OIL AND GAS FIELDS

Within this area covered by larger scale charts, certain fixed structures,
pipelines and cables have been omitted due to their complexity and frequent
change. The appropriate larger scale charts should be used in this area.
Production platforms and associated structures, including tanker moorings,
storage tankers and platforms on pipelines, generally exhibit Mo(U) lights,
aircraft obstruction lights and audible fog signals. Unauthorised navigation
is prohibited within 500 metres of all such structures.