| Texto completo | |
| Autor(es): |
Salazar-Mora, Claudio Alejandro
;
Sacek, Victor
Número total de Autores: 2
|
| Tipo de documento: | Artigo Científico |
| Fonte: | TECTONICS; v. 42, n. 2, p. 19-pg., 2023-02-01. |
| Resumo | |
Tectonic quiescence is a period of nearly null relative plate motion. During the Atlantic Ocean opening, rifting cut across continental segments of supercontinent Pangea that had been through different periods of quiescence, which varied from tens to hundreds of Myr. Using numerical models, we explored the effects of quiescence between orogeny and rifting on the pre-rift lithosphere and subsequent conjugate rifted margin configuration. Our model results showed that quiescence of & sim;30 & ndash;60 Myr caused wide orogenic wedges (& gt;300 km) to be heated beneath their centers, which led to the breakup of the lithospheric mantle before the breakup of the continental crust during rifting, resulting in hyperextended conjugate rifted margins. In these scenarios, continental lithosphere breakup away from the suture contributed to the preservation of previously subducted lower crust along the subduction zone. Long periods of tectonic quiescence (& sim;100 Myr) experienced by a wide orogen permitted efficient orogenic collapse and lateral spreading, with pronounced lithospheric thermal weakening. Consequently, post-quiescence rifting reactivated the suture and effectively drove plate eduction, exhuming most of the subducted continental lower crust and mantle lithosphere. Ultimately, ultra-wide domains developed into asymmetric conjugate margins. Contrastingly, in narrow orogenic wedges (& lt;200 km), different quiescence durations had minor effects on the margin architecture. In these cases, a longer quiescence time contributed to a larger preservation of subducted crust in the fossil subduction zone after rifting. Our models agree with conjugate rifted margins in the North and South Atlantic, which probably developed after the collapse of wide orogens and subsequent periods of tectonic quiescence. (AU) | |
| Processo FAPESP: | 17/10467-4 - Modelagem numérica geodinâmica do Sistema de Rifte do Atlântico Sul: implicações para a evolução Neoproterozoica do Orógeno Araçuaí e dos cratons São Francisco e Congo |
| Beneficiário: | Claudio Alejandro Salazar Mora |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 17/00461-9 - Desenvolvimento de eletrodos impressos modificados por azul da Prússia e análogos para dispositivos analíticos integrados |
| Beneficiário: | Juliano Alves Bonacin |
| Modalidade de apoio: | Bolsas no Exterior - Pesquisa |
| Processo FAPESP: | 17/24870-5 - Evolução da bacia hidrográfica do Rio Amazonas: soerguimento dos Andes, clima e outros processos geodinâmicos |
| Beneficiário: | Victor Sacek |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |