OIL AND GAS FIELDS Within this area, certain fixed structures, pipelines and cables have been omitted due to their complexity and frequent change. 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. In addition and in accordance with Saudi Seaports Authority Notices to Mariners the majority of such features have been omitted in oilfield areas within the Saudi Arabian EEZ.