The hydrographic and geo-physical instrumentation allow the INFOMAR team to make accurate predictions as to the type of material present on the seabed e.g. rocks, pebbles, sand, mud. In order to confirm these predictions are correct we take representative sediment samples from each survey area. This process is called ground-truthing or sampling.
Grab sampling is the most popular method of ground-truthing. There are three main types of grab used depending on the size of the vessel and the weather conditions; Day Grab, Shipek or Van Veen Grabs. The grabs acquire a sample of sediment from the surface layer to be stored for later analysis in order to cross-reference the seabed type classifications that are made from the MBES bathymetry and backscatter datasets. This leads to the creation of sediment classification maps. The Geo Resources ‘Vibrocore’ takes sediment sample cores via a metal tube penetrating the sediment. The core samples provide data on historical climate records and sediment deposition in each area.
Further information on the INFOMAR sampling strategy is available via the blue button, from our interactive sediment map or from the Data page.