HR: 0800h
AN: V21B-0605    [Abstracts]
TI: The Azores Triple Junction zone: a highly detailed multibeam bathymetry survey
AU: * Luis, J
EM: jluis@ualg.pt
AF: Universidade Do Algarve, CIMA, CAmpus de Gambelas, Faro, 8000, Portugal
AU: Lourenço, N
EM: nlouren@ualg.pt
AF: Universidade Do Algarve, CIMA, CAmpus de Gambelas, Faro, 8000, Portugal
AU: Mata, J
AF: Universidade de Lisboa, Centro de Geologia, Campo Grande, Lisboa, 1200, Portugal
AU: Miranda, J M
AF: Universidade de Lisboa, CGUL, Campo Grande, Lisboa, 1200, Portugal
AU: Madureira, P
EM: jmata@fc.ul.pt
AF: Universiade de Évora, Centro de Geofisica de Évora, Évora, 7000, Portugal
AU: Goslin, J
EM: goslin@univ-brest.fr
AF: Domaines Océaniques, UMR CNRS-UBO 6538, Brest, 6538, France
AU: Perrot, J
EM: Julie.Perrot@univ-brest.fr
AF: Domaines Océaniques, UMR CNRS-UBO 6538, Brest, 6538, France
AU: Simão, N
EM: nuno.simao@univ-brest.fr
AF: Domaines Océaniques, UMR CNRS-UBO 6538, Brest, 6538, France
AB: We present here the results of a high precision bathymetric mapping of the Azores Triple Junction zone, close to the Mid-Atlantic Ridge. The survey was made with an EM300 on water depths between 1000 and 2000m, assuring its optimal behavior and hence the production of a high resolution grid of 50 m x 50 m. The STRIPAREA cruise was sailed on 2006 on board the N/O Suroit, as a result of a international collaboration involving CIMA (UALG), CGUL (ULIS) and the French Research lab: UMR6538/CNRS from Brest. Analysis of the data is ongoing but several observations can be outlined. We show that the TJ area closet to the MAR is a complex tectonic area, largely depleted from volcanic constructs. This is in clear contrast with the much higher magmatic budget observed in the adjoining MAR axis to the West and Faial Ridge to the East. The fault pattern is organised into three main directions: WSW-ENE, NW-SE, WNW- ESE disrupting nearly N-S MAR generated Abyssal hill fabric and controlling several basins. The East side of the North Azores Fracture Zone is not a continuous structure but it is interrupted at one location by ridge parallel constructions.
DE: 8137 Hotspots, large igneous provinces, and flood basalt volcanism
DE: 8410 Geochemical modeling (1009, 3610)
DE: 8413 Subduction zone processes (1031, 3060, 3613, 8170)
DE: 8416 Mid-oceanic ridge processes (1032, 3614)
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2007 Fall Meeting