2025_programme: Sparker as a remarkable alternative to air-guns in deep-water sedimentary systems imagery

• Day: June 19, Thursday
    Location / Time: TBA at 15:30 - 16:30
• Last minutes changes: -
• Session: Poster session
  Organiser(s): N/A
  Chairperson(s): N/A
• Lecture: Sparker as a remarkable alternative to air-guns in deep-water sedimentary systems imagery
  Paper ID: 2190
  Author(s): Davide Oregioni, Laure Schenini, Julien Bailleul, Jean-Xavier Dessa
  Presenter: Davide Oregioni
  Abstract: Sparker acoustic sources are widely used in marine seismic exploration to provide high-resolution vertical imagery. Sparkers are relatively simple, inexpensive and a one-man-operation device. These sources are mainly operated at shallow water depths, from few tens of meters up to 1000 m. The energy stored in their high-voltage capacitors is discharged rapidly through a sparker-electrode generating a high-frequency signal ranging from 100 to 3000 Hz (depending on energy delivered and electrode characteristics). In this study we show exceptional results with 5-10 m of resolution obtained for 300-350 m of penetration down to around 2200m of water depth. The acoustic source deployed in this study is a 2 kJ sparker source, coupled with a fish-bone planar multi-tip electrode optimized for a wide range of energies (160 to 3000 joules). Acoustic waves were picked-up by a 24 channels analog streamer with a group spacing of 12.5m and a hydro spacing of 0.5m. A complete processing workflow was designed and applied to the data to provide very high resolution migrated images. The study area shows very specific morpho-sedimentary features, also visible in the bathymetry. Located at the junction between the emerged Calabrian arc and the offshore Ionian subduction wedge, the area is rich of canyons incising the slope, fields of sediment waves at the bottom of the slope and shows a complex interplay between gravity-driven systems and the development of intra-slope basins controlled by the deformation. Because of the high-quality data recorded during this study, and the growing trend of countries banning the use of air-guns, we can enthusiastically affirm that sparker sources can be considered as an excellent alternative to pneumatic sources, i.e. air-guns, up to 2000 m water-depth and at these structural levels of investigation.
• Corresponding author: Mr Davide Oregioni
  Affiliation: Université Côte d'Azur, CNRS, IRD, Observatoire de la Côte d'Azur, Géoazur
  Country: France