Major lithospheric thickening is absent and early events such as ophiolites are preserved. It supposes that the vitreous phase of the volcanic tuffs reacts with the free cao caof of portland cement to produce new hydrated minerals. Metallogenic portfolio of the west africa craton deepdyve. The alahina sector is located in the northeast of guinea, precisely in the siguiri volcanosedimentary basin.
Field investigations and kar and 40ar39ar radiometric analysis performed on samples collected from southern guinea provide a new interpretation for metamorphic terranes not yet dated. Metasediments in the alahina sector and associated. In the igherm inlier western antiatlas, morocco dolerilic dyke swarms with various directions and gabbroic intrusive bodies were emplaced during neoproterosoic times, cutting across either eburnean micaschists and granites or panafrican limestones and quartzites. Implication pour levolution pour levolution crustale du paleoproteroique du craton ouestafricain. The present study, essentially based on a structural analysis at outcrop scale. These current two continents have been rotated back to their approximate positions during the triassic period, to show which cratons were joined before the opening of the southern atlantic ocean. Files are available under licenses specified on their description page.
The geophysical signatures of the west african craton. Analysis of rocks in the west african metamorphic province, which is more than 2 gyr old, reveals that some minerals formed. M paris wikipedia citation please see wikipedias template documentation for further citation fields that may be required. Bayer author search for other works by this author on. Feb 22, 2005 read the eglab massif in the west african craton algeria, an original segment of the eburnean orogenic belt. Outline of the panafrican geology of adrar des iforas.
Paleomagnetic contribution to the accretionary phase of rodinia, gondwana research on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Leve gravimetrique du sudouest du craton ouestafricain. Evolution geodynamique du craton ouest africain au nord du ghana. Panafricain i, panafricain ii et hercynien ayant conduit respectivement a ledification des chaines des bassarides, rokelides et mauritanides. Pdf metallogenic portfolio of the west africa craton. The boundaries of the west african craton jeanpaul. Nov 20, 2011 the timing of onset of modernstyle plate tectonics on earth is debated. This page was last edited on 21 january 2017, at 12. An example of the mako and foulde groups kedougou inlier in western senegal. Read archean crustal evolution of the west african craton. Implications geochimiques, these detat es sciences naturelles, univ cheikh anta diop, dakar, senegal, 466 p. Tectonic and magmatic activity was concentrated in mobile belts surrounding the stable areas and took place throughout the late.
The arseniferous pyrites and arsenopyrites of the bagoe belt deposits are among the richest in invisible gold in all gold deposits in west africa and are quite comparable to those of the ashanti belt in ghana. The united nations defines western africa as the 16 countries of benin, burkina faso, cape verde, the gambia, ghana, guinea, guineabissau, ivory coast, liberia, mali, mauritania, niger, nigeria, senegal, sierra leone and togo, as well as the united kingdom overseas territory of saint helena, ascension and tristan da cunha. Senegal suggest new definition this definition appears somewhat frequently and is found in the following acronym finder categories. Ahe analysis was carried out on euhedral inclusionfree apatite. This outcrop was perhaps not insitu and could be a free block.
To achieve these objectives, a geotechnical characterization of the tuff samples was carried out and the geopolymerization stabilization was adopted for the manufacture of bricks. Until now, no satisfactory geodynamic model has been delivered concerning the three main. Implications for the northern limit of the craton, precambrian research on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at. Approximate location of mesoproterozoic older than 1. Read the eglab massif in the west african craton algeria, an original segment of the eburnean orogenic belt. The granitogneissic complex of kan is located in the central part of the paleoproterozoic domain of cote divoire. Contribution to the study of paleoproterozoic materials for. Evolution topographique, tectonique et sedimentaire syn a post. Guinee forestiere forested guinea is a forested mountainous region in southeastern guinea, extending into northeastern sierra leone. Pdf interpretation of satellite magnetic anomalies over. It consists essentially of migmatitic and mylonitic gneisses with basic intrusions and xenoliths. On the ternary keilrankin diagram for the caosio2al2o3 the volcanic tuffs of. The calcalkaline volcanic formations in the western part of the kedougoukenieba inlier crop out in three complexes. The mafic rocks of the lower cryogenian magmatism from the igherm inlier moroccan western antiatlas have calcalkaline.
The data is only saved locally on your computer and never transferred to us. Pdf the geophysical signatures of the west african craton. It is one of four natural regions into which guinea is divided and covers 23% of the country. Jan 10, 2015 the southern guinean terranes belong to the rokelide belt that is located in the southwestern part of the west african craton senegal to liberia. Structures, deformation mechanisms and tectonic phases. The northern fringe of the west african craton is located between the northwest edge of the saharan desert and series of hills of the high atlas in south morocco mainly behind the antiatlas. It consists mainly of metasediments traversed by paleoproterozoic pyroclastite, granite, monzogranite and granodiorite veins as well as mesozoic dolerite and gabbros veins. The west african craton wac is one of the five cratons of the precambrian basement rock of.
The rio del rey delta which represents the part of cameroons margin situated at the north partof the cameroon volcanic line, is the meeting point between three panafrican faults of the benoue. These complexes which either combine with the tholeiites or cut across the sedimentary formations are composed of thin veins and massive lava flows. The full text of this article is available in pdf format. Read paleozoic basins in west africa and the mauritanide thrust belt, journal of african earth sciences on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Petrological and structural approach to understanding the mechanism of formation and development of paleoproterozoic calcalkaline volcanic rocks of west africas craton. In geodynamique du craton ouest africain central et oriental. Despite their altered appearance, the xray diffractions show mineral paragenesis. Comment articuler legislation nationale et droits fonciers. U pb and sm nd evidence for crustal growth and recycling, precambrian research on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at. The pozzolanic reactivity is highlighted by the compressive strength increase until 90 days of conservation in water.
The boad is organised by the central bank of west african states and its eight member governments. The west african craton wac extends across western africa, and consists of two archean nuclei in the northwestern and southwestern parts of the craton juxtaposed against an array of paleoproterozoic domains made up of greenstone belts, sedimentary basins and regions of extensive granitoidttg plutons, which are overlain by neoproterozoic and younger sedimentary basins. Petrological and structural approach to understanding the. The volcanic tuffs of senegaloriental in mako area are produced during a calcalkaline volcanism which occurs in this region and which is dated from about 2. This proterozoic domain belongs to the man leo shield, southern part of west african craton wac. Vertical movements along the northern border of the west. Quartzkaoliniteillite and an important amorphous phase. Archean crustal evolution of the west african craton. Cratons themselves are tectonically inactive, but can occur near active margins, with the wac extending across 14 countries in western african, coming together in the late. West african craton geological region, africa britannica. All structured data from the file and property namespaces is available under the creative commons cc0 license.
Other articles where west african craton is discussed. Interpretation of satellite magnetic anomalies over the west african craton article pdf available in tectonophysics 21212. Le craton ouest africain figure 1 le massif des eglab appartient au craton ouest africain. This study has a positive economic and environmental impact. The west african craton wac is one of the five cratons of the precambrian basement rock of africa that make up the african plate, the others being the kalahari craton, congo craton, saharan metacraton and tanzania craton. These doctorat, universite dorleans, france, 191 p. Le craton ouest africain est ceinture par des chaines mobiles constituees lors des orogeneses panafricaines 800 a 5001lla et hercynienne 300 a 250ma. The objective of this project is the valorization of mako andesitic volcanic tuffs for use in social housing in the kedougou region. Pozzolanic activity of old volcanic tuffs of mako area. The metamorphic evolution of the west african craton. Heritage et evolution postpanafricains eds bitam, l. Lagencement des chaines panafricaines et hercynienne.
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