This week the mapping team will be conducting ground-truth surveys. Such surveys will take two forms: benthic grab samples and SPI imagery. Grabs are exactly what they sound like – we deploy a jaw-like instrument that collects (aka, grabs) samples of the seafloor, which we then analyze for sediment grain size and the biology that is present. SPI, or Sediment Profile Imagery, are photographs that capture the sediment-water interface (more on this later). The goal of ground-truthing is to verify our interpretations of the acoustic sidescan imagery and to provide fine-scale, highly detailed data to compliment the acoustic imagery.
Pontoon boat all set up for ground-truthing! The SPI camera and grab sampler are on board and ready to be used.