%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Antonio, P. Y. J.
%A Baratoux, Lenka
%A Trindade, R. I. F.
%A Rousse, Sonia
%A Ayite, A.
%A Lana, C.
%A Macouin, M.
%A Adu, E. W. K.
%A Sanchez, C.
%A Silva, M. A. L.
%A Firmin, A. S.
%A Dopico, C. I. M.
%A Proietti, A.
%A Amponsah, P. O.
%A Sakyi, P. A.
%T West Africa in Rodinia : high quality paleomagnetic pole from the similar to 860 Ma Manso dyke swarm (Ghana) [+ corrigendum, 2021, vol. 95, p. 10-13]
%D 2021
%L fdi:010081291
%G ENG
%J Gondwana Research
%@ 1342-937X
%K West Africa ; Neoproterozoic ; Tonian ; Rodinia ; Paleomagnetism
%K GHANA
%M ISI:000643562600002
%P 28-43 [+ corrigendum, 2021, vol. 95,  10-13]
%R 10.1016/j.gr.2021.02.010
%U https://www.documentation.ird.fr/hor/fdi:010081291
%> https://www.documentation.ird.fr/intranet/publi/2021-05/010081291.pdf
%V 94
%W Horizon (IRD)
%X The paleogeography of the Meso-Neoproterozoic Rodinia supercontinent remains debated partly because many stable cratons still lack reliable paleomagnetic data for this period. A new geochronological and paleomagnetic study was conducted on the NNW-trending Manso dyke swarm of southern West Africa (Ghana) to clarify the position of this unconstrained continent in Rodinia. Two U\\Pb apatite ages of 857.2 +/- 8.5 Ma and 855 +/- 16 Ma agree with one previous baddeleyite age, indicating a -860 Ma emplacement age for the Manso dykes. A characteristic remanent magnetization (ChRM) was isolated in stable single to pseudo-single domain (SD-PSD) magnetite. Well constrained site mean directions obtained for 13 dykes lead to a mean direction for the Manso dyke swarm of Dm = 181.9 degrees, Im = -77.2 degrees (N = 13, alpha 95 = 7.6 degrees, k = 30.6), yielding a paleomagnetic pole at 177.6 degrees E, 28.3 degrees S, (A95 = 12.7 degrees K = 11.6). Two directional clusters of opposite inclination passa reversal test (C-class) and the primary origin is supported by a positive baked contact test, satisfying all the seven R-criteria to provide the first West African Tonian key paleomagnetic pole. This key pole indicates a high latitude for the West Africa Craton during the emplacement of the-860 Manso dykes. A compilation of reliable paleomag-netic poles for West Africa, Baltica, Amazonia and Congo-S & atilde;o Francisco cratons suggests that these cratons were together between-1200 and 800 Ma in a long-lived WABAMGO configuration. We suggest that the collision of this block with Laurentia along the Grenvillian-Sunsas orogens closed the external Nuna Ocean and formed Rodinia by extroversion.
%$ 064 ; 066