The Main Ethiopian Rift is the northernmost sector of the East African Rift System, connecting this continental rift to the oceanic spreading centres of the Red Sea and Gulf of Aden. It is considered an ideal place to analyse the evolution of continental extension, the rupture of lithospheric plates and the dynamics by which distributed continental deformation is progressively focused at oceanic spreading centres. The magmatic and tectonic evolution of the Main Ethiopian Rift represented one of the main research topics of the late Fabrizio Innocenti, who promoted an advanced approach based on integration of the "classical" structural and petrological approaches with modern techniques such as analogue modelling. This analysis, together with other field geological, petrological and geophysical investigations, have clarified some important aspects of the evolution of continental rifting in the area, in terms of rift progression, relations between deformation and magmatism and role of transverse structures in accommodating the extensional deformation. Integration of old and new data suggests that rift evolution is not a simple uniform process, but a complex succession of episodes of extension and relative quiescence that may be reconducted to a southward progression of the extensional deformation from the Afar region. Rift location has been most probably controlled by the reactivation of a NE-SW pre-existing lithospheric zone of weakness within a pre-structured lithosphere where transverse structures have been proven to exert a significant control on the accommodation of deformation and on the distribution of strong volcanic activity outside the rift. In the different segments, initial rifting is marked by widespread ignimbritic activity and boundary faults activation, followed by faulting within the rift floor associated with bimodal Quaternary volcanism. This riftward migration of the volcano-tectonic activity documents a transition from fault-dominated extension proc
The volcano-tectonic activity of the Main Ethiopian Rift (East Africa): insights into the evolution of continental rifting.
Corti G;Bonini M;
2009
Abstract
The Main Ethiopian Rift is the northernmost sector of the East African Rift System, connecting this continental rift to the oceanic spreading centres of the Red Sea and Gulf of Aden. It is considered an ideal place to analyse the evolution of continental extension, the rupture of lithospheric plates and the dynamics by which distributed continental deformation is progressively focused at oceanic spreading centres. The magmatic and tectonic evolution of the Main Ethiopian Rift represented one of the main research topics of the late Fabrizio Innocenti, who promoted an advanced approach based on integration of the "classical" structural and petrological approaches with modern techniques such as analogue modelling. This analysis, together with other field geological, petrological and geophysical investigations, have clarified some important aspects of the evolution of continental rifting in the area, in terms of rift progression, relations between deformation and magmatism and role of transverse structures in accommodating the extensional deformation. Integration of old and new data suggests that rift evolution is not a simple uniform process, but a complex succession of episodes of extension and relative quiescence that may be reconducted to a southward progression of the extensional deformation from the Afar region. Rift location has been most probably controlled by the reactivation of a NE-SW pre-existing lithospheric zone of weakness within a pre-structured lithosphere where transverse structures have been proven to exert a significant control on the accommodation of deformation and on the distribution of strong volcanic activity outside the rift. In the different segments, initial rifting is marked by widespread ignimbritic activity and boundary faults activation, followed by faulting within the rift floor associated with bimodal Quaternary volcanism. This riftward migration of the volcano-tectonic activity documents a transition from fault-dominated extension procI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
