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  • We present here the Multichannel Seismic metadata collected in 2022 by the PNRA19_00022 COLLAPS project "Cook glacier-Ocean system, sea LeveL and Antarctic Past Stability" Principal Investigator: L. De Santis OGS ldesantis@ogs.it The data set consist of ca. 300 km of multichannel seismic profiles collected with the R/V L. Bassi employing 2 x 210 cu.in. GI Gun and a 1500 m long digital streamer, 120 channels, intertrace of 12.5 m, shot interval 37.5 m (=circa 18.75 sec, ship speed 4 knots), record length 8 seconds. The data set was processed at OGS. The seismic trackline (and the segy stacked data) can be downloaded from the Antarctic Seismic Data Library System. The stacked seismic data are available after 4 years from the campaign. Keywords: Southern Ocean, Multichanenl Seismic, COLLAPS, Laura Bassi, Antarctica, SDLS.

  • 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

  • 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

  • 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

  • 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 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.

  • 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.

  • 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.

  • 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

  • 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