scholarly journals Corrigendum to ‘Early Neoproterozoic oxygenation dynamics along the northern margin of the West African Craton, Anti-Atlas Mountains, Morocco’ [Chemical Geology 581 (2021) 120404]

2022 ◽  
Vol 590 ◽  
pp. 120703
Author(s):  
Ernest Chi Fru ◽  
Olabode Bankole ◽  
Ibtissam Chraiki ◽  
Nasrrddine Youbi ◽  
Marc-Alban Millet ◽  
...  
2021 ◽  
pp. 120404
Author(s):  
Ernest Chi Fru ◽  
Olabode Bankole ◽  
Ibtissam Chraiki ◽  
Nassrddine Youbi ◽  
Marc-Alban Millet ◽  
...  

2014 ◽  
Vol 255 ◽  
pp. 433-442 ◽  
Author(s):  
J. Javier Álvaro ◽  
André Pouclet ◽  
Hassan Ezzouhairi ◽  
Abderrahmane Soulaimani ◽  
El Hafid Bouougri ◽  
...  

2021 ◽  
pp. jgs2021-034
Author(s):  
Ezzoura Errami ◽  
Ulf Linnemann ◽  
Jamal El Kabouri ◽  
Mandy Hofmann ◽  
Andreas Gärtner ◽  
...  

The comment of Ikenne et al. concerns recently described U-Pb baddeleyite ages, around 1.71 and 1.65 Ga, obtained on intrusive sills and dykes in the Taghdout-Lkest Group in the SW domain of the Anti-Atlas (AA). These authors suggest an independent geodynamic evolution of the eastern and western domains of the Anti-Atlas prior to the Ediacaran period. Furthermore, they state that we do not take this magmatic event into account when interpreting our data. We like to emphasize that this is beyond the scope of our paper and does not affect our interpretation of the AA evolution during the deposition of the Ediacaran sedimentary successions (Saghro, Mgouna, and Ouarzazate goups). We agree with the comment that we did not distinguish the Taghdout-Lkest from the Bleida-Tachdamt groups and now we separate them in the revised figure 2. The different geodynamic evolution of the SW and NE Anti-Atlas domains in pre-Ediacaran times sensu Ikenne et al., is not consistent with abundant inherited Paleoproterozoic zircon detritus and Nd model ages (0.80-1.82 Ga) from the northeastern Anti-Atlas and the Meseta. There is no doubt about Late Paleoproterozoic baddeleyite ages, but they do not have an analogue in the zircon age record of the West African Craton, which is expected from ultramafic rocks with few zircon grains. However, they locally allow assuming a Late Paleoproterozoic deposition of the lower Taghdout-Lkest Group. Any age constraints for the upper parts of this group are lacking, thus allowing a hypothetic deposition between ca. 1.65 Ga and 0.83 Ga (the assumed age of initial Bleida-Tachdamt Group deposition). Therefore, it is very important to close the gap in detailed stratigraphic studies that would allow differentiating between the different Late Paleoproterozoic and Early Neoproterozoic events including the stratigraphic position of the upper Taghdout-Lkest Group and Bleida-Tachdamt group.


1980 ◽  
Vol 17 (4) ◽  
pp. 532-538 ◽  
Author(s):  
Bernard Auvray ◽  
René Charlot ◽  
Philippe Vidal

Orthogneisses from the Tregor area of the North Armorican Massif have been dated using the U/Pb method on zircons. Ages of between 1.8 and 2.0 Ga have been obtained, thus significantly extending the known size of the Lower Proterozoic basement in this area. It is argued that the presence of such a substantial area of basement is a further argument for an Upper Proterozoic (Brioverian) south-dipping subduction zone which was located to the north of the Armorican Massif. On the other hand, the similarities between the North Armorican block and the northern margin of the West African craton during the Proterozoic are emphasized.


2016 ◽  
Vol 06 (08) ◽  
pp. 509-516 ◽  
Author(s):  
Ghalem Zahour ◽  
Hassan El Hadi ◽  
Abdelfatah Tahiri ◽  
Youssef Zerhouni ◽  
Saida Alikouss ◽  
...  

2007 ◽  
Vol 178 (5) ◽  
pp. 343-352 ◽  
Author(s):  
Youssef Raddi ◽  
Lahssen Baidder ◽  
Mohamed Tahiri ◽  
André Michard

Abstract North of the Saharan cratonic domain, the Anti-Atlas mountains correspond to the foreland, external fold belt of the Variscan orogen which extends in the Meseta block to the north, and Mauritanides to the southwest. The Anti-Atlas was uplifted during the Mesozoic-Cenozoic, and display several basement culminations (“boutonnières”) amidst the folded Palaeozoic cover. Recent studies in western Anti-Atlas emphasized the basement implication in the shortening process (thick skinned structure). Hereafter we investigate the cover-basement relations in eastern Anti-Atlas south of the Ougnat culmination, based on mapping at scale 1:50,000. The Palaeozoic sequence is much thinner than in the west, and the décollement levels are less important. Flexural slip folds are concentrated along the faults (en échelon folds) and within some rhombic domains crushed between major faults (e.g. Angal-Gherghiz Lozenge), whereas other areas are monoclinal. The main shortening direction deduced from the fold axes trend is directed ~N045°E as in the Ougarta range further to SE. At a regional scale, this shortening direction interferes with a N-S trending one. A sketch map of the top of the basement makes visible a mosaic of S- to SE-ward tilted blocks. The faults between these blocks are inherited from paleofaults which formed during extensional events during the Cambrian, late Ordovician, and (mainly) Middle-Late Devonian. The paleofault array is indicative of a proximal passive margin setting at the northern border of the metacratonic domain. The fault inversion and their dominant strike-slip throw occurred during a late Variscan (Stephanian-Permian) compression event, postdating the NNW-SSE collision of the Meseta block.


1980 ◽  
Vol 17 (1) ◽  
pp. 142-155 ◽  
Author(s):  
M. Leblanc ◽  
J. R. Lancelot

U–Pb and Rb–Sr ages performed in the Anti-Atlas (Morocco), especially in Bou Azzer area, demonstrate a Pan-African orogeny (680–570 Ma), along the northern margin of the West African craton (2000 Ma). Geological and geochronological data allow the reconstitution of a coherent succession of events of Pan-African ages. The geodynamic evolution of this domain comprises a stage of oceanic opening (ophiolites) followed with a stage of closure: obduction of the ophiolites on the craton, then subduction under an active continental margin. This segment of the Pan-African belt can be correlated with the other parts of the belt, located on the eastern margin of the West African craton.


2008 ◽  
Vol 297 (1) ◽  
pp. 329-343 ◽  
Author(s):  
H. Ezzouhairi ◽  
M. L. Ribeiro ◽  
N. Ait Ayad ◽  
M. E. Moreira ◽  
A. Charif ◽  
...  

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