plate-forme off-shore

CONT: Les ingénieurs de structure se rendent compte de l'intérêt économique des bétons à hautes performances [...] dans des domaines de plus en plus nombreux : immeubles de grande hauteur, ponts, plates-formes off-shore [...]
OBS: Pluriel : des plateformes, des plates-formes.
OBS: plateforme (sing.); plateformes (pl.) : Ces graphies, puisées des Rectifications de l'orthographe recommandées par le Conseil supérieur de la langue française, sont attestées dans le Petit Robert (2004).

OBS: jacket: A support that is firmly secured to the ocean floor and to which the legs of a platform are anchored.
OBS: The design of a jacket, i.e. a lifted, launched or self-floating jacket, is determined primarily by the offshore installation equipment available and the intended water depth. In general the preference is to lift the jacket in place. The size of such jackets has [been] increasing as offshore lifting capacity has grown. With modern lifting capacity now up to 14,000 tonnes, jackets approaching this order of magnitude are now candidates for lifting into position.