SALSA LEG2
Type | Oceanographic cruise |
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Ship | L'Atalante |
Ship owner | Ifremer |
Dates | 04/05/2014 - 24/05/2014 |
Chief scientist(s) | ASLANIAN Daniel , MOULIN Maryline , EVAIN Mikael |
GEO-OCEAN - UMR 6538 Univ. Brest, CNRS, Ifremer, Univ. Bretagne Sud Place Nicolas Copernic 29280 Plouzané |
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DOI | 10.17600/14013700 |
Objective | The North-east Brazilian margins have the specificity of being highly segmented, in different structural and tectonic heritage contexts, and are thus an idea area to study the influence tectonic heritage has on margin formation. The aim of the SALSA (SERGIPE ALAGOAS SEISMIC ACQUISITION) project is to study this part of the Brazilian margins and more specifically to test the influence of tectonic heritage on the forming of continental margins in various contexts (divergent, transform or oblique extension). We proposed to obtain complete cross-sections of the Jequitinhonha-Camamu-Jacuipe-Sergipe-Alagoas / Gabon system, initially on the Brazilian side, in order to obtain 3D imagery of its deep structure and to test various hypotheses on 1) variation in deep margin structures along this segment of margin, and 2) the nature of the crust in the transitional domain (between the fit and the ocean-continent boundary). Why is it already thinned? Is this 10km crust made up purely of an upper crust? Is there any exhumed mantle? 3) the position of the ocean crust, 4) rifting models in oblique and divergent extension systems. To do this, we propose to acquire vertical multichannel seismic reflection data using Genavir's facilities, as well as seismic reflection and refraction data, using ocean-bottom stations (OBS) and stations onshore. Leg 1 took place from 04/04 to 03/05 and leg 2 from 04/05 to 24/05. This falls under the SALSA project. |