Sediment echosounder processed data (Atlas Parasound P70 echosounder working area dataset, ASD format converted to SEG-Y format) of RV SONNE during cruise SO304, Bengal Fan, Indian Ocean

During the SO304 cruise (22 February – 07 April 2024), sub‑bottom profiles were collected on the Bengal Fan (Bay of Bengal) with the hull‑mounted Teledyne Reson PARASOUND P70 echosounder on RV SONNE. The archived profiles target a lobe complex on the Bengal Fan. The PARASOUND system generates a secondary low‑frequency signal (SLF; 0.5–6 kHz) by non‑linear interaction of two primary high‑frequency signals (PHF; adjustable between 18.5 and 33 kHz), producing a transmission beam of 4.5° along‑track × 5° across‑track. Consequently, the lateral resolution corresponds to approximately 7.9 % of water depth along‑track and 8.7 % across‑track. Throughout the cruise a 4 kHz SLF with a ≈ 0.25 ms non‑rectangular pulse was used as the standard setting, yielding decimetre‑scale vertical resolution. The profiler operated in quasi‑equidistant mode, transmitting pulses at regular intervals regardless of whether the previously transmitted signal had already been received, thereby maximising horizontal coverage. For the working‑area dataset the ping rate was about 1 s, giving 3–4 m shot‑point spacing for profiles GeoB24‑013, 031, 032 and 045 (≈ 5 kn ship speed) and 6–7 m spacing for profiles P089, P110, P111, and P185 (8–10 kn speed). System depth and ping rates were adjusted using depth information from the EM122 echo‑sounder or from the PHF signal. The carrier signal including the signal phase information has been stored. Raw PHF and SLF data were stored in the native PARASOUND ASD format and also converted to PS3 and SEG‑Y formats. Because occasional gaps appeared in the PS3/SEG‑Y files, the SLF data were replayed on a second acquisition computer with the ATLAS PARASTORE software and re‑exported as gap‑free SEG‑Y files. The dataset provides continuous sub‑bottom profiles of the upper ~100 m of sedimentary layers, enabling structural imaging, identification of suitable coring locations, and imaging of acoustic backscatter from organisms or suspended material in the water column. Coordinates in the SEG-Y files are given in WGS84/UTM45N.

Identifier
DOI https://doi.pangaea.de/10.1594/PANGAEA.995404
PID https://hdl.handle.net/10013/epic.36387
Related Identifier References https://hdl.handle.net/10013/epic.cfe66162-64d9-4cfd-a209-eb591954b5c5
Related Identifier References https://doi.org/10.48433/cr_so304
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.995404
Provenance
Creator Schwenk, Tilmann ORCID logo; Römer-Stange, Nikolas ORCID logo; Feddersen, Greta; Bernhard, Renée; Athanassiadis, Emilia; Spieß, Volkhard
Publisher PANGAEA
Publication Year 2026
Funding Reference Federal Ministry of Education and Research https://doi.org/10.13039/501100002347 Crossref Funder ID 03G0304A https://foerderportal.bund.de/foekat/jsp/SucheAction.do?actionMode=view&fkz=03G0304A SO304 - BENGAL SHELF: Der Bengal Schelf als kritische Grenzfläche zwischen Land-Ozean-Atmosphäre und Archiv
Rights Creative Commons Attribution 4.0 International; Data access is restricted (moratorium, sensitive data, license constraints); https://creativecommons.org/licenses/by/4.0/
OpenAccess false
Representation
Resource Type Dataset
Format text/tab-separated-values
Size 16 data points
Discipline Earth System Research
Spatial Coverage (85.232W, 7.253S, 85.237E, 7.261N)
Temporal Coverage Begin 2024-02-24T06:41:32Z
Temporal Coverage End 2024-04-05T10:43:00Z