one day before the 2020 Central African general election. Three Anti-balaka leaders in Kaga-Bandoro Kaga-Bandoro is a market town and capital of the Nana-Grébizi prefecture of the Central African Republic. It represents the seat of the Rom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gneiss
Gneiss ( ) is a common and widely distributed type of metamorphic rock. It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks. Gneiss forms at higher temperatures and pressures than schist. Gneiss nearly always shows a banded texture characterized by alternating darker and lighter colored bands and without a distinct cleavage. Gneisses are common in the ancient crust of continental shields. Some of the oldest rocks on Earth are gneisses, such as the Acasta Gneiss. Description Orthogneiss from the Czech Republic In traditional English and North American usage, a gneiss is a coarse-grained metamorphic rock showing compositional banding (gneissic banding) but poorly developed schistosity and indistinct cleavage. In other words, it is a metamorphic rock composed of mineral grains easily seen with the unaided eye, which form obvious compositional layers, but which has only a weak tendency to fracture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphibolite
Amphibolite () is a metamorphic rock that contains amphibole, especially hornblende and actinolite, as well as plagioclase feldspar, but with little or no quartz. It is typically dark-colored and dense, with a weakly foliated or schistose (flaky) structure. The small flakes of black and white in the rock often give it a salt-and-pepper appearance. Amphibolite frequently forms by metamorphism of mafic igneous rocks, such as basalt. However, because metamorphism creates minerals entirely based upon the chemistry of the protolith, certain 'dirty marls' and volcanic sediments may also metamorphose to an amphibolite assemblage. Deposits containing dolomite and siderite also readily yield amphibolite (tremolite-schist, grunerite-schist, and others) especially where there has been a certain amount of contact metamorphism by adjacent granitic masses. Metamorphosed basalt (metabasalt) creates ''ortho-amphibolite'' and other chemically appropriate lithologies create ''para-amphibolite''. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tillite
image:Geschiebemergel.JPG, Closeup of glacial till. Note that the larger grains (pebbles and gravel) in the till are completely surrounded by the matrix of finer material (silt and sand), and this characteristic, known as ''matrix support'', is diagnostic of till. image:Glacial till exposed in roadcut-750px.jpg, Glacial till with tufts of grass Till or glacial till is unsorted glacier, glacial sediment. Till is derived from the erosion and entrainment of material by the moving ice of a glacier. It is deposited some distance down-ice to form terminal, lateral, medial and ground moraines. Till is classified into primary deposits, laid down directly by glaciers, and secondary deposits, reworked by fluvial transport and other processes. Description Till is a form of ''glacial drift'', which is rock material transported by a glacier and deposited directly from the ice or from running water emerging from the ice. It is distinguished from other forms of drift in that it is deposi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
