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  • During austral summer1989-90 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 1284 km of 30-fold multichannel seismic reflection (MCS) data were collected between longitude 165 and 176 degrees East, and latitude 61 and 66 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 22.5 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 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 Summer1991-92 the National Institute of Oceanography and Applied Geophysics - OGS conducted marine geological and geophysical surveys over the Antarctic Peninsular and the Bransfield Strait. During this cruise approximately 3407 km of 30-fold multichannel seismic reflection (MCS) data were collected in the Antarctic Peninsular and the Bransfield Strait between longitudes 50 and 78 degrees West, and latitudes 60 and 68 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 a total volume of 71.96 litres fired approximately 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 the 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 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 the Antarctic summer 1988-89, a geophysical survey (seismic, gravity and magnetics) was carried out by the National Institute of Oceanography and Applied Geophysics - OGS of Trieste, Italy, in the Ross Sea with the Research Vessel O.G.S. Explora. 23 lines of total length 4113.1 Km were collected. The cruise began on December 10,1988 from the harbor of Hobart (Australia) and ended on January 15, 1989, with its arrival in Dunedin (New Zealand). Gravimetric and geomagnetic data were continuously acquired during the cruise, with minor interruptions due to adverse sea conditions. The multichannel seismic survey was run in the Ross Sea from December 18 to January 8. The project has been financially supported by the Italian Antarctic Program (PNRA).

  • 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.

  • 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).

  • 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).

  • During Austral Summer1991-92 the National Institute of Oceanography and Applied Geophysics - OGS conducted marine geological and geophysical surveys over the Antarctic Peninsular and the Bransfield Strait. During this cruise approximately 3407 km of 30-fold multichannel seismic reflection (MCS) data were collected in the Antarctic Peninsular and the Bransfield Strait between longitudes 50 and 78 degrees West, and latitudes 60 and 68 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 a total volume of 71.96 litres fired approximately 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 the 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.

  • In December 1989, the National Institute of Oceanography and Applied Geophysics - OGS conducted marine geological and geophysical surveys off the Pacific Margin of the Antarctic Peninsula, in the Weddell Sea and over Admundsen Sea. This cruise collected approximately 3,478.4 km of 30-fold multichannel seismic reflection (MCS) data. The surveys extended between longitudes 41 and 99 degrees west , and between latitudes 61 and 69 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 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.