Abstract: An improved facility, for the drilling and production of hydrocarbon deposits located in a deep sea bed, includes a central structural column having a bottom end secured to a submarine base mounted on the sea bed and a top end secured to a subsea buoy. A plurality of peripheral tubular conduits are located around the central structural column and connected thereto by a guide device which permits the peripheral tubular amendments to move relative thereto and positions the peripheral tubular conduits in parallel with the central structural column.

Abstract: An offshore drilling installation comprising an underwater base spaced from an underwater buoy and in communication therewith by a connecting conduit. The underwater buoy represents the upward extension of the sea bed which serves to support an above-sea platform. The underwater buoy is further secured to the sea bed by mooring lines. Oil containing means is provided in the underwater base.

Abstract: A semi-submersible floating apparatus for operating at sea and a method of assembling the same are disclosed. The apparatus comprises two or more submerged or bottom hulls supporting, by pillars, one or more working platforms or top hulls all of which are elongate floating bodies adapted to be individually constructed. The top hull is arranged transversely of the bottom hulls and is affixed by lateral connections adjacent the tops of the pillars. In assembling the apparatus, the bottom hulls are interconnected and fitted with the pillars and then ballasted until the bottom hulls are submerged. The top hull is floated until centered transversely of the bottom hulls and raised to a position for the lateral connection thereof. Alternately, the top hull is connected to the pillars and the bottom hulls are deballasted to raise the top hull above the level of the sea.