http://bolin.su.se/data/oden-sas-2021-subbottom-1 Julia Muchowski, Carlos Castro, Caroline Bringensparr, Alexandra Padilla, Serdar Sakinan, Pauline Snoeijs Leijonmalm, Christian Stranne, Martin Jakobsson Bolin Centre Database 2024 Datafile Marine Sub-bottom profiles Marine geology Chirp Seismoacoustic Sub-bottom profiling Arctic Ocean SAS 2021 expedition Icebreaker Oden Earth science > Oceans > Bathymetry/seafloor topography Martin Jakobsson 2024-05-16T07:01:08+00:00 English 1 ##### File types Sub-bottom profile data are provided in two data formats; in original Kongsberg raw format (`.raw`) and in SEGY format (`.seg`), which is obtained after conversion from the original format using the Kongsberg Topas software. The SEGY files include navigation data (lat, lon in arcseconds). ##### Dataset structure Data files are provided in one `zip` file with two main folders named `raw` and `seg`. These folders are further structured in subfolders for each day. File names include day and time when data were collected. Because of the large data volume (42 GiB compressed; 48 GiB, 785 files uncompressed), downloading can take can take long time and requires sufficent disk space on your system. ##### Notes - Some files were originally given illogical names by the measurement system. This occurs in `raw` and `seg` subfolders named `20210914` and `20210916`. The original file names are left unchanged. - Some files are placed in subfolders with names that correspond to a date one or a few days before the date indicated by the file name. This occurs in several `raw` and `seg` subfolders. The data were collected in summer 2021 from Swedish icebreaker Oden during the Synoptic Arctic Survey (SAS) 2021 expedition organized by the [Swedish Polar Research Secretariat](https://www.polar.se/en/expeditions/previous-expeditions/arctic/synoptic-arctic-survey-2021/). Sub-bottom data were acquired using the [Kongsberg SBP 120 Sub-Bottom Profiler](https://www.kongsberg.com/globalassets/maritime/km-products/product-documents/sbp-120-sub-bottom-profiler) (2⁠ – ⁠7 kHz; 3° × 3°) chirp sonar installed onboard icebreaker Oden: - Pulse: 2.5⁠ – ⁠7 kHz chirp - Navigation data: GPS from Seatex Seapath 330 (data included in SEGY files) - Depth reference: Depth underneath transducer located 8 m below sea level. The measurement equipment was running throughout the expedition. Thus, data were collected along the ship track but there are some gaps at the beginning of the expedition.