PIV measurements of near-bottom velocity and turbulence at the Bush Hill cold seep site (GC185, Gulf of Mexico)

This dataset contains near-bottom flow-velocity and turbulence measurements acquired with a particle image velocimetry (PIV) system at the Bush Hill cold seep site (Green Canyon block 185, GC185; northern Gulf of Mexico; ~540 m water depth). The PIV system imaged a vertical plane approximately 1 m above the seafloor at an active hydrocarbon seep vent. The instrument was deployed during R/V Roger Revelle cruise RR2405 and recovered during cruise RR2415, yielding a ~6-week record from 26 May to 8 July 2024. Velocity fields (41 × 51 vectors, 2.336 mm spacing, ~93 × 117 mm field of view) were acquired in ~10-minute bursts repeated every ~4 hours (six bursts per day; 249 bursts total), sampled at ~4 Hz within each burst. Gas-bubble image regions were masked during processing, so the velocities represent water motion; the two measured components are the in-plane horizontal (u) and vertical (v) velocities. This first release provides curated, derived flow products: (1) field-of-view–averaged horizontal and vertical velocity and their spatial fluctuation magnitude for every frame (~4 Hz time series), (2) burst-averaged velocity and fluctuation, and (3) burst-mean vertical profiles of velocity. Full turbulence statistics are under QA/QC and will be release in future updates.