Version 2025.0.00 |
9.0 Physical Seabed Samples
In general, sampling the surface sediment layer is usually adequate to define the bottom characteristics for charting. Clamshell bottom snappers or similar physical seabed samplers should be used to obtain as large a sample as possible.
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Data acquired during survey operations that differentiates varying seafloor characteristics (e.g. multibeam echo sounding backscatter data). -
Areas of potential vessel anchoring, i.e. samples must not be taken in depths greater than 80 meters or within dredged channels (DRGARE), pipeline and cable areas (PIPSOL, CBLARE), or fairways and approaches to a channel (FAIRWY).
The hydrographer must record the position of each sample obtained. In addition, each sample must be described and attributed in the Feature File. Refer to the Feature Attribute Encoding Guide for more details on physical seabed sample encoding.