FN Archimer Export Format
PT J
TI Imaging proto-oceanic crust off the Brazilian Continental Margin
BT 
AF KLINGELHOEFER, Frauke
   EVAIN, Mikael
   AFILHADO, A.
   RIGOTI, Caesar
   LOUREIRO, Afonso
   ALVES, D.
   LEPRETRE, Angelique
   MOULIN, Maryline
   SCHNURLE, Philippe
   BENABDELLOUAHED, Massinissa
   BALTZER, Agnes
   RABINEAU, Marina
   FELD, Aurelie
   VIANA, A.
   ASLANIAN, Daniel
AS 1:1;2:1;3:1,2;4:3;5:2;6:2;7:1;8:1;9:1;10:1;11:4;12:5;13:6;14:3;15:1;
FF 1:PDG-REM-GM-LGG;2:PDG-REM-GM-LGG;3:;4:PDG-REM-GM-LGG;5:;6:;7:PDG-REM-GM-LGG;8:PDG-REM-GM-LGG;9:PDG-REM-GM-LGG;10:PDG-REM-GM-LGG;11:PDG-REM-GM-LGG;12:;13:PDG-DGD-DMON-PF;14:;15:PDG-REM-GM-LGG;
C1 IFREMER, Dept Marine Geosci, ZI Pointe Diable, F-29280 Plouzane, France.
   Univ Lisbon, Fac Ciencias, IDL, P-1749016 Lisbon, Portugal.
   Petrobras SA, Petrobras Res Ctr, Rio De Janeiro, Brazil.
   Univ Nantes, Inst Geog & Amenagement Reg, LETG UMR CNRS 6554, Geolittomer, F-44312 Nantes 3, France.
   Inst Univ Europeen Mer, UMR6538, F-29280 Plouzane, France.
   IFREMER, Ctr Brest, DEC QAE, Genavir,ZI Pointe Diable, F-29280 Plouzane, France.
C2 IFREMER, FRANCE
   UNIV LISBON, PORTUGAL
   PETROBRAS, BRAZIL
   UNIV NANTES, FRANCE
   UBO, FRANCE
   IFREMER, FRANCE
SI BREST
SE PDG-REM-GM-LGG
   PDG-DGD-DMON-PF
UM LGO
IN WOS Ifremer jusqu'en 2018
   copubli-france
   copubli-europe
   copubli-univ-france
   copubli-int-hors-europe
   copubli-sud
IF 2.484
TC 35
UR https://archimer.ifremer.fr/doc/00242/35296/33826.pdf
LA English
DT Article
CR SANBA (SANTOS BASIN) LEG1
   SANBA (SANTOS BASIN) LEG2
BO L'Atalante
DE ;Controlled source seismology;Seismic tomography;Mid-ocean ridge processes;Continental margins: divergent;Continental tectonics: extensional;Crustal structure;South America
AB During the Sanba (Santos basin seismic transect) experiment in 2010–2011, a 380-km-long combined wide-angle and reflection seismic profile has been acquired using 30 ocean-bottom seismometers, a 4.5 km seismic streamer and a 8900 in.3 airgun array. The Sanba 3 profile crosses the southern flank of the Sao Paulo Plateau, the Sao Paulo Ridge and the easternmost Santos Basin in an east–west direction. Its eastern end is located on undisturbed oceanic crust. Tomographic and forward modelling of the wide-angle seismic data reveals that the sedimentary thickness is variable with only 1–2 km on top of the ridge and thickening to 4–5 km in the basin. Crustal thickness at the ridge is about 18 km and the relative layer thickness and velocity gradients indicate a continental origin of this ridge. The eastern Santos Basin is underlain by crust of only 5 km thickness, characterized by high seismic velocities between 6.20 km s–1 in the upper crust and 7.40 km s–1 in the lower crust. Three hypotheses for the nature of the crust in this region are tested here: (i) thinned continental crust, (ii) serpentinized upper mantle material, (iii) thin oceanic crust. As seismic velocity gradients seem to rule out a continental origin of this region, and clear Moho reflections argue against serpentinized upper mantle, we propose that the crust underlying the easternmost Santos Basin is of oceanic origin. Deviations from normal oceanic crustal velocities in the lower crust (6.70–7.00 km s–1) can be explained by accretion at slow spreading rates leading to the inclusion of serpentinite into the lower crust at the onset of organized seafloor spreading.
PY 2015
PD JAN
SO Geophysical Journal International
SN 0956-540X
PU Oxford Univ Press
VL 200
IS 1
UT 000350041600034
BP 471
EP 488
DI 10.1093/gji/ggu387
ID 35296
ER

EF