TY - JOUR
T1 - Tectonic development, sedimentation and paleoceanography of the Scan Basin (southern Scotia Sea, Antarctica)
AU - Pérez, Lara F.
AU - Lodolo, Emanuele
AU - Maldonado, Andrés
AU - Hernández-Molina, F. Javier
AU - Bohoyo, Fernando
AU - Galindo-Zaldívar, Jesús
AU - Lobo, F. José
AU - Burca, Mihai
N1 - Funding Information:
This work was undertaken within the objectives of projects CTM2008-06386-CO2-01/02 and CTM2011-30241-C02-01/02. This research is also related with the CTM2012-39599-C03, IGCP-619 and INQUA 1204 Projects. The corresponding author acknowledges a JAE pre-doctoral grant from the Spanish National Research Council (CSIC). We thank OGS for allowing the first author to perform two short-term stays at their headquarters in 2012 and 2013 and the PRNA project “Drake” funded by the Italian Ministry of Education, University and Research for providing support. This work was also partially supported by the COMPASS consortium and performed in collaboration with the Continental Margins Research Group (CMRG) at Royal Holloway University of London (UK). We thank the Polar Marine Geosurvey Expedition (PMGRE), for the RAE MCS profile, and the Antarctic Seismic Data Library System, for access to data. Finally, we thank Philip Leat, as editor, the one anonymous reviewer and Gerhard Kuhn for the positive review of the first version of the manuscript that significantly helped to improve the final version of this contribution.
Publisher Copyright:
© 2014 Elsevier B.V.
PY - 2014/12/1
Y1 - 2014/12/1
N2 - The N-S trending Scan Basin is the easternmost deep basin north of the South Scotia Ridge, which is a geologically complex structural elevation that hosts the strike-slip boundary between the Scotia and Antarctic plates. We characterized the main morpho-structural features of the basin by analyzing the available multichannel seismic reflection profiles. The reconstruction of the seismo-stratigraphy reveals the growth patterns of the Scan Basin. Seismic data and gravity modeling support the interpretation that the basin is mainly floored by oceanic crust, however its northern and southern provinces exhibit different seismic attributes. Stratigraphic calibrations with adjacent regions together with the distribution of sedimentary units indicate that this basin was formed by rifting processes and subsequent spreading accretion from the Oligocene to the Miocene. This age attribution suggests that the Scan Basin might be one of the oldest oceanic basins of the southern Scotia Sea-possibly coeval with the Eocene-Oligocene opening of the Drake Passage. The basin is the most direct connection between the Weddell Sea and the Scotia Sea, whereas the stratigraphic features reveal the occurrence of major paleoceanographic changes. The initial phases of the evolution were influenced by mass-transport and turbidite processes of sediment supply from the nearby continental margins of the eastern tip of the Antarctic Peninsula. From the Middle Miocene to the Present-day, the eastward motion of the basin due to plate tectonic and the connection with the Weddell Sea through gateways enabled instauration of the overflow of Weddell Sea Deep Water (WSDW) into the Scan Basin. The WSDW forced the northward migration of the Circumpolar Deep Water (CDW) and became progressively dominant, controlling depositional patterns. The results that we report here should prove essential for understanding the formation of the Scotia Sea, the beginning of the Scotia Arc fragmentation, and the increasing role played by Weddell Sea/Scotia Sea water-mass exchange.
AB - The N-S trending Scan Basin is the easternmost deep basin north of the South Scotia Ridge, which is a geologically complex structural elevation that hosts the strike-slip boundary between the Scotia and Antarctic plates. We characterized the main morpho-structural features of the basin by analyzing the available multichannel seismic reflection profiles. The reconstruction of the seismo-stratigraphy reveals the growth patterns of the Scan Basin. Seismic data and gravity modeling support the interpretation that the basin is mainly floored by oceanic crust, however its northern and southern provinces exhibit different seismic attributes. Stratigraphic calibrations with adjacent regions together with the distribution of sedimentary units indicate that this basin was formed by rifting processes and subsequent spreading accretion from the Oligocene to the Miocene. This age attribution suggests that the Scan Basin might be one of the oldest oceanic basins of the southern Scotia Sea-possibly coeval with the Eocene-Oligocene opening of the Drake Passage. The basin is the most direct connection between the Weddell Sea and the Scotia Sea, whereas the stratigraphic features reveal the occurrence of major paleoceanographic changes. The initial phases of the evolution were influenced by mass-transport and turbidite processes of sediment supply from the nearby continental margins of the eastern tip of the Antarctic Peninsula. From the Middle Miocene to the Present-day, the eastward motion of the basin due to plate tectonic and the connection with the Weddell Sea through gateways enabled instauration of the overflow of Weddell Sea Deep Water (WSDW) into the Scan Basin. The WSDW forced the northward migration of the Circumpolar Deep Water (CDW) and became progressively dominant, controlling depositional patterns. The results that we report here should prove essential for understanding the formation of the Scotia Sea, the beginning of the Scotia Arc fragmentation, and the increasing role played by Weddell Sea/Scotia Sea water-mass exchange.
KW - Antarctica
KW - Basin analysis
KW - Bottom currents
KW - Reflection seismic and gravity
KW - Scotia Sea
KW - Weddell Sea
UR - http://www.scopus.com/inward/record.url?scp=84955172196&partnerID=8YFLogxK
U2 - 10.1016/j.gloplacha.2014.06.007
DO - 10.1016/j.gloplacha.2014.06.007
M3 - Article
AN - SCOPUS:84955172196
SN - 0921-8181
VL - 123
SP - 344
EP - 358
JO - Global and Planetary Change
JF - Global and Planetary Change
IS - Part B
ER -