| Institution: | UMR 7072, Laboratoire de Tectonique, UniversitéP. et M. Curie, Case 129, 4 place Jussieu, 75252 Paris Cedex 05, France;;UMR 6538 Domaines Océaniques, IUEM, Place Nicolas Copernic, 29280 Plouzané, France;;UMR 7097 Géosciences Marines, IPGP Case 89, 4 place Jussieu, 75252 Paris Cedex 05, France;;UMR 6526, Géosciences Azur, Observatoire océanologique, BP48, 06235 Villefranche sur mer cedex, France;;Division Géologie–Géochimie, Institut Français du Pétrole, 1–4 avenue de Bois Préau, 92852 Rueil Malmaison, France;;Directorate of Minerals, PO Box 205, PC 211 Salalah, Sultanate of Oman;;Ecole et Observatoire de Physique du Globe de Strasbourg, 5 rue RenéDescartes, 67084 Strasbourg, France;;Total, Tour Coupole, 2, Place de la Coupole, 92078 Paris –La Défense Cedex, France;;Centre d'Informatique Géologique, Ecole des Mines de Paris, 35 rue St-Honoré, 77305 Fontainebleau, France |
| Abstract: | A geophysical survey in the eastern Gulf of Aden, between the Alula–Fartak (52°E) and the Socotra (55°E) transform faults, was carried out during the Encens–Sheba cruise. The conjugate margins of the Gulf are steep, narrow and asymmetric. Asymmetry of the rifting process is highlighted by the conjugate margins (horst and graben in the north and deep basin in the south). Two transfer fault zones separate the margins into three segments, whereas the present‐day Sheba Ridge is divided into two segments by a transform discontinuity. Therefore segmentation of the Sheba Ridge and that of the conjugate margins did coincide during the early stages of oceanic spreading. Extensive magma production is evidenced in the central part of the western segment. Anomaly 5d was identified in the northern and southern parts of the oceanic basin, thus confirming that seafloor spreading in this part of Gulf of Aden started at least 17.6 Ma ago. |
