Hydrographic survey

Hydrographic survey in its strictest sense is the process of gathering information about navigable waters for the purposes of safe navigation of vessels. It strictly applies to survey of any navigable waters, including lakes and rivers, but it is most commonly applied to marine navigation. The term may be more broadly used for a wide variety of data gathering exercises for the purpose of describing the seafloor for a variety of purposes. The largest hydrographic community globally is involved in the description of offshore oilfields from their initial design phase through to regular inspections of the infrastructure of a mature sub sea oil infrastructure. This may be commonly referred to as Offshore Survey
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Survey of water area, with particular reference to submarine relief, and any adjacent land. See: oceanographic survey