| Title: |
Lithospheric structuration onshore-offshore of the Sergipe-Alagoas passive margin, NE Brazil, based on wide-angle seismic data |
| Authors: |
Pinheiro, Joao Marcelo; Schnurle, Philippe; Evain, Mikael; Afilhado, A.; Gallais, Flora; Klingelhoefer, Frauke; Loureiro, Afonso; Fuck, R.; Soares, J.; Cupertino, J. A.; Viana, A.; Rabineau, Marina; Baltzer, Agnes; Benabdellouahed, Massinissa; Dias, N.; Moulin, Maryline; Aslanian, Daniel; Morvan, Laetitia; Maze, Jean-pierre; Pierre, Delphine; Pitel-roudaut, Mathilde; Rio, I; Alves, D.; Barros Junior, P.; Biari, Youssef; Corela, C.; Crozon, Jacques; Duarte, J. L.; Ducatel, Cecile; Falcao, C.; Fernagu, Philippe; Le Piver, David; Mokeddem, Zohra; Pelleau, Pascal; Rigoti, C.; Roest, Walter; Roudaut, Mickael |
| Source: |
Journal Of South American Earth Sciences (0895-9811) (Pergamon-elsevier Science Ltd), 2018-12 , Vol. 88 , P. 649-672 |
| Publisher Information: |
Pergamon-elsevier Science Ltd |
| Publication Year: |
2018 |
| Collection: |
Ifremer (French Research Institute for Exploitation of the Sea): Archimer |
| Subject Terms: |
South Atlantic ocean; NE Brazil; Sergipe-Alagoas basin; Passive margins; Wide-angle refraction seismics; Crustal structure; Tectonic inheritance |
| Description: |
The structure and nature of the crust underlying the Camamu-Almada-Jequitinhonha-Sergipe-Alagoas basins System, in the NE Brazilian margin, were investigated based on the interpretation of 12 wide-angle seismic profiles acquired during the SALSA (Sergipe ALagoas Seismic Acquisition) experiment in 2014. In this work, we present two 220-km-long NW-SE combined wide-angle and reflection seismic profiles, SL 01 and SL 02, that have been acquired using 15 ocean-bottom-seismometers along each profile, offshore the southern part of the Sergipe Alagoas Basin (SAB), north of the Vaza-Barris Transfer zone. The SL 02 has a 150-km long inland continuation with 20 land-seismic-stations until the Sergipano Fold Belt (SFB). Wide-angle seismic forward modeling allows us to precisely divide the crust in three domains: beneath the continental shelf, a ∼100 km wide necking zone is imaged where the continental crust thins from ∼35 km on the Unthinned Continental Domain, which displays a three-layered crust structure, to less than 8 km on the Oceanic Crust Domain. In the necking zone, the upper and the middle layers thin dramatically and almost disappear, while the Moho discontinuity shows clear PmPs. The Continental-Oceanic Crust Boundary (COB) is located at ∼80 km from the coastline and is marked by intracrustal seismic reflectors and changes in the seismic velocity, showing a sharp transition. On profile SL02, the oceanic crust is perturbed by a volcanic edifice together with an anomalous velocity zone underneath the area. |
| Document Type: |
article in journal/newspaper |
| File Description: |
application/pdf |
| Language: |
English |
| Relation: |
https://archimer.ifremer.fr/doc/00461/57263/59315.pdf; https://archimer.ifremer.fr/doc/00461/57263/ |
| DOI: |
10.1016/j.jsames.2018.09.015 |
| Availability: |
https://archimer.ifremer.fr/doc/00461/57263/59315.pdf; https://doi.org/10.1016/j.jsames.2018.09.015; https://archimer.ifremer.fr/doc/00461/57263/ |
| Accession Number: |
edsbas.EE4F05F9 |
| Database: |
BASE |