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  • Complementary with the ANTSSS project funded by EUROFLEETS, ODYSSEA aimed at investigating the sediment drifts to the west of the Hillary Canyon (Ross Sea continental margin) by means of seismic and oceanographic data to contribute to the understanding of past and present ocean dynamics and glacial history of this Antarctic sector. During the 32nd PNRA expedition, OGS Explora collected over 240 km of Single Channel Seismics (SCS), 2700 km2 of bathymetry, 500 km of sub-bottom, 6 gravity cores for a total of nearly 30 m of sediments, 4 box cores, 25 XBT launches, 2 rosette casts with water sampling, CTD, L-ADCP, turbidity and florescence probes. Part of the seismic data have been initially published in Conte R et al (2021) Bottom current control on sediment deposition between the Iselin Bank and the Hillary Canyon (Antarctica) since the late Miocene: An integrated seismic-oceanographic approach. Deep-Sea Research Part I: Oceanographic Research Papers 176, art. no. 103606, DOI: 10.1016/j.dsr.2021.103606

  • During austral summer 1990/91, the National Institute of Oceanography and Applied Geophysics - OGS conducted marine geological and geophysical surveys off Wilkes Land, and around the Balleny Islands. During this cruise 1935 km of 30-fold multichannel seismic reflection (MCS) data were collected between longitude 150 and 169 degrees East, and latitude 56 and 64 degrees South. The surveys were carried out by the research vessel OGS Explora. The 14 second, 4 ms sample rate, digital MCS data were recorded on a SERCEL SN 358 DMX system. The source consisted of an airgun array with a total volume of 74.8 litres fired every 50 meters into a 3000 m cable consisting of 120 hydrophone groups towed at an average depth of 12 m. A GPS + TRANSIT satellite receiver system was used for navigation. Processing of the data generally followed a conventional sequence: Reformat, Quality control, Amplitude recovery, Deconvolution, Velocity analysis, NMO corrections, Mute, Trace weighting, Stack, Mixing, Filter, Dynamic trace equalisation.

  • Complementary with the ODYSSEA project funded by PNRA, ANTSSS aimed at finding evidence for Late Pleistocene sedimentary signatures of major changes in the extent of grounded, marine based ice sheets in the Ross Sea, as preserved in slope/ rise drift deposits by means of seismic and oceanographic data. During the 2017 expedition, OGS Explora collected over 450 km of Single Channel Seismics (SCS), 1575 km2 of bathymetry, >500 km of sub-bottom, and oceanographic data, including Conductivity Temperature Depth (CTD), Acoustic Doppler Current Profiler (ADCP), Lowered-ADCP, Expendable Bathythermograph (XBT) and turbidity data. Part of the seismic data have been initially published in Gales et al. (2021) Role of dense shelf water in the development of Antarctic submarine canyon morphology. Geomorphology, 372, art. no. 107453. DOI: 10.1016/j.geomorph.2020.107453

  • Complementary with the ODYSSEA project funded by PNRA, ANTSSS aimed at finding evidence for Late Pleistocene sedimentary signatures of major changes in the extent of grounded, marine based ice sheets in the Ross Sea, as preserved in slope/ rise drift deposits by means of seismic and oceanographic data. During the 2017 expedition, OGS Explora collected over 450 km of Single Channel Seismics (SCS), 1575 km2 of bathymetry, >500 km of sub-bottom, and oceanographic data, including Conductivity Temperature Depth (CTD), Acoustic Doppler Current Profiler (ADCP), Lowered-ADCP, Expendable Bathythermograph (XBT) and turbidity data. Part of the seismic data have been initially published in Gales et al. (2021) Role of dense shelf water in the development of Antarctic submarine canyon morphology. Geomorphology, 372, art. no. 107453. DOI: 10.1016/j.geomorph.2020.107453

  • Complementary with the ANTSSS project funded by EUROFLEETS, ODYSSEA aimed at investigating the sediment drifts to the west of the Hillary Canyon (Ross Sea continental margin) by means of seismic and oceanographic data to contribute to the understanding of past and present ocean dynamics and glacial history of this Antarctic sector. During the 32nd PNRA expedition, OGS Explora collected over 240 km of Single Channel Seismics (SCS), 2700 km2 of bathymetry, 500 km of sub-bottom, 6 gravity cores for a total of nearly 30 m of sediments, 4 box cores, 25 XBT launches, 2 rosette casts with water sampling, CTD, L-ADCP, turbidity and florescence probes. Part of the seismic data have been initially published in Conte R et al (2021) Bottom current control on sediment deposition between the Iselin Bank and the Hillary Canyon (Antarctica) since the late Miocene: An integrated seismic-oceanographic approach. Deep-Sea Research Part I: Oceanographic Research Papers 176, art. no. 103606, DOI: 10.1016/j.dsr.2021.103606

  • During Austral Summer 1989-90, the National Institute of Oceanography and Applied Geophysics - OGS, conducted marine geological and geophysical surveys off South Pacific ocean, in the Weddell Sea over Bellingshausen Sea, in the Ross Sea and over Admundsen Sea. This cruise collected approximately 8763 km of multichannel seismic reflection (MCS) data. The surveys extended, in diferent area, between longitudes 34 and 172 degrees west , and between latitudes 59 and 76 degrees south. The surveys were carried out by the research vessel OGS Explora. The digital MCS data were recorded on a SERCEL SN 358 DMX system. The source consisted of an airgun array with variable configuration from a total volume of 45.16 litres fired approximately every 50 meters. A GPS + TRANSIT satellite receiver system was used for navigation. Processing of the data generally followed a conventional sequence: Reformat, Trace-sum with differential NMO, Quality control, Amplitude recovery, Deconvolution, Velocity analysis, NMO corrections, Mute, Trace weighting, Stack, Mixing, Filter, Balance.

  • During austral summer 1988/89, the National Institute of Oceanography and Applied Geophysics - OGS conducted marine geological and geophysical surveys off Wilkes Land, and around the Balleny Islands. During this cruise 3045 km of 30-fold multichannel seismic reflection (MCS) data were collected between longitude 152 and 169 degrees East, and latitude 60 and 68 degrees South. The surveys were carried out by the research vessel OGS Explora. The 12 second, 4 ms sample rate, digital MCS data were recorded on a SERCEL SN 358 DMX system. The source consisted of an airgun array with a total volume of 45.16 litres fired every 50 meters into a 3000 m cable consisting of 120 hydrophone groups towed at an average depth of 12 m. A GPS + TRANSIT satellite receiver system was used for navigation. Processing of the data generally followed a conventional sequence: Reformat, Trace-sum with differential NMO, Resample to 8 ms, Quality control, Amplitude recovery, Deconvolution, Velocity analysis, NMO corrections, Mute, Trace weighting, Stack, Mixing, Filter, Dynamic trace equalisation.

  • During austral summer1994/95, the National Institute of Oceanography and Applied Geophysics - OGS, on board the research vessel OGS-Explora, conducted marine geological and geophysical surveys along the Antarctic Peninsula. The SANSCRITO (Seismic ANalysis SCotia RIdge Tectonic Outcome) programme was a seismic exploration cruise in the Scotia Sea to understand the tectonic history and evolution of the region; data were collected between longitude 45 and 54 degrees West, and latitude 59 and 65 degrees South. During this programme 1990 km of 30-fold multichannel seismic reflection (MCS) data, 14 second records, 4 ms sample rate, were recorded on a SERCEL SN 358 DMX system. The source consisted of an airgun array with a total volume of 80 litres fired every 50 meters into a 3000 m cable consisting of 120 hydrophone groups towed at an average depth of 12 m. A GPS + TRANSIT satellite receiver system was used for navigation. The Chief Scientist on this programme was: Emanuele Lodolo of the National Institute of Oceanography and Applied Geophysics - OGS, Borgo Grotta Gigante n. 42/C, 34010 Sgonico (Trieste), Italy. Processing of the data generally followed a conventional sequence: Reformat, Trace-sum with differential NMO, Quality control, Amplitude recovery, Deconvolution, Velocity analysis, NMO corrections, Mute, Trace weighting, Stack, Mixing, Filter, and Dynamic trace equalisation.

  • During Austral Summer1990-91 the National Institute of Oceanography and Applied Geophysics - OGS conducted marine geological and geophysical surveys in the Ross Sea, over Weddel Sea and in the Balleny Zone of the MacQuarie Triple Junction. This cruise collected approximately 6036 km of multichannel seismic reflection (MCS) data. The surveys extended, in different areas, between longitudes 37 and 56 degrees west, and between latitudes 59 and 62 degrees south (Weddel Sea), between longitudes 171 east and 178 degrees west, and between latitudes 71 and 73 degrees south (Ross Sea), between longitudes 150 and 158 degrees east , and between latitudes 51 and 62 degrees south (Balleny). The surveys were carried out by the research vessel OGS Explora. The digital MCS data were recorded on a SERCEL SN 358 DMX system. The source consisted of an airgun array with variable configuration from a total volume of 45.16 litres fired approximately every 50 meters. A GPS + TRANSIT satellite receiver system was used for navigation. Processing of the data generally followed a conventional sequence: Reformat, Trace-sum with differential NMO, Quality control, Amplitude recovery, Deconvolution, Velocity analysis, NMO corrections, Mute, Trace weighting, Stack, Mixing, Filter, Balance.

  • High-resolution multichannel seismic profiles have been collected in January–March 2017 by OGS on the continental rise off the Sabrina Coast (East Antarctica). The data were acquired as part of the Italian Program of Antarctic Research (PNRA) TYTAN “Totten Glacier dynamics and Southern Ocean circulation impact on depositional processes since the Mid- to Late Cenozoic” project (PI: F. Donda-OGS) during the Australian Marine National Facility survey IN2017-V01 on board the RV Investigator. TYTAN was embedded in to the Australian project "Interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles” that aimed to understand the interaction of Totten Glacier and its ice drainage basin with the Southern Ocean during periods of warming and ice-sheet retreat in the Pleistocene and Holocene. In order to achieve these scientific objectives, three areas were identified for the geophysical and oceanographic survey: two on the continental slope and rise off Sabrina Coast and one on the continental shelf, which was not investigated because it remained covered by sea ice throughout the season. Expanded and well-preserved sedimentary successions imaged on the TYTAN seismic data highlight the potential of this region for deep ocean drilling, which will provide unprecedented history of the glaciers evolution in the Aurora Basin and their sensitivity to climate change under different background state conditions. In fact, TYTAN seismic data played a crucial role in the identification of potential drilling sites for the IODP 1002 Proposal “Totten Glacier Climate Vulnerability under varying Neogene climate conditions: Lessons for East Antarctic Ice Sheet climate sensitivity” (under review).