RV Investigator Voyage IN2025_V05 SBP29 Sub-bottom Profiler Data

This record describes sub bottom profiler data collected on RV Investigator voyage IN2025_V05, 'Eruption, destruction and seafloor ecosystem recovery – Tonga 2022 eruption of the century', which departed Hobart on 10 Aug and ended in Brisbane on 01 Oct 2025 (local). The voyage’s first leg transited from Hobart to Nuku’alofa (10–19 Aug 2025), where science participants boarded. A mid-voyage transfer occurred on 05 Sep, and all science personnel disembarked in Nuku’alofa on 23 Sep before the final transit to Brisbane (23 Sep–1 Oct 2025).The Kongsberg SBP29 (sub bottom profiler) was used to acquire data containing the specular reflections at different sediment interfaces below the seafloor. The SBP120 provides a 3° by 3° angular resolution.The echosounder's frequency sweep range is from 2.5 to 9 kHz. The SBP29 was logged continuously for the extent of the voyage.Data are stored in *.raw (2002 files 22 GB) raw and *.seg (1991 files 21.9 GB) segy formats at CSIRO.The segy format data had a real time processing stream applied, which applies gain, a gain correction, matched filter with replica shaping, an attribute calculation for instantaneous amplitude and time variable gain.Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request