| Titre | Introduction | |
|---|---|---|
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Revue | Bulletin de l'Association de Géographes Français |
| Numéro | no 489-490, 1982 | |
| Rubrique / Thématique | Séance du 6 novembre 1982 Séance sur les bourrelets marginaux (The marginal bulges of the old shields) Thème 2 : Les bourrelets intertropicaux (The intertropical bulges) |
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| Page | 261 | |
| Résumé |
Résumé. - Cette seconde partie passe en revue les bourrelets du SW et du SE africain, de la façade orientale de Madagascar, et de la péninsule indienne. Source : Éditeur (via Persée) |
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| Résumé anglais |
Abstract. - From Namibie to Congo, the western african bulge was first uplifted before the Aptian. But major flexuration was emplaced between upper Cretaceous and Pliocene. Angola is well known for his wonderful stepped planation surface : the highest is attribued to late Cretaceous, the intermediary one to Miocene, and the lowest to Pliocene. In Congo and Namibie, the succession of events is significantly different. In Transvaal and Namibie, a giant flexure affects a volcanic serie ending with basalts of lower Jurassic age. Tentatively the Highveld planation surface cutting across kimberlite pipes is attribued to late Cretaceous or Paleocene. The lowest step (Lowveld) appears related to the neogene accumulation. An intermediary surface cuts across the crystalline northern scarp and the top of the Lebombo Ridge. The best studied area of the Western Ghats consists of subhorizontal traps of paleocene age. Neither upper post-trappean planation surface, neither important lower steps were identified. The dissymetric bulge is supported by a thickened crust. Proved post-trappean faults are restricted to the shelf. But the thickest neogene sediments are chiefly tilted oceanwards. Source : Éditeur (via Persée) |
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| Article en ligne | https://www.persee.fr/doc/bagf_0004-5322_1982_num_59_489_7934 |
