English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/26465
Share/Impact:
Statistics
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

Title

Recent sedimentary processes in the Prestige site area (Galicia Bank, NW Iberian Margin) evidenced by high-resolution marine geophysical methods

AuthorsHernández-Molina, Francisco J.; Llave, Estefanía; Ercilla, Gemma ; Maestro, Adolfo; Medialdea, Teresa; Ferrin, A.; Somoza, Luis; Gràcia, Eulàlia ; Masson, Douglas G.; García, Marga ; Vizcaino, A. ; León, Ricardo
KeywordsGalicia Bank
Echo-character analysis
High-resolution seismic profiles
Swath bathymetry
TOBI sidescan sonar
Sedimentary processes
TOBI
Issue Date11-Mar-2008
PublisherElsevier
CitationMarine Geology 249(1-2): 21-45 (2008)
AbstractAn echo-character analysis of the oil tanker Prestige wreck area was undertaken using high-resolution marine geophysical methods (TOPAS and airgun seismic-reflection profiles, multibeam echosounder and TOBI sidescan sonar). Integration and comparison of the results using all these methods is presented given some practical applications for indirect near-surface and seafloor interpretations. Ten different echo types were identified and grouped into four main classes: I) distinct; II) indistinct; III) irregular and IV) hyperbolic. Echo-character distribution enabled us to determine recent sedimentary processes in the area. Two major depositional systems can be found through the identification of these sedimentary processes: a) a slope depositional system (SDS) located in the eastern and central area, where mass-movement processes are dominant and b) a turbiditic Main Channel depositional system (TDS) located in the western area where channel-related processes are dominant. Both of these interact over the half-graben structure of the southwestern sector of the Galicia Bank, where the Prestige wreck is located. Within the SDS, erosive and depositional mass-movement processes characterised a complex depositional system. Erosive processes occur on the fault scarp, channels head, inter-lobe channels and distal part of the sedimentary lobes. Moreover, depositional processes take place on the top of the fault scarp, sedimentary wedges, sedimentary lobes, and on the west flank of the Main Channel. Both depositional systems interact, but the SDS should be more active during fault-scarp reactivation periods, through relief rejuvenation and new exposed deposits. Microearthquake activity would favour the available materials, being weathered, eroded and transported by mass-movements. In such a situation, the TDS acts as the main collector of eroded sediment derived from the fault scarp throughout the SDS being responsible for its evacuation into the Iberian Abyssal Plain. However, outside of fault reactivation periods, the SDS is less active (such as during the present situation)
DescriptionSpecial issue Geological characterization of the Galicia Bank Region (Atlantic Ocean, NW Iberia).-- 24 pages, 9 figures, 1 table
Publisher version (URL)http://dx.doi.org/10.1016/j.margeo.2007.09.011
URI10261/26465
DOI10.1016/j.margeo.2007.09.011
ISSN0025-3227
Appears in Collections:(ICM) Artículos
(UTM) Artículos
Files in This Item:
There are no files associated with this item.
Show full item record
Review this work
 

Related articles:


WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.