|
|
|
|
|
| Watremez, L.; Burov, E.; D'Acremont, E.; Leroy, Sylvie; Huet, B.; Lepourhiet, L.; Bellahsen, N.. |
| Physical properties of the mantle lithosphere have a strong influence on the rifting processes and rifted structures. In particular, in context of rifting, two of these properties have been overlooked: (1) Mohr-Coulomb plasticity (localizing pressure dependent) may not be valid at mantle depths as opposed to nonlocalizing pressure-independent plasticity (hereafter, perfect plasticity), and (2) lithosphere buoyancy can vary, depending on the petrological composition of the mantle. Focussing on the Arabian plate, we show that the lithosphere may be negatively buoyant. We use thermomechanical modeling to investigate the importance of mantle rheology and composition on the formation of a passive margin, ocean-continent transition (OCT) and oceanic basin. We... |
| Tipo: Text |
Palavras-chave: Thermomechanical modeling; Rifting; Ocean-continent transition; Plasticity; Lithosphere buoyancy; Gulf of Aden. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00199/31070/29483.pdf |
| |
|
|
| D'Acremont, E; Leroy, S; Beslier, Mo; Bellahsen, N; Fournier, M; Robin, C; Maia, M; Gente, P. |
| The Gulf of Aden is a young and narrow oceanic basin formed in Oligo-Miocene time between the rifted margins of the Arabian and Somalian plates. Its mean orientation, N75 degrees E, strikes obliquely (50 degrees) to the N25 degrees E opening direction. The western conjugate margins are masked by Oligo-Miocene lavas from the Afar Plume. This paper concerns the eastern margins, where the 19-35 Ma breakup structures are well exposed onshore and within the sediment-starved marine shelf. Those passive margins, about 200 km distant, are non-volcanic. Offshore, during the Encens-Sheba cruise we gathered swath bathymetry, single-channel seismic reflection, gravity and magnetism data, in order to compare the structure of the two conjugate margins and to reconstruct... |
| Tipo: Text |
Palavras-chave: Continental margins; Gulf of Aden; Ocean-continent transition; Plate divergence; Rifted margin; Seafloor spreading. |
| Ano: 2005 |
URL: https://archimer.ifremer.fr/doc/00230/34079/32539.pdf |
| |
|
|
| D'Acremont, Elia; Leroy, Sylvie; Maia, Marcia; Patriat, Philippe; Beslier, Marie-odile; Bellahsen, Nicolas; Fournier, Marc; Gente, Pascal. |
| Magnetic and gravity data gathered during the Encens-Sheba cruise (2000 June) in the eastern Gulf of Aden provide insights on the structural evolution of segmentation from rifted margins to incipient seafloor spreading. In this study, we document the conjugate margins asymmetry, confirm the location of the ocean-continent transition (OCT) previously proposed by seismic data, and describe its deep structure and segmentation. In the OCT, gravity models indicate highly thinned crust while magnetic data indicate presence of non-oceanic high-amplitude magnetic anomalies where syn-rift sediments are not observed. Thus, the OCT could be made of ultra-stretched continental crust intruded by magmatic bodies. However, locally in the north, the nature of the OCT... |
| Tipo: Text |
Palavras-chave: Gulf of Aden; Kinematic evolution; Ocean-continent transition; Passive continental margin; Seafloor spreading; Segmentation. |
| Ano: 2006 |
URL: https://archimer.ifremer.fr/doc/00234/34561/33314.pdf |
| |
|
|
|
